U.S. patent application number 17/155392 was filed with the patent office on 2021-08-05 for arm prosthetic device.
The applicant listed for this patent is DEKA Products Limited Partnership. Invention is credited to David Blumberg, JR., Stewart M. Coulter, Thomas A. Doyon, Christopher O. Evans, N. Christopher Perry, Dirk A. van der Merwe, Keith D. Violette.
Application Number | 20210236306 17/155392 |
Document ID | / |
Family ID | 1000005534783 |
Filed Date | 2021-08-05 |
United States Patent
Application |
20210236306 |
Kind Code |
A1 |
Evans; Christopher O. ; et
al. |
August 5, 2021 |
ARM PROSTHETIC DEVICE
Abstract
A prosthetic arm apparatus including a plurality of segments
that provide a user of the prosthetic arm apparatus with
substantially the same movement capability and function as a human
arm. The segments are connectable to one another and connectable to
a prosthetic support apparatus that may be adorned by the user.
Some segments may provide movement about more than one axis using a
single actuator. The prosthetic arm apparatus may include a user
interface incorporated therein and may include one or more
communication systems for communicating with external devices.
Inventors: |
Evans; Christopher O.;
(Amherst, NH) ; Perry; N. Christopher;
(Manchester, NH) ; van der Merwe; Dirk A.;
(Canterbury, NH) ; Violette; Keith D.; (Sandown,
NH) ; Coulter; Stewart M.; (Bedford, NH) ;
Doyon; Thomas A.; (Manchester, NH) ; Blumberg, JR.;
David; (Deerfield, NH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DEKA Products Limited Partnership |
Manchester |
NH |
US |
|
|
Family ID: |
1000005534783 |
Appl. No.: |
17/155392 |
Filed: |
January 22, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15675990 |
Aug 14, 2017 |
10918500 |
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17155392 |
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|
14658840 |
Mar 16, 2015 |
9730813 |
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15675990 |
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|
13088063 |
Apr 15, 2011 |
8979943 |
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14658840 |
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|
12706609 |
Feb 16, 2010 |
8449624 |
|
|
13088063 |
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12027141 |
Feb 6, 2008 |
9114028 |
|
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12706609 |
|
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61382665 |
Sep 14, 2010 |
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61168786 |
Apr 13, 2009 |
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60899833 |
Feb 6, 2007 |
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60963639 |
Aug 6, 2007 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2002/7665 20130101;
A61F 2002/5083 20130101; A61F 2002/7635 20130101; A61F 2/78
20130101; A61F 2002/587 20130101; A61F 2002/701 20130101; A61F
2002/5061 20130101; A61F 2002/764 20130101; A61F 2002/6845
20130101; A61F 2002/5001 20130101; A61F 2002/6881 20130101; A61F
2/585 20130101; A61F 2002/704 20130101; A61F 2250/008 20130101;
A61F 2/74 20210801; A61F 2/68 20130101; B25J 18/00 20130101; A61F
2002/6836 20130101; A61F 2/70 20130101; A61F 2/581 20130101; A61F
2220/0075 20130101; A61F 2/54 20130101; A61F 2250/0074 20130101;
F16D 41/105 20130101; A61F 2002/30462 20130101; B25J 15/0009
20130101; A61F 2/582 20130101; A61F 2002/7625 20130101; A61F 2/586
20130101; A61F 2002/7862 20130101; A61F 2002/769 20130101; A61F
2002/705 20130101; A61F 2002/7645 20130101; F16D 41/12
20130101 |
International
Class: |
A61F 2/54 20060101
A61F002/54; A61F 2/58 20060101 A61F002/58; B25J 15/00 20060101
B25J015/00; B25J 18/00 20060101 B25J018/00; A61F 2/70 20060101
A61F002/70; A61F 2/68 20060101 A61F002/68 |
Goverment Interests
STATEMENT OF GOVERNMENT INTEREST
[0002] This invention was made with Government support under
Contract Number W911NF-09-C-0035 awarded by the U. S. Army RDECOM
ACQ CTR. The Government has certain rights in the invention.
Claims
1. A compound motion assembly comprising: an input member; and an
output member moveably coupled to the input member; wherein
actuation of the compound motion assembly generates movement of the
output member relative to the input member along a compound motion
path having motion about at least two axes.
2. The compound motion assembly according to claim 1, additionally
comprising a drive arrangement for controlling movement of the
output member relative to the input member.
3. The compound motion assembly according to claim 2, wherein the
rate of motion about each axis varies as the drive arrangement is
actuated at a constant rate.
4. A compound motion assembly providing a two-axis compound motion
through a pre-determined path, the compound motion assembly
comprising: an input member; an output member moveably coupled to
the input member through at least a first joint having a first axis
and a second joint having a second axis, the first and second
joints being connected in series; a path member having a fixed path
profile formed therein, the path member fixedly coupled to the
input member; and a follower member coupled to the output member
and engaging the fixed path profile of the path member; wherein
actuation of the compound motion assembly generates pivotal
movement of the output member relative to the input member about
both the first axis and the second axis along the pre-determined
path.
5. The compound motion assembly according to claim 4, additionally
comprising a drive arrangement driving the compound motion assembly
through one of the first or second joints to cause movement of the
output member.
6. A safety mechanism for a prosthetic device having at least one
motorized drive and a controller for controlling actuation of the
motorized drive, the safety mechanism comprising; an actuator
electrically coupled in parallel with the controller between the
motorized drive and a power source; wherein actuation of the
actuator supplies power to the motorized drive bypassing the
controller and actuates the motorized drive until it reaches a safe
position.
7. The safety mechanism according to claim 6, wherein the actuator
includes at least two switches that are coupled to actuate
simultaneously and electrically coupled in parallel; and wherein
actuation of only one switch of the at least two switches is
sufficient to actuate the motorize drive, thereby providing
redundancy.
8. The safety mechanism according to claim 6, the actuator is
electrically coupled in parallel with the controller between the
power source and a plurality of motorized drives.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/675,990, filed Aug. 14, 2017, which is a
continuation of U.S. patent application Ser. No. 14/658,840, filed
Mar. 16, 2015, which is a continuation of U.S. patent application
Ser. No. 13/088,063, filed Apr. 15, 2011, which claims priority to
U.S. Provisional Patent Application No. 61/382,665, filed Sep. 14,
2010, and is a continuation-in-part of U.S. patent application Ser.
No. 12/706,609, filed Feb. 16, 2010, which claims priority to U.S.
Provisional Patent Application Ser. No. 61/168,786, filed Apr. 13,
2009, and is a continuation-in-part of U.S. patent application Ser.
No. 12/027,141, filed Feb. 6, 2008, which claims priority to U.S.
Provisional Patent Application Ser. No. 60/899,833, filed Feb. 6,
2007, and U.S. Provisional Patent Application Ser. No. 60/963,639,
filed Aug. 6, 2007, each of which is hereby incorporated by
reference in its entirety.
TECHNICAL FIELD
[0003] The present development relates to mechanical and medical
devices and, more particularly, to prosthetic devices. More
particularly, the development utilizes mechanical structure and
user or motor stimuli to operate a prosthesis similarly to a human
limb.
BACKGROUND INFORMATION
[0004] Existing prosthetic arms have limited movement for the user.
Further, there are limited options for those patients who have lost
their entire arm, shoulder to hand. Also, hand portions of existing
prosthetic arms give the user, in many instances, one degree of
movement. These known prosthetic devices provide limited capability
with respect to, amongst other things, finer tasks.
[0005] Accordingly, there is a need for a prosthetic arm that
replaces an arm from shoulder to hand and that has increased
degrees of freedom. There is also a need for a prosthetic hand that
moves in a realistic manner.
SUMMARY
[0006] It is one aspect of the present device to provide a
prosthetic device that will allow the user improved range of
motion, improved tactile capabilities, increased comfort for the
user, and decreased reliance on manual positioning of the
prosthesis.
[0007] According to some aspects of the present invention, a
compound motion assembly for providing a two-axis compound motion
through a pre-determined path includes an input member and an
output member moveably coupled to the input member. Actuation of
the compound motion assembly generates movement of the output
member relative to the input member along a compound motion path
having motion about at least two axes. In some embodiments, the
compound motion assembly includes a drive arrangement for
controlling movement of the output member relative to the input
member. In these embodiments, the rate of motion about each axis
may vary as the drive arrangement is actuated at a constant
rate.
[0008] According to some embodiments, the output member may be
moveably coupled to the input member through at least a first joint
having a first axis and a second joint having a second axis, the
first and second joints being connected in series. The compound
motion assembly may include a path member that is fixedly coupled
to the input member and has a fixed path profile formed therein
defining the compound motion path. A follower member may be coupled
to the output member and engaging the fixed path profile of the
path member such that pivotal movement of the output member
relative to the input member about both the first axis and the
second axis is generated as the follower member moves along the
pre-determined path. In some embodiments, the drive arrangement may
drive the compound motion assembly through one of the first or
second joints to cause movement of the output member.
[0009] According to some aspects of the present invention, a
prosthetic limb segment has a housing with an input interface and
an output interface that are moveable with respect to one another
and a motorized drive for effecting movement of at least one of the
output interface or the input interface. The prosthetic limb
segment also includes a controller disposed within the housing for
controlling the motorized drive and also for communicating with and
controlling at least a second motorized drive of at least a second
prosthetic limb segment.
[0010] According to some embodiments, the prosthetic limb segment
may include a user interface integrally formed in the housing and
in communication with the controller. The user interface may
include a status indicator for displaying information from the
controller. In some embodiments, the status indicator may have one
or more LEDs for displaying information from the controller. In
some embodiments, at least a portion of the LEDs are arranged in an
array. In some embodiments, the user interface includes at least
one input member for providing a signal to the controller. The user
interface may include a protective cover, which may be flexible and
may include at least a portion that is translucent to allow light
from an LED disposed beneath the protective cover there
through.
[0011] According to some aspects of the present invention, a safety
mechanism for a prosthetic device having at least one motorized
drive and a controller for controlling the motorized drive is
provided. The safety mechanism includes an actuator electrically
coupled in parallel with the controller between the motorized drive
and a power source so that actuation of the actuator supplies power
to the motorized drive bypassing the controller and actuates the
motorized drive until it reaches a safe position.
[0012] According to some embodiments, the safety mechanism may
include an actuator that has at least two switches coupled to
actuate simultaneously and electrically coupled in parallel so that
actuation of only one switch of the at least two switches is
sufficient to actuate the motorize drive, thereby providing
redundancy. In some embodiments, the actuator is electrically
coupled in parallel with the controller between the power source
and a plurality of motorized drives such that actuation of the
actuator supplies power to the plurality of motorized drives and
actuates each motorized drive until it reaches a safe position.
[0013] These aspects of the invention are not meant to be exclusive
and other features, aspects, and advantages of the present
invention will be readily apparent to those of ordinary skill in
the art when read in conjunction with the appended claims and
accompanying drawings.
[0014] The same compliance method is applied to the MRP drive,
allowing it to store elastic energy.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] These and other features and advantages of the present
invention will be better understood by reading the following
detailed description, taken together with the drawings wherein:
[0016] FIG. 1 is a perspective view of one embodiment of a
prosthetic arm apparatus according to the present invention;
[0017] FIG. 2 is an exploded view of the prosthetic arm apparatus
of FIG. 1;
[0018] FIG. 3 is a rear view of a shoulder abductor of the
prosthetic arm apparatus of FIG. 1 according to the present
invention;
[0019] FIG. 4 is a front view of the shoulder abductor of FIG.
3;
[0020] FIG. 5 is a side view of the shoulder abductor of FIG.
3;
[0021] FIG. 6 is a perspective view of the shoulder abductor of
FIG. 3;
[0022] FIG. 7 is an exploded perspective view of the shoulder
abductor of FIG. 6;
[0023] FIG. 8 is a perspective view of a shoulder flexion assembly
of the prosthetic arm apparatus of FIG. 1 according to the present
invention;
[0024] FIG. 9 is a reverse perspective view of the shoulder flexion
assembly of FIG. 8;
[0025] FIG. 10 is an exploded perspective view of the shoulder
flexion assembly of FIG. 8;
[0026] FIG. 11 is a cross-sectional perspective view of the
shoulder flexion assembly of FIG. 8;
[0027] FIG. 12 is a top view of a non-backdriving clutch according
to the present invention;
[0028] FIG. 13 is a perspective view of a fully assembled
compliance subassembly of the shoulder flexion assembly of FIG.
8;
[0029] FIG. 14 is a perspective view of the bottom portion of the
compliance subassembly of FIG. 13;
[0030] FIG. 15 is a perspective view of the top portion of the
compliance subassembly of FIG. 13;
[0031] FIG. 16 is a perspective view of a humeral rotator of the
prosthetic arm apparatus of FIG. 1 according to the present
invention;
[0032] FIG. 17 is a cross-sectional perspective view of the humeral
rotator of FIG. 16;
[0033] FIG. 18 is a perspective view of an elbow flexion assembly
of the prosthetic arm apparatus of FIG. 1 according to the present
invention;
[0034] FIG. 19 is a cross-sectional perspective view of one
embodiment of the elbow flexion 15 assembly shown without the
radial mount;
[0035] FIG. 20 is a cross-sectional perspective view of the elbow
flexion assembly shown with the radial mount;
[0036] FIG. 21A is a perspective view showing the compliance
subassembly of the elbow flexion assembly of FIG. 19;
[0037] FIG. 21B is an exploded perspective view of a compliance
subassembly according to another embodiment of the present
invention;
[0038] FIG. 22 is an exploded perspective view of the elbow flexion
assembly of FIG. 18;
[0039] FIG. 23 is a perspective view of a wrist rotator of the
prosthetic arm apparatus of FIG. 1 according to the present
invention;
[0040] FIG. 24 is a cross-sectional perspective view of the wrist
rotator of FIG. 23;
[0041] FIG. 25 is a perspective view of a wrist flexion assembly
and a hand control module of the prosthetic arm apparatus of FIG. 1
according to the present invention;
[0042] FIG. 26 is a rear perspective view of the wrist flexion
assembly and hand control module of FIG. 25;
[0043] FIG. 27 is a cross-sectional perspective view of the wrist
flexion assembly and hand control module of FIG. 25;
[0044] FIG. 28 is a perspective view of a wrist assembly output arm
of FIG. 25;
[0045] FIG. 29 is a side view of a hand assembly of the prosthetic
arm apparatus of FIG. 1 according to one embodiment;
[0046] FIG. 30 is a front view of one embodiment of the hand
assembly of FIG. 29;
[0047] FIG. 31 is a perspective view of one embodiment of the hand
assembly of FIG. 29 showing an index finger tensioner assembly;
[0048] FIG. 32 is a cross-sectional view of one embodiment of the
hand assembly of FIG. 29 showing an MRP tensioner assembly;
[0049] FIG. 33 is a front cross-sectional view of one embodiment of
the MRP differential drive of FIG. 30;
[0050] FIG. 34 is a front cross-sectional view of one embodiment of
thumb differential drives of FIG. 30;
[0051] FIG. 35 is a side view of one embodiment of the hand
assembly of FIG. 30 showing a tactile feedback sensor according to
the present invention;
[0052] FIG. 36 is a perspective view of one embodiment of the
tactile feedback sensor and a feedback actuator of the prosthetic
arm apparatus of FIG. 1;
[0053] FIG. 37 is a perspective view of another embodiment of the
tactile feedback sensor and feedback actuator of the prosthetic arm
apparatus of FIG. 1 according to the present invention;
[0054] FIG. 38 is an exploded view of a portion of the hand showing
another embodiment of the index and MRP fingers drives;
[0055] FIG. 39 is an exploded view of another embodiment of the
hand;
[0056] FIG. 40 is a perspective view of another embodiment of the
hand;
[0057] FIG. 41 is a perspective cutaway view of the hand;
[0058] FIG. 42A shows an embodiment of an integrated shoulder unit
according to an embodiment of the present invention;
[0059] FIG. 42B is a partial cutaway view of the integrated
shoulder unit of FIG. 42A in an inactuated state;
[0060] FIG. 42C is a partial cutaway view of the integrated
shoulder unit of FIG. 42A in an actuated state;
[0061] FIG. 43 is a cross sectional view of another embodiment of
an integrated shoulder unit according to the present invention;
[0062] FIG. 44 is a cross sectional view of another embodiment of
the integrated shoulder unit of FIG. 43;
[0063] FIG. 45 is a top view of a shoulder abductor and shoulder
flexion assembly according to another embodiment of the present
invention;
[0064] FIG. 46 is a side plane view of shoulder flexion assembly
mount of the shoulder abductor of FIG. 45;
[0065] FIG. 47A is a side cross-sectional view of an embodiment of
a shoulder free swing system according to the present
invention;
[0066] FIG. 47B is a front cross-sectional view of the shoulder
free swing system of FIG. 47A when disengaged;
[0067] FIG. 47C is a front cross-sectional view of the shoulder
free swing system of FIG. 47C when engaged;
[0068] FIG. 48A is a side perspective view of a shoulder free swing
system according to another embodiment of the present
invention;
[0069] FIG. 48B is a side cross-sectional view of the shoulder free
swing system of FIG. 48A;
[0070] FIG. 49 is a cross-sectional view of one embodiment of a
rotator according to the present invention;
[0071] FIG. 50 is a side view of one embodiment of a flexion
assembly according to the present invention;
[0072] FIG. 51 is a front view of the flexion assembly of FIG.
50;
[0073] FIG. 52 is a perspective view of another embodiment of a
wrist flexion assembly according to the present invention;
[0074] FIG. 53 is a partially exploded perspective view of the
wrist flexion assembly of FIG. 52;
[0075] FIG. 54 is a top cross-sectional view of the wrist flexion
assembly of FIG. 52;
[0076] FIG. 55 is a top cross-sectional view of the wrist flexion
assembly of FIG. 52;
[0077] FIG. 56 is a cross-sectional view of another embodiment of a
wrist flexion assembly according to the present invention;
[0078] FIG. 57A is a partial cross-sectional view of another
embodiment of the non-backdriving dutch of FIG. 12;
[0079] FIG. 57B is a cross-sectional view of another embodiment of
the non-backdriving dutch of FIG. 12;
[0080] FIG. 57C is a cross-sectional view of a combination gearbox
including the non-backdriving dutch of FIG. 57B;
[0081] FIG. 58A is an exploded perspective view of an embodiment of
the hand assembly according to the present invention;
[0082] FIG. 58B is an exploded perspective view of an embodiment of
an index finger structure of FIG. 58A;
[0083] FIG. 59 is a perspective view of a compliance assembly
according to an embodiment of the present invention;
[0084] FIG. 60A is a side view of a breakaway mechanism according
to an embodiment of the present invention;
[0085] FIG. 60B is a front cross-sectional view of the breakaway
mechanism of FIG. 60A;
[0086] FIG. 61A-63B are various views of another embodiment of a
breakaway mechanism according to the present invention;
[0087] FIG. 64 is a front view of a magnetic sensor according to
some embodiments of the present invention;
[0088] FIG. 65 is a side cross-sectional view of another embodiment
of a magnetic sensor according to the present invention;
[0089] FIG. 66 is a cross-sectional view of a hand assembly
according to an embodiment of the present invention;
[0090] FIG. 67 is a front view of a hand assembly cosmesis
according to an embodiment of the present invention;
[0091] FIG. 68A is a front view of an embodiment of the cosmesis of
FIG. 67 with removable finger portions;
[0092] FIG. 68B is a cross-sectional view of an embodiment of a
finger structure cosmesis of FIG. 68A;
[0093] FIG. 69 is a perspective view of another embodiment of the
cosmesis of FIG. 67;
[0094] FIG. 70 is a side perspective view of another embodiment of
a cosmesis according to the present invention;
[0095] FIG. 71 is a perspective view of a prosthetic arm apparatus
having a temperature sensor according to an embodiment of the
present invention;
[0096] FIG. 72A is a side view of a thumb structure according to an
embodiment of the present invention;
[0097] FIG. 72B is a side cross-sectional view of the thumb
structure of FIG. 72A;
[0098] FIG. 72C is a side cross-sectional view of the thumb
structure of FIG. 72A under a load;
[0099] FIG. 73 is a side cross-sectional view of a thumb structure
according to another embodiment of the present invention;
[0100] FIG. 74 is a top view of a humeral rotator and an elbow
flexion assembly according to another embodiment of the present
invention;
[0101] FIG. 75A is a perspective view of a prosthetic arm apparatus
having safety features according to an embodiment of the present
invention;
[0102] FIG. 75B is a perspective view of a prosthetic arm apparatus
having safety features according to an embodiment of the present
invention;
[0103] FIG. 75C is a perspective view of the wrist rotator
according to an embodiment of the present invention;
[0104] FIG. 75D is a side perspective view of the wrist rotator and
a transradial mount according to an embodiment of the present
invention;
[0105] FIG. 75E is a front perspective view of the wrist rotator
and a transradial mount of FIG. 75D;
[0106] FIG. 76 is a perspective view of a wrist flexion assembly
according to another embodiment of the present invention;
[0107] FIG. 77 is a perspective view of a first cam bearing of the
wrist flexion assembly of FIG. 76;
[0108] FIG. 78 is a perspective view of a second cam bearing of the
wrist flexion assembly of FIG. 76;
[0109] FIG. 79A is a perspective view of the wrist flexion assembly
of FIG. 76 in a first position;
[0110] FIG. 79B is a perspective view of the wrist flexion assembly
of FIG. 76 in a second position;
[0111] FIG. 79C is a perspective view of the wrist flexion assembly
of FIG. 76 in a third position;
[0112] FIG. 80 is a line graph of a fixed movement path of the
wrist flexion assembly of FIG. 76;
[0113] FIG. 81 is a side perspective view of a compound motion
assembly according to an embodiment of the present invention;
[0114] FIG. 82 is a top perspective view of an embodiment of a
fixed path member of the compound motion assembly of FIG. 81;
[0115] FIG. 83 is a top view of the fixed path member of FIG.
82;
[0116] FIG. 84 is a side view of the compound motion assembly of
FIG. 81;
[0117] FIG. 85 is a cross sectional view of the compound motion
assembly of FIG. 84;
[0118] FIG. 86 is an exploded perspective view of the compound
motion assembly of FIG. 84;
[0119] FIG. 87 is a side perspective view of a compound motion
assembly of FIG. 81 having the hand assembly attached thereto;
[0120] FIGS. 88A-88F are side perspective views of the compound
motion assembly of FIG. 81 at various positions along its full
range of motion;
[0121] FIG. 89 is a line graph of a compound motion path of the
compound motion assembly of FIG. 81;
[0122] FIG. 90 is a side perspective view of an embodiment of an
antenna according to the present invention;
[0123] FIG. 91 is a partially exploded view of the antenna of FIG.
90;
[0124] FIG. 92 is a schematic view of the antenna matching network
of FIG. 90;
[0125] FIG. 93 is a top perspective view of an embodiment of
another antenna according to the present invention;
[0126] FIG. 94 is a schematic view of the antenna branching network
of FIG. 93;
[0127] FIG. 95 is a side perspective view of another embodiment of
a compound motion assembly according to the present invention;
and
[0128] FIG. 96 is a side perspective view of another embodiment of
a compound motion assembly according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0129] Referring to FIGS. 1 and 2, a prosthetic arm apparatus 10
for attachment to a shoulder of a shoulder disarticulated amputee
includes a plurality of segments, including a shoulder abductor 12,
a shoulder flexion assembly 14, a humeral rotator 16, an elbow
flexion assembly 18, a wrist rotator 20, a wrist flexion assembly
22, and a hand assembly 24. The prosthetic arm apparatus 10, in the
exemplary embodiment, has the dimensions and weight of a female arm
of a fiftieth percentile, so that many different users may
comfortably use the prosthetic arm apparatus 10. As should be
understood by those skilled in the art, the prosthetic arm
apparatus 10 may be constructed to larger or smaller dimensions if
desired. The prosthetic arm apparatus 10 may be controlled by a
control system (not shown), such as the various control systems
described in U.S. patent application Ser. No. 12/027,116, filed
Feb. 6, 2008, U.S. patent application Ser. No. 12/706,575, filed
Feb. 16, 2010, U.S. patent application Ser. No. 12/706,471, filed
Feb. 16, 2010, and the U.S. Patent Application entitled SYSTEM,
METHOD AND APPARATUS FOR CONTROL OF A PROSTHETIC DEVICE, filed on
the same day as the present application and assigned to the same
assignee, each of which is hereby incorporated by reference in its
entirety.
[0130] Referring to FIG. 3, one embodiment of the shoulder abductor
12 is shown. The shoulder abductor 12 includes a harness mount 26
for connecting the prosthetic arm apparatus 10, shown in FIG. 1, to
a support apparatus, as the various prosthetic supports described
in U.S. patent application Ser. No. 12/026,971, filed Feb. 6, 2008,
U.S. patent application Ser. No. 12/706,340, filed Feb. 16, 2010,
and the U.S. Patent Application entitled DYNAMIC SUPPORT APPARATUS
AND SYSTEM, filed on the same day as the present application and
assigned to the same assignee, each of which is hereby incorporated
by reference in its entirety. The harness mount 26 has harness
interface holes 28 that may be used to attach the abductor 12 to a
prosthetic harness (not shown) or other system for supporting the
prosthetic arm apparatus 10. In the exemplary embodiment, the
harness or prosthetic support apparatus may also be one disclosed
in co-pending U.S. patent application Ser. No. 12/026,971, by
Altobelli, et al., entitled Dynamic Support Apparatus filed on Feb.
6, 2008, which is hereby incorporated by reference in its
entirety.
[0131] Referring to FIG. 4, the shoulder abductor 12 also has a
shoulder flexion assembly mount 30, shown according to one
embodiment. The shoulder flexion assembly mount 30 interfaces with
the shoulder flexion assembly 14 to mount the shoulder flexion
assembly 14 onto the shoulder abductor 12. In one embodiment, the
flexion assembly mount 30 has interface holes 32 to facilitate
connection of the shoulder flexion assembly 14 by attachment means
such as bolts.
[0132] Referring to FIG. 5, the shoulder abductor 12 further
includes an abductor joint 34, shown according to one embodiment.
The abductor joint 34 is used to pivot the shoulder flexion
assembly mount 30 away from the harness mount 26 and back toward
the harness mount 26.
[0133] Referring to FIGS. 6 and 7, the shoulder abductor 12
includes an abductor motor 36 to control the pivotal movement of
the abductor joint 34, shown in FIG. 5, both the shoulder abductor
12 and abductor motor 36 shown according to one embodiment. In this
embodiment, the abductor motor 36 is a brushed DC motor controlling
the pivotal movement through an abductor belt 38 connected to a
worm drive 41 driving a worm wheel 39 connected to an abductor
harmonic drive gearing system 40.
[0134] Referring to FIGS. 8 and 9, the shoulder flexion assembly
14, in one embodiment, has a main shoulder housing 42, with an
abductor interface 44 for connecting the shoulder flexion assembly
14 to the shoulder abductor 12. The shoulder flexion assembly 14
also has a humeral interface 46 for connecting the humeral rotator
16 to the shoulder flexion assembly 14.
[0135] Referring to FIGS. 10 and 11, in one embodiment, shoulder
flexion motor magnets 52 are disposed around a shaft 58 of a
shoulder flexion motor rotor 54. In this embodiment, a shoulder
flexion motor armature 55 drives the shoulder flexion motor rotor
54, which in turn drives a shoulder flexion motor pulley 56 around
a motor shaft 58. The shoulder flexion motor pulley 56 supports a
shoulder flexion belt 60, which is linked between the shoulder
flexion motor pulley 56 and a shoulder flexion belt-driven pulley
62. The shoulder flexion belt-driven pulley 62 drives a shoulder
flexion harmonic drive gearing system wave generator 64. A shoulder
flexion harmonic drive gearing system flexspline 66 rotates against
the shoulder flexion harmonic drive gearing system wave generator
64 and a shoulder flexion harmonic drive gearing system circular
spline 68, resulting in reduced speed for the joint movement. The
shoulder flexion harmonic drive gearing system flexspline 66 is
connected to the abductor interface 44, and is thus able to rotate
the shoulder flexion assembly 14 in reference to the abductor
interface.
[0136] Referring to FIG. 11, in one embodiment, a non-backdriving
clutch 70 is disposed inside the main shoulder housing 42. The
non-backdriving clutch 70 allows the prosthetic arm 10 to hold
position by locking when the prosthetic arm 10 is not moving.
[0137] Referring to FIG. 11 and FIG. 12, in one embodiment, roller
bearings 72 line the interface between an input cage 74 and an
output hex 76. When a force is applied to the shoulder abductor
interface 44, the output hex 76 locks against the bearing race 78
and the roller bearings 72. This prevents the shoulder flexion
assembly 14 from moving due to force applied to its output,
shoulder abductor interface 44. Upon the exertion of a necessary
amount of input force through the clutch input cage 74, the output
hex 76 disengages and allows the shoulder flexion assembly 14 to
move. The clutch input cage 74 and the output hex 76 are both
constrained by a clutch race 78. It should be understood by those
skilled in the art, that other mechanisms could be used to prevent
backdriving of the prosthetic arm 10, such as a dutch that locks in
one direction or a solenoid with brakes that engage when the
solenoid is powered. Additionally, although described in connection
with the shoulder flexion assembly 14, it should be understood by
those skilled in the art that the non-backdriving clutch 70 may be
included in other prosthetic joints described herein.
[0138] Referring to FIG. 13, in one embodiment, a compliance
subassembly 50, shown in FIG. 11, includes a compliance reactor 80
positioned on top of the shoulder flexion harmonic drive gearing
system circular spline 68, shown in FIG. 10, and held in place by
the clamp 82. The compliance reactor 80 measures the amount of
displacement in the compliance subassembly 50 in relation to the
position of a compliance sensor magnet 84.
[0139] Referring to FIG. 14, in one embodiment, the interior of
compliance subassembly 50 includes series elastic elements 86. The
shoulder flexion harmonic drive gearing system circular spline 68
defines the interior of the compliance subassembly 50 and is formed
to accommodate the placement of the series elastic elements 86
around an outer diameter 87 of the shoulder flexion harmonic drive
gearing system circular spline 68. The series elastic elements 86
are confined by the shoulder flexion harmonic drive gearing system
circular spline 68 and the clamp 82.
[0140] Referring to FIG. 15, the placement of the compliance
reactor 80 in relation to the series elastic elements 86 and
reactor elements 88 is shown. In this embodiment, three reactor
elements 88 are positioned around the compliance reactor 80,
equidistant to each other. One series elastic element 86 is placed
on either side of each reactor element 88. When the shoulder
flexion assembly 14 is subjected to unexpected force, such as a
sudden jolt or impact, the compliance reactor 80 and reactor
elements 88 displace from their rest positions and compress against
the series elastic elements 86. In that way, the compliance
subassembly 50 attenuates the shock being transferred to the rest
of the shoulder flexion assembly 14. The compliance reactor 80 may
also measure the amount of displacement and compliance by measuring
the movement of the compliance reactor 80 in relation to the
stationary position of the compliance sensor magnet 84.
[0141] Referring to FIG. 16, one embodiment of the humeral rotator
16 is shown. The humeral rotator 16 includes an outer bearing
carrier 90 attached to the first control housing 92, shown in FIG.
2. The first control housing 92, shown in FIG. 2, is used to
connect the humeral rotator 16 to the shoulder flexion assembly 14.
The inner rotational elements of the humeral rotator are held in
place by a damp 94, which is fastened to the outer bearing carrier
90. A humeral mount 96 passes through the clamp 94 and includes an
elbow interface 98 for attaching the elbow flexion assembly 18 to
the humeral rotator 16.
[0142] FIG. 17 shows a cross-sectional view of the humeral rotator
16. A humeral motor armature 100 drives a humeral motor rotor 102
having humeral magnets 104 disposed on its surface. The lower
portion of the motor rotor 102 engages a humeral harmonic drive
gearing system wave generator 106. A humeral harmonic drive gearing
system flexspline 108 rotates with the humeral harmonic drive
gearing system wave generator 106 against the humeral harmonic
drive gearing system circular spline 110, resulting in a speed of
rotation reduction as the humeral harmonic drive gearing system
flexspline 108 causes the humeral mount 96 to move. Bearings 111
and 113 support the humeral motor rotor 102. Bearings 112 support
the harmonic drive gearing system components 106, 108, 110. A
bearing support 114 caps the outer bearing carrier 90 between the
outer bearing carrier 90 and the first control housing 92, shown in
FIGS. 16 and 2, respectively.
[0143] Still referring to FIG. 17, the one embodiment, a humeral
potentiometer 116 of the humeral rotator 16, measures the
rotational displacement of a humeral potentiometer shaft 118 that
rotates proportionately to the humeral mount 96.
[0144] Referring to FIG. 18, the elbow flexion assembly 18 includes
an elbow joint 120 and a radial mount 122. The elbow joint 120
includes a slot 124 into which the elbow interface 98 of the
humeral rotator is inserted to facilitate connection of the elbow
flexion assembly 18 to the humeral rotator 16. The radial mount 122
provides a second electronics housing 126, in which an ACM stack
128 is located. "ACM" as used herein refers to Arm Control Module.
The radial mount 122 includes a wrist interface 130, for attachment
of the wrist rotator 20.
[0145] In some embodiments, the ACM stack 128 may be integrated
into the wrist rotator 20, as will be discussed in greater detail
below. Integrating the ACM stack 128 into the wrist rotator may be
advantageous since the wrist rotator 20 is likely to be present in
prosthetic arms for essentially all types of amputees, whereas the
elbow flexion assembly 18 may not be present, such as in a
prosthetic arm for a transradial amputee.
[0146] Referring to FIG. 19, the elbow joint 120 includes an elbow
motor armature 132 that drives an elbow motor rotor 134. Elbow
magnets 136 are disposed at one end of the motor rotor 134, and the
opposing end of the motor rotor 134 has a sun gear 138. As the
motor armature 132 drives the sun gear 138, the sun gear 138 in
turn drives four planetary gears 140 positioned equidistant from
each other around the sun gear 138. The four planetary gears 140 in
turn react against a ring gear 142, giving the elbow flexion
assembly 18 a first stage of speed reduction through an elbow
harmonic drive gearing system wave generator 148 which also acts as
the planet carrier. The elbow harmonic drive gearing system wave
generator 148 powers the elbow harmonic drive gearing system
flexspline 146, which drives against the elbow harmonic drive
gearing system circular spline 144, giving the elbow flexion
assembly 18 a second stage of reduction. The elbow harmonic drive
gearing system flexspline 146 then drives the motion of the elbow
flexion assembly 18. Bearings 150 and crossed roller bearings 152
support the outer perimeter of the elbow flexion assembly 18.
Although described with both a planetary gear system and an elbow
harmonic drive gearing system, the elbow flexion assembly 18 could
be controlled solely by a harmonic drive gearing system by changing
the gear reduction ratio.
[0147] In various embodiments, it may be desirable to avoid having
to perform additional measurement by using the measurement in the
compliance process. One example includes, in various embodiments,
where the planetary gears may be used for compliance and
measurement of load.
[0148] Referring to FIG. 20, in the embodiment shown, the radial
mount 122 is structurally fixed to the elbow joint 120, such that
when the elbow joint is actuated, the radial mount 122 moves.
[0149] Referring to FIG. 21A, an elbow compliance subassembly 154
is incorporated into the elbow flexion assembly 18. A plurality of
arms 156 extends from the center portion of the elbow compliance
subassembly 154. Each arm 156 has an elbow series elastic element
158 disposed on either side of the am 156. Similar to the shoulder
flexion assembly 14, if the elbow flexion assembly 18 is subject to
a torque, the elbow compliance subassembly 154, with its series
elastic elements 158, is capable of absorbing the shock attenuating
the torque magnitude through the rest of the elbow flexion assembly
18.
[0150] Referring to FIG. 21B, wherein like numerals represent like
elements, in some embodiments, the elbow compliance assembly 1154
may include a carrier having a magnet (not shown) disposed thereon
and having a carrier top 1838 and a carrier bottom 1840 that
connect to one another to surround the elbow harmonic drive gearing
system circular spline 1144 and that interface with a compliance
grounding member 1842. The carrier top 1838 and carrier bottom 1840
to restrict movement of the elbow harmonic drive gearing system
circular spline 1144, thereby allowing the circular spline 1144 to
operate substantially as discussed above to drive the elbow flexion
assembly 18, shown in FIG. 18. The carrier bottom 1840 includes
dips 1844 located around its periphery that slidably engage
corresponding compliance shafts 1846 of the compliance grounding
member 1842 to connect the carrier to the compliance grounding
member 1842. Each clip 1844 is positioned on a compliance shaft
1846 between two compliance springs 1848 that inhibit sliding
movement of the clips 1844 relative to the shafts 1846. The
compliance springs 1848 are preferably formed from metal and, in
some embodiments, each spring 1848 may include a plurality of
stacked spring washers. In operation, as the elbow harmonic drive
becomes loaded, the dips 1844 of the carrier slide on the
compliance shafts 1846 and load the compliance springs 1848, which
deflect in proportion to the load. A sensor (not shown) measures
the displacement of the magnet (not shown), thereby providing a
measurement of the torque carried by the elbow harmonic drive and,
therefore, the elbow flexion assembly 18, shown in FIG. 18. The
elbow compliance assembly 1154 advantageously provides improved
compliance measurements due to its metal springs 1848 as compared
to elastomeric spring designs, which have greater hysteresis.
Additionally, the carrier of the elbow compliance assembly 1154
advantageously allows the circular spline 1144 to be mounted
without any modifications that may reduce its load capacity.
[0151] Referring to FIG. 22, the ACM stack 128, includes circuit
boards 160 connected to one another by structural standoffs 162.
The structural standoffs 162 are constructed of a conductive
material, so that electrical power may be passed through the
circuit boards 160. The structural standoffs allow power to be
supplied to each circuit board 160 without conventional power
connections.
[0152] Referring to FIG. 23, the wrist rotator 20 includes a wrist
outer bearing carrier 164, a wrist clamp 166, a wrist potentiometer
168, an elbow interface 170, and a wrist flexion assembly interface
172.
[0153] Referring to FIG. 24, movement of the wrist rotator 20 is
controlled by a harmonic drive gearing system similar to that
described for the humeral rotator. A wrist rotator motor armature
174 drives a wrist rotator motor rotor 176 having wrist rotator
magnets 178 disposed to its surface. The lower portion of the wrist
rotator motor rotor 176 integrates a wrist rotator harmonic drive
gearing system wave generator 180. A wrist rotator harmonic drive
gearing system flexspline 182 rotates with the wrist rotator
harmonic drive gearing system wave generator 180 against a wrist
rotator harmonic drive gearing system circular spline 184,
resulting in reduction in the speed of rotation as the wrist
rotator harmonic drive gearing system flexspline 182 causes the
wrist flexion assembly interface 172 to move with respect to the
rest of the wrist rotator 20. Bearings 185 support the wrist
rotator motor rotor 176. Bearings 186 support the harmonic drive
gearing system components 180,182, and 184.
[0154] Still referring to FIG. 24, the wrist potentiometer 168 of
the wrist rotator 20 is disposed at one end of a wrist shaft 188
and measures the rotational displacement thereof. The wrist shaft
188 may be tubular, having an electronics channel 190 for passing
electronic power and controls through the wrist rotator 20.
[0155] Referring to FIG. 25, the wrist flexion assembly 22 includes
hand control module circuit boards 192, an input support structure
194, an output arm 196, and a hand interface 198. The input support
structure 194 connects the wrist rotator 20 with the wrist flexion
assembly 22. The output arm 196 has positive and negative flexion,
such that the output arm 196 is able to move in two opposite
directions in reference to the support structure 194. The hand
interface 198 allows the hand assembly 24 to be connected to the
wrist flexion assembly 22. Referring to FIG. 26, the wrist flexion
assembly 22, has wrist electrical connections 200 for supplying
power to a wrist flexion motor 202.
[0156] Referring to FIG. 27, in the embodiment shown, the wrist
flexion motor 202 drives a wrist flexion output gear 204, which in
turn drives a wrist flexion final stage-driven gear 206. A wrist
flexion pivot axle 208 of the output arm 196 is axially disposed
inside an opening defined by the interior of the wrist flexion
final stage-driven gear 206. Wrist flexion series elastic elements
210 are disposed in the interior of the output arm 196. Movement of
the wrist flexion final stage-driven gear 206 facilitates the
positive and negative motion of the output arm 196. A
non-backdriving clutch 212 is disposed at one end of the wrist
flexion output gear 204.
[0157] Referring to FIG. 28, the output arm 196 has a wrist flexion
drive arm 214, which is driven by the wrist flexion final
stage-driven gear 206. The end of the wrist flexion drive arm 214
accommodates a wrist flexion compliance sensor magnet 216. The
wrist flexion series elastic elements 210 are disposed on either
side of the wrist flexion drive arm 214, and the wrist flexion
series elastic elements 210 and the drive arm 214 are substantially
enclosed within the output arm 196. Similar to the elbow flexion
assembly 18 and the shoulder flexion assembly 14, if the wrist
flexion assembly 22 is subjected to a force, the wrist flexion
drive arm 214 compresses the wrist flexion series elastic elements
2 10 and attenuates the force or impact through the rest of the
wrist flexion assembly 22.
[0158] The following is a description of one embodiment of the hand
assembly. Other embodiments of the hand assembly are described and
shown elsewhere in this specification. Referring to FIGS. 29 and 30
the hand assembly 24 includes a hand support 218 for providing an
interface for connecting the hand assembly 24 to the wrist flexion
output arm 196. The hand assembly 24 also includes a thumb
structure 220, an index finger structure 222, and an MRP structure
224 replicating a middle finger 226, a ring finger 228, and a pinky
finger 230. In various embodiments, the thumb structure 220 may be
driven by two thumb drives 232 that feed into a single
differential, giving the thumb structure 220 two degrees of freedom
of movement. The index finger structure 222 may be driven by a
single index drive 234 and the MRP structure 224 may be driven by a
single MRP drive 236 that feeds a double differential. The MRP
approach allows for an indeterminate versus determinate
linkage.
[0159] Referring to FIG. 31, the index finger structure 222 (not
shown) is driven by the index drive 234 through an index drive
pulley 238, an index tensioner 240, an index tension belt 242, and
an index finger pulley 244. The index drive pulley 238 is stage
driven and transfers the torque to the index tension belt 242,
which in turn rotates the index finger pulley 244, causing the
index finger structure 222 to move. As the index tension belt 242
transfers the torque, one side of the index tension belt 242
tightens and the other side loosens, depending on which direction
the index drive pulley 238 is rotated. The index tensioner 240 is
located between the index drive pulley 238 and the index finger
pulley 244 and the index tensioner 240 displaces in relation to the
change in load to maintain the tension of the index tension belt
242. The index tensioner 240 has one side grounded and the other
side capable of displacement upon the application of a load. The
index tensioner 240 may instead ground the moveable side of the
index tensioner 240 with a spring.
[0160] Referring to FIG. 38, in another embodiment, the index
finger structure 222 is driven through an index sun shaft 350, a
set of index planets 352, an index planet carrier 354, an index
ring gear 356, and an index drive gear 358. The index drive 360
drives the index ring gear 356, turning the index planets 352, the
turning of which causes the index planet carrier 354 to rotate. The
index drive gear 358 is driven by the external teeth of the index
planet carrier 354, causing the index structure 222 to move. Any
torque transmitted by the index planet carrier 354 will react
against the index sun shaft 350 causing it to rotationally displace
the index spring 362 through the index spring mount 364. This
rotational displacement, sensed by an index potentiometer 366 can
be used to infer the load on the index finger structure 222. This
rotational displacement may be used to store elastic energy and to
provide the index finger structure 222 with a measure of compliance
that may aid in gripping and with load absorption.
[0161] Referring to FIG. 31, the thumb structure 220 is mounted on
a thumb support 246, which is driven by the two thumb differential
drives 232. The thumb structure 220 has flexural cuts 248 at its
base allowing the compliant thumb structure 220 to move when a load
is applied to it. This compliance in the thumb structure 220 may
aid in gripping and with load absorption, which may prevent the
hand assembly 24 from damaging objects (not shown) by closing
around them too quickly and forcefully.
[0162] Referring to FIG. 32, the hand assembly 24 includes an MRP
drive pulley 250 driven by the MRP drive 236. The MRP drive pulley
250 is connected through an MRP tension belt 252 to the MRP pulley
254, enabling movement of the MRP structure 224. The MRP drive
pulley 250 is stage driven and transfers the load to the MRP
tension belt 252, which in turn rotates the linked MRP structure
224 via the MRP pulley 254. As the MRP tension belt 252 transfers
torque, one side of the MRP tension belt 252 tightens as the other
side loosens. An MRP tensioner 256 located at one side of the MRP
tension belt 252 displaces in relation to the change in load to
maintain the tension of the MRP tension belt 252. This also
provides the MRP structure 224 with compliance to aid in gripping
and with load absorption, which may prevent the hand assembly 24
from damaging object s(not shown) by closing around the objects
(not shown) too quickly and forcefully.
[0163] Referring to FIG. 38, in another embodiment, the MRP finger
structures 224 are driven through an MRP sun shaft 370, a set of
MRP planets 372, an MRP planet carrier 374, an MRP ring gear 376,
and an MRP drive gear 378. The MRP drive 380 drives the MRP ring
gear 376, turning the MRP planets 372, the turning of which causes
the MRP planet carrier 374 to rotate. The MRP drive gear 378 is
driven by the external teeth of the MRP planet carrier 374, causing
the MRP structures 224 to move. Any torque transmitted by the MRP
planet carrier 374 will react against the MRP sun shaft 370 causing
it to rotationally displace the MRP spring 382 through the MRP
spring mount 384. This rotational displacement can be used to store
elastic energy.
[0164] Referring to FIG. 33 the MRP differential drive 236 includes
a main MRP drive gear 258. The MRP drive gear 258 drives a first
MRP input axle 260. The first MRP input axle 260 drives a first
differential idler gear 259 which optionally drives a middle spur
gear 262 or a differential interface gear 261. The middle spur gear
262 drives a middle pivot axle 264. The middle finger 226 is
mounted on the middle pivot axle 264 and is thus actuated by the
MRP differential drive 236. The differential interface gear 261
drives a second MRP input axle 266. The second MRP input axle 266
drives a second differential idler gear 263 which optionally drives
a ring spur gear 268 or a pinky spur gear 272. The ring spur gear
268 drives a ring pivot axle 270. The ring finger 228 is mounted on
the ring pivot axle 270 and is thus actuated by the MRP
differential drive 236. The pinky spur gear 272 drives a pinky
pivot axle 274. The pinky finger 230 is mounted on the pinky pivot
axle 274 and is thus actuated by the MRP drive 236. While the MRP
drive 236 drives the middle finger 226, the ring finger 228 and the
pinky finger 230, the gear configuration of the first input axle
260 and the second input axle 266 allows independent movement for
the under-actuated finger gear system of the MRP structures
224.
[0165] Referring to FIG. 41, in another embodiment of the hand, the
MRP differential drive 236 includes an MRP drive gear 378 which
drives a double differential allowing the MRP fingers to
conformably wrap around an object. The MRP drive gear 378 drives a
first MRP input axle 400. The first input axle 400 drives a first
differential idler gear 402 which optionally drives a middle spur
gear 404 or a differential interface gear 406. The middle spur gear
404 drives a middle pivot axle 264. The middle finger 226 is
mounted on the middle pivot axle 264 and is thus actuated by the
MRP drive 236. The differential interface gear 406 drives a second
MRP input axle 408. The second MRP input axle 408 drives a second
differential idler gear 410 which optionally drives a ring spur
gear 412 or a pinky spur gear 414. The ring spur gear 412 drives a
ring pivot axle 270. The ring finger 228 is mounted on the ring
pivot axle 270 and is thus actuated by the MRP drive 236. The pinky
spur gear 414 drives a pinky pivot axle 274. The pinky finger 230
is mounted on the pinky pivot axle 274 and is thus actuated by the
MRP drive 236. While the MRP drive 236 drives the middle finger
226, the ring finger 228 and the pinky finger 230, the gear
configuration of the first input axle 400 and the second input axle
408 allows independent movement for the under-actuated finger gear
system of the MRP structures 224.
[0166] Referring to FIG. 34 the thumb differential drives 232
control the movement of the thumb structure 220 and are driven by
thumb actuators 276. The thumb actuators 276 have nonbackdriving
thumb clutches 278 to prevent output loads from reaching and
backdriving the thumb actuators. One thumb actuator 276 drives a
first thumb output drive 280 and a first thumb output gear 282. The
first thumb output gear 282 in turn drives a first thumb transfer
gear 284, which drives a fixed differential shaft 286. The fixed
differential shaft 286 drives one thumb differential bevel gear
287. The second thumb actuator 276 drives a second thumb output
drive 288 and a second thumb output gear 290. The second thumb
output gear 290 drives a second thumb transfer gear 292, which
drives a thumb differential bevel gear 294. The two thumb
differential bevel gears 287 and 294 operate the thumb structure
220 in its two degrees of motion.
[0167] The thumb structure 220, the index finger structure 222, and
MRP structure 224 in one embodiment are covered in silicone, which
provides additional friction and aids in gripping objects. In some
embodiments, the entire hand assembly 24 may also be covered in
silicone to provide additional grip for holding objects. In other
embodiments, the silicone material may be replaced by other
compliant materials.
[0168] The hand assembly 24 is advantageous because the thumb
structure 220, index finger structure 222 and MRP structure 224
provide various degrees of freedom that allow the formation of
various grasps or grips. Additionally, the different drives for
each of the thumb structure 220, index finger structure 222 and MRP
structure 224 provide various beneficial characteristics to the
hand assembly 24. For instance, the thumb structure 220 moves
relatively slow, but with greater force than the index finger
structure 222 and MRP structure 224. The index finger structure 222
moves quickly, but with less force and is non-backdrivable. This
combination of thumb structure movement and index finger structure
movement allow the quick formation of strong hand grips.
Additionally, the combination allows for a smaller index finger
actuator, which reduces size and weight of the hand assembly 24.
Additionally, the index finger structure 222 and MRP structure 224
move similar to human fingers, which makes them look more natural
and makes them more intuitive for the user to control. The MRP
structure 224 provides only bulk control for gripping objects,
without providing for individual finger manipulation, since fine
control is not necessary for the MRP structure 224. Additionally,
the MRP structure 224 advantageously moves each finger of the MRP
structure 224 with a single actuator, eliminating excessive bulk in
the hand assembly 24. Like the index finger structure, the MRP
structure 224 moves quickly with low force but is also
non-backdrivable. Additionally, the fingers of the MRP structure
224 are highly flexible, allowing them to grip objects of varying
size and shape. The MRP structure 224 functionality allows the user
to grasp an object with the MRP structure 224 and thumb structure
220, while allowing the user to move the index finger structure 222
separately, for example, to activate a button on the object.
[0169] The various parts of the prosthetic arm apparatus 10 are, in
some embodiments, constructed from plastic or magnesium. However,
where more strength is desired, the parts may be made of aluminum,
titanium or steel. In other embodiments, the various parts of the
prosthetic arm may be constructed of other metals or plastics,
depending on the desired characteristics, including strength,
weight, compliance or other similar performance characteristics of
the various parts.
[0170] Referring to FIG. 35, a tactile feedback sensor 296 may be
positioned on the inner side of the thumb structure 220. The
tactile feedback sensor 296 may be a pressure sensor, force sensor,
a displacement sensor, or other similar sensor capable of providing
the user with feedback. Referring to FIG. 36, the tactile feedback
sensor 296 is operatively connected to a feedback actuator 298. The
tactile feedback sensor 296 may be connected to the feedback
actuator 298 by either wires or wirelessly. In operation, as the
user grips an object with the hand assembly 24, feedback sensor 296
reads the displacement of or the force exerted on the thumb
structure 220. That reading is then sent to the feedback actuator
298, which gives the user tactile feedback that indicates the
strength of the grip. Feedback actuator 298 may be placed on the
chest of the user, located on a prosthetic support apparatus 299 in
an area of tactile communication with the user, or in any other
location capable of receiving tactile feedback, such as on a user's
residuum 300. Referring to FIG. 37, the feedback actuator 298 may
be located on a foot controller 302 that is used to control hand
assembly 24.
[0171] Feedback actuator 298 may be a vibration motor, such as any
vibration motor known in the art, placed against the skin of the
user. As the user grips an object, feedback actuator 298 begins
vibrating, notifying the user how strong the object is being
gripped. As the force on or displacement of the tactile feedback
sensor 296 changes, frequency and/or amplitude of vibration may
also change, notifying the amputee of a changing grip. For example,
if a vibrating actuator 298 is placed at the chest of the user as
in FIG. 36, the user will feel the vibration at his chest.
[0172] The feedback actuator 298 may also be placed wherever the
controller for the hand assembly 24 is located. For example, if a
foot controller 302 controls the hand assembly 24, the feedback
actuator 298 may be incorporated into the foot controller 302. The
user will then receive tactile feedback of the strength of the
prosthetic grip at the same location where the controller is
located.
[0173] The actuator 298 may also be a pressure actuator that
applies pressure against the user's skin. For example, the actuator
298 may have a rod that increases pressure against the amputee's
skin as the hand assembly 24 increases its grip on an object.
[0174] Although described with a single tactile feedback sensor
296, additional tactile feedback sensors may be placed at other
locations on the hand assembly 24. For example, additional tactile
feedback sensors 296 may be placed on the index finger structure
222, the MRP structures 224, on the palm of the hand assembly 24,
or on any combination of these positions or any other location.
Each tactile feedback sensor 296 would then be operatively
connected to an associated feedback actuator 298. Multiple tactile
feedback sensors 296 and actuators 298 would provide more
sophisticated tactile feedback of the strength of the grip,
improving the control of the hand assembly 24.
[0175] In some embodiments, the tactile feedback sensor 296 may
indicate a change in pressure or force, rather than an absolute
pressure or force. For example, if the force detected by the
tactile feedback sensor 296 is constant, the feedback actuator 298
does not actuate, but if that pressure or force increases or
decreases, the actuator 298 would actuate to indicate the change in
pressure or force. Additionally, although described in terms of
grip strength, the tactile feedback sensors 296 and actuators 298
may provide a variety of other feedback in including temperature,
an operational mode of the prosthetic arm 10, surface finish of a
object, slip of an object within the hand assembly 24 or the
like.
[0176] In operation, the prosthetic arm apparatus is able to move
substantially similar to a human arm. Referring to FIGS. 29 and 30,
starting with the hand assembly 24, the thumb structure 220, index
finger structure 222, and MRP structure 224 are each driven
independent of the others, and therefore, each may be actuated
without actuating the other two structures. Both of the thumb
actuators 276 control motion of the thumb structure 220 in a
direction toward or away from the center of the palm of the hand
assembly 24, as shown in FIG. 34, through the miter gear 294 and in
a direction toward or away from the side of the palm of the hand
assembly 24, as shown in FIG. 34, through the lateral rotation
shaft, depending upon the direction and speed of rotation of each
thumb actuator 276. Thus, the thumb actuators 276, shown in FIG.
34, provide the thumb structure 220 with two degrees of freedom in
the thumb structure's movement. Coupling the two thumb actuators
276 through the differential described above to provide the two
degrees of freedom to the thumb structure 220 is advantageous over
providing a single degree of freedom with each actuator 276 because
the torque of each actuator 276 through the differential is used
for movement in both degrees of freedom, which effectively doubles
the torque of the thumb in each direction as compared to single
actuators. Specifically, the index finger structure 222 may be
actuated toward or away from the palm of the hand assembly 24,
wherein the movement path is similar to that of a human index
finger while making or releasing a fist. The middle finger 226,
ring finger 228, and pinky finger 230 of the MRP structure 224 are
actuated by the MRP differential drive 236. Additionally, the
middle finger 226, ring finger 228, and pinky finger 230 are
actuated toward or away from the palm of the hand assembly 24,
similar to the index finger structure 222. However, the middle
finger 226, ring finger 228, and pinky finger 230 are each geared
separately, such that the rate of movement of each is different,
simulating human finger movement and making the hand assembly 24
more similar to a human hand than conventional prior art prosthetic
devices.
[0177] Referring to FIG. 1, the hand assembly 24 is mounted on the
wrist flexion assembly 22 via the hand interface 198, as shown in
FIG. 25. Referring to FIG. 25, as the output arm 196 of the wrist
flexion assembly 22 is actuated, the hand assembly 24 is also
caused to move. The output arm 196 of the wrist flexion assembly 22
may be actuated pivotally about wrist flexion pivot axle 208, as
shown in FIG. 27, moving the hand interface 198 to the left or
right, and thus pivoting the hand assembly 24 in relation to the
input support structure 192.
[0178] Referring back to FIG. 1, the wrist flexion assembly 22 is
attached to the wrist rotator 20 via wrist flexion assembly
interface 172, shown in FIG. 23. Referring to FIGS. 23 and 24, when
actuated, the wrist flexion assembly interface 172 is rotated about
wrist shaft 188 in relation to 10 the wrist outer bearing carrier
164. Therefore, the wrist flexion assembly 22, and attached hand
assembly 24 are also caused to rotate in reference to the wrist
outer bearing carrier 164 by actuation of the wrist rotator 20.
Therefore, the wrist rotator 20 allows the prosthetic arm apparatus
10 to move in rotation similar to a human wrist joint.
[0179] Referring back to FIG. 1, the wrist rotator 20 is attached
to the elbow flexion assembly 18 via the wrist interface 130, shown
in FIG. 18. Referring to FIG. 20, when the elbow flexion assembly
18 is actuated, the radial mount 122 is rotated about the axis of
motor rotor 134. The wrist rotator 20, wrist flexion assembly 22,
and hand assembly 24 are thus also caused to rotate about the axis
of motor rotor 134 because they are attached at the wrist interface
to the radial mount 122. Therefore, the elbow flexion joint 18
allows the prosthetic arm apparatus 10 to move similar to flexion
extension of a human elbow joint.
[0180] Referring back to FIG. 1, the elbow flexion assembly 18 is
attached to the humeral rotator 16 via the humeral mount 96, shown
in FIG. 16. Referring to FIG. 16, actuation of the humeral rotator
16 causes the humeral mount 96 to rotate in relation to the outer
bearing carrier 90 of the humeral rotator 16. Since the elbow
flexion assembly 18, wrist rotator 20, wrist flexion 25 assembly
22, and hand assembly 24 are attached to the humeral mount 96, they
are also caused to rotate in relation to the outer bearing carrier
90. This allows the prosthetic arm apparatus 10 to rotate to
perform an arm wrestling motion.
[0181] Referring back to FIG. 1, the humeral rotator 16 is attached
to the shoulder flexion assembly 14 through the humeral interface
46, shown in FIG. 9. Referring to FIG. 9, actuation of the shoulder
flexion assembly 14 causes the main shoulder housing 42 to pivot
about the center of the abductor interface 44. Since the humeral
rotator 16, elbow flexion assembly 18, wrist rotator 20, wrist
flexion assembly 22, and hand assembly 24 are attached to the main
housing 42, they are also caused to rotate in relation to the
abductor interface 44. Therefore, the shoulder flexion assembly 14
allows the prosthetic arm apparatus 10 to move along the torso
simulating running motion.
[0182] Referring to FIG. 1, the shoulder flexion joint 14 is
attached to the shoulder abductor 12 through the shoulder flexion
assembly mount 30, shown in FIG. 5. Referring to FIG. 5, the
shoulder abductor 12 is attached to a harness that is worn by the
user via harness mount 26. When the shoulder abductor 12 is
actuated in a positive direction, the shoulder flexion assembly
mount 30 pivots away from the harness mount 26, and the user.
Similarly, by actuating the shoulder abductor in a negative
direction, the shoulder flexion assembly mount 30 is pivoted toward
the harness mount 26 and the user. Since the shoulder flexion
assembly 14, humeral rotator 16, elbow flexion assembly 18, wrist
rotator 20, wrist flexion assembly 22, and hand assembly 24 are
attached to shoulder abductor 12 at the flexion assembly mount 30,
they are also caused to pivot with the shoulder flexion assembly
mount 30.
[0183] One characteristic of the prosthetic arm apparatus described
herein is that it provides the user with substantially the same
movement capabilities and degrees of freedom of a human arm,
including two degrees of freedom in shoulder functionality.
Additionally, the modularity of each segment of the prosthetic arm
apparatus 10 provides a significant advantage over conventional
prosthetic devices. In particular, since each segment of the
plurality of segments operates independently of each other segment
of the plurality of segments, fewer segments may be used for less
severe amputees. For example, a transhumeral amputee may have full
shoulder functionality in the residuum, in which case the shoulder
abductor 12 and shoulder flexion assembly 14 segments would be
omitted from the prosthetic arm apparatus 10. The resulting
prosthetic arm apparatus 10 would include the humeral rotator 16,
the elbow flexion assembly 18, the wrist rotator 20, the wrist
flexion assembly 22, and the hand assembly 24, wherein the humeral
rotator 16 would be attached to the prosthetic harness. In some
cases, the residuum of the transhumeral amputee may even have
humeral rotation, in which case the prosthetic arm apparatus 10 may
be further simplified to include only the elbow flexion assembly
18, the wrist rotator 20, the wrist flexion assembly 22 and the
hand assembly 24, with the elbow flexion assembly 22 being attached
to the prosthetic support apparatus. Similarly, for a transradial
amputee, the prosthetic arm apparatus 10 may include only the wrist
rotator 20, wrist flexion assembly 22 and the hand assembly 24,
with the wrist rotator 20 being attached to the prosthetic support
apparatus. Additionally, in some embodiments, the prosthetic arm
apparatus 10 may be further simplified to include only the wrist
flexion assembly 22 and the hand assembly 24 when the transradial
amputee has wrist rotation in their residuum. In these embodiments,
the wrist flexion assembly 22 may be attached to the prosthetic
support apparatus. Thus, the modularity of each segment of the
prosthetic arm apparatus 10 advantageously allows for customization
of different prosthetic arm configurations for various users based
on the differing degrees of amputation of each user.
[0184] A further advantage of the present invention is the use of
non-backdriving clutches to preclude movement of the segments due
to forces exerted on the prosthetic arm apparatus 10 when not in
motion. These non-backdriving clutches may be particularly
beneficial when the segments of the prosthetic arm apparatus 10
have different strength capacities so that the clutches for
specific segments of the prosthetic arm apparatus 10 may lock those
segments while other stronger segments are actuated to lift heavy
objects. For instance, the non-backdriving dutch in the shoulder
flexion assembly 14 may be used to lock out shoulder movement while
the elbow flexion assembly 18 is actuated to lift a heavy object.
The non-backdriving clutches may also advantageously conserve power
since the non-backdriving clutches prevent motion without using
power. Thus, the power to specific segments of the prosthetic arm
apparatus 10 may be shut off, on a segment-by-segment basis, when
not in use, since the non-backdriving clutches in those segments
are locking out motion. Additionally, the non-backdriving clutches
may also save power by allowing power to the entire prosthetic arm
apparatus 10 to turned off whenever the arm is not in motion while
maintaining the prosthetic arm apparatus 10 in a locked
position.
[0185] An additional characteristic of the apparatus is that the
hand assembly includes independently moving fingers and is capable
of completing fine tasks such as pinching, grasping non-uniform
objects, and lifting small objects off flat surfaces. Also, the
tactile feedback sensor provides the user with feedback, during use
of the prosthetic arm apparatus, such as the force of a grip. The
apparatus also includes a cosmesis covering on the finger
structures, which will be discussed in greater detail below,
providing, amongst other things, grip for grasping objects. The
rigid fingernail 304, shown in FIG. 34, which may be included on
any of the finger structures, provides a backstop for the finger
cover to enhance gripping capability. The rigid fingernail 304 also
enhances gripping capability by anchoring the finger cover to the
finger and allows the user to lift small objects from a surface
with the prosthetic arm apparatus 10.
[0186] Referring to FIG. 42A, wherein like numerals represent like
elements, in some embodiments, the shoulder abductor 12 and the
shoulder flexion assembly 14 shown in FIG. 2, may be integrated as
a single shoulder unit 1416, providing both degrees of freedom
provided by the shoulder abductor 12 and shoulder flexion assembly
14 of FIG. 2. The single shoulder unit 1416 includes a shoulder
housing 1418 pivotally connected to the harness mount 1026, which
allows the shoulder unit 1416 to be connected to a prosthetic
harness (not shown) as discussed above. In some embodiments, the
shoulder housing 1418 has a smooth outer surface 1419 to shape the
shoulder unit 1416 to be similar to a human arm. The shoulder
housing 1418 is divided into a flexor portion 1420 and an abductor
portion 1422, which are movable relative to one another. The flexor
portion 1420 of the shoulder housing 1418 includes the humeral
interface 1046 for connecting the humeral rotator 16, shown in
FIGS. 1 and 2, to the shoulder unit 1416. The abductor portion 1422
of the shoulder housing 1418 is pivotally connected to the harness
mount 1026, which allows the shoulder unit 1416 to interface with a
prosthetic harness (not shown) as discussed above.
[0187] Referring to FIGS. 42B and 42C, within the housing 1418 is a
shoulder flexion drive 1424 for causing flexion motion of the
flexor portion 1420 about a shoulder flexion axis 1426 and an
abduction drive 1428 for causing abduction motion of the shoulder
housing 1418 about an abduction axis 1430. Additionally, the
housing also defines an electronics compartment 1432 for housing
control systems and circuits for the integrated shoulder unit
1416.
[0188] The shoulder flexion drive 1424, in one embodiment, includes
a shoulder flexion motor 1434 having motor shaft 1058 for driving
the shoulder flexion motor pulley 1056. The shoulder flexion motor
pulley 1056 drives the shoulder flexion belt 1060, which, in turn,
drives the shoulder flexion belt-driven pulley 1062. The shoulder
flexion belt-driven pulley 1062 drives the wave generator 1064 of a
shoulder flexion harmonic drive gearing system 1436, the output of
which is fixedly interfaced with the abductor portion 1422. Thus,
as power is transmitted through the shoulder flexion drive 1424
from the shoulder flexion motor 1434 to the output of the harmonic
drive gearing system 1436, the flexor portion 1420 rotates relative
to the abductor portion 1422 about the shoulder flexion axis 1426.
In some embodiments, the motor shaft 1058 and the wave generator
1064 are both hollow shafts to allow passage of an abductor motor
shaft 1438 and an abductor screw shaft 1440, respectively, as will
be discussed in greater detail below.
[0189] In the exemplary embodiment, the abduction drive 1428
includes the abductor motor 1036 for driving the abductor motor
shaft 1438. The abductor motor shaft 1438 is configured to drive
the abductor belt 1038 about its distal end. The abductor belt
1038, in turn, drives the abductor screw shaft 1440, which has an
abductor nut 1442 threadedly coupled thereto. The abductor nut 1442
is connected to the harness mount 1026 through a linkage 1444,
which is, in some embodiments, a four bar linkage. As power is
transmitted through the abductor drive 1426 from the abductor motor
1036 to the abductor screw shaft 1440, the screw shaft 1440
rotates. The rotation of the screw shaft 1440 causes the abductor
nut 1442 to displace axially along the screw shaft 1440, which
causes pivotal motion of the shoulder housing 1418 through the
linkage 1444 about the abduction axis 1430.
[0190] Referring to FIG. 42A, the relative movement between the
flexor portion 1420 and the abductor portion 1422 provides the
shoulder unit 1416 with a first degree of freedom similar to that
of the shoulder flexion joint 14 of FIG. 2. The abductor portion
1422 of the shoulder housing 1418 is pivotally connected to the
harness mount 1026 at the abductor joint 1034, providing the
shoulder unit with the second degree of freedom by allowing the
shoulder housing 1418 to pivot relative to the harness mount 1026
in a similar manner to that discussed above in connection with the
shoulder abductor 12 of FIG. 2. Referring to FIGS. 42B and 42C, the
integrated shoulder unit 1416 locates the shoulder flexion axis
1426 and the abduction axis 1430 relatively close to one another as
compared to separate shoulder flexion and shoulder abduction
assemblies, which provides for more intuitive motion that more
closely simulates the movement of a human shoulder.
[0191] The shoulder flexion drive 1424 and the abduction drive 1428
discussed above include coaxial motors and coaxial shafts to
minimize the size of the single shoulder unit 1416 and to reduce
the weight thereof. Thus, these exemplary single shoulder unit 1416
is beneficial because its weight relative to the separate shoulder
abductor 12 and shoulder flexion assembly 14, shown in FIG. 2.
Additionally, the single shoulder unit 1416 provides more narrow
housing 1418, which allows a more natural anatomical position of
the shoulder for a broader range of users and may reduce bumping
with the user's residuum during use. This embodiment has an
additional benefit of decreasing the weight of the prosthetic.
Additionally, as seen in FIGS. 42B and 42C, both the abduction
motor 1036 and the shoulder flexion motor 1434 may be located in
the vicinity of the electronics compartment 1432, so the
electronics for both the shoulder flexion drive 1424 and the
abduction drive 1428 may be located in the same place, which
eliminates any need to route wiring through the shoulder unit 1416.
This is advantageous since running wires across joints is a failure
mode in which the wires may crimp and break when moved. Thus, the
shoulder unit 1416 eliminates this failure mode by eliminating
wires running across the joints that could cause failure of the
prosthetic arm 1010.
[0192] Although the shoulder flexion drive 1424 and the abduction
drive 1428 have been shown in an exemplary configuration, it should
be understood by those skilled in the art that other drive
configurations may also be used to drive the single shoulder unit
1416 about the shoulder flexion axis 1426 and the abduction axis
1430. For instance, referring to FIG. 43, the shoulder flexion
motor 2434 and the abduction motor 2036 of the single shoulder unit
2416 do not need to be coaxial and they may still each be located
within the housing 2418 in the vicinity of the electronics
compartment 2432. Additionally, rather than driving the linkage
1444, shown in FIG. 42B, the worm drive 2041 may instead threadably
engage an abduction gear 2446 coupled to the harness mount 2026 to
generate pivotal movement about the abduction axis 2430.
[0193] Additionally, referring now to FIG. 44, in various
embodiments, the integrated shoulder unit 3416 may shift the
abduction output to change the location of the harness mount (not
shown) to improve mounting location and/or to allow for ninety
degrees (90.degree.) of abduction about the abduction axis 3430
without bumping with the residuum (not shown). For example, the
location of the abduction output may be changed by extending the
abduction drive 3428 with one or more additional shafts, gears,
and/or belts.
[0194] Referring to FIG. 45, the flexion assembly mount 4030 may
also be shifted away from the harness mount 4026 in the
non-integrated shoulder abductor 4012. Referring to FIG. 46, the
flexion assembly mount 4030 may also include an accommodating slot
4031 adapted to accommodate portions of the abductor joint 4034,
shown in FIG. 45. Referring back to FIG. 45, the shifted flexion
assembly mount 4030 allows the user to orient the shoulder abductor
4012 on the prosthetic support apparatus (not shown) in different
orientations while still allowing a range of motion of the shoulder
abductor 4012 of at least approximately ninety degrees
(90.degree.). This may be particularly advantageous since the
mounting orientation of the shoulder abductor 4012 may vary from
user to user, which may limit the range of abduction motion with
the non-shifted flexion assembly mount 30, shown in FIG. 6.
Additionally, in some embodiments, the shifted flexion assembly
mount 4030 may house a flex sensor plunger for detecting flexion
motion of the shoulder flexion assembly 4014.
[0195] Referring to FIG. 47A, in some embodiments of the present
invention, the prosthetic arm apparatus 10, shown in FIG. 1, may
include a shoulder free swing system 5770 including a housing 5772
having a harness mount 5026 fixedly secured thereto for attaching
to a prosthetic harness. The shoulder free swing system 5770 also
includes an arm interface 5774 rotatably secured within the housing
5772 inside a bearing 5776. The arm interface 5774 includes
mounting holes 5778 for connecting the shoulder free swing system
5770 to the shoulder unit 1416, shown in FIG. 42B, through the
abduction axis 1430 and the linkage 1444, each shown in FIG.
42B.
[0196] Referring to FIGS. 47B and 47C, within the housing 5772, the
arm interface 5774 includes a substantially circular portion 5779
that, at its outer circumference, engages the bearing 5776. The
substantially circular portion 5779 includes a plurality of locking
ramps 5780 formed therein about its inner circumference and may
also include one or more magnets 5781 disposed at the outer portion
of the locking ramps 5780. Within the substantially circular
portion 5779, the shoulder free swing system 5770 includes a
plurality of locking plates 5782, each of which has a rotation pin
5783 secured to the housing 5772 about which the locking plate 5782
may pivot. The locking plates 5782 include locking teeth 5784
configured to engage the locking ramps 5780 of the arm interface
5774. The locking plates 5782 also include cam followers 5785 for
engaging a cam plate 5786 through cam paths 5788. The cam plate
5786 is connected to a handle 5790 through an actuation plate 5792,
shown in FIG. 47A. The handle 5790 extends out of the housing 5772,
thereby allowing for user actuation thereof.
[0197] In operation, when the locking teeth 5784 of the locking
plates 5792 are disengaged from the locking ramps 5780 of the arm
interface 5774, as shown in FIG. 47B, the arm interface 5774 is
able to freely rotate with respect to the harness mount 5026, with
its substantially circular portion 5779 rotating within the bearing
5776. However, when the user moves the handle 5790 from the
position shown in FIG. 47B to the position shown in FIG. 47C, the
actuation plate 5792 rotates, which in turn rotates the cam plate
5786 and causes the locking plates 5782 to rotate until the locking
teeth 5784 engage the locking ramps 5780 of the arm interface 5774.
The one or more magnets 5781 may advantageously aid in the
engagement by drawing the locking teeth 5784 into the locking ramps
5780 and by eliminating backlash. Once the locking teeth 5784 are
engaged in the locking ramps 5780, the arm interface 5774 is no
longer able to freely move with respect to the harness mount 5026,
unless the handle 5790 is returned to the position shown in FIG.
47B. Thus, when the locking teeth 5784 are engaged, the user may
operate the prosthetic arm apparatus 10, shown in FIG. 1, in
substantially the same manner as discussed above.
[0198] The slopes of the locking teeth 5784, the locking ramps 5780
and the cam paths 5788 may advantageously be designed such that the
locking teeth 5784 will automatically become disengaged the from
the locking ramps 5780 if a torque being transmitted through the
shoulder free swing system 5770 is exceeds a maximum release
torque. For example, in some embodiments the locking teeth 5784 may
disengage the locking ramps 5780 if the torque being transmitted
through the free swing system 5770 exceeds fifty Newton meters.
Thus, the shoulder free swing system 5770 advantageously prevents
excessive loading from being transmitted through the prosthetic
device without permanently damaging any components of the
prosthetic arm apparatus 10, shown in FIG. 1.
[0199] Referring to FIG. 48A, another embodiment of a shoulder free
swing system 6770 is shown. The shoulder free swing system 6770
includes a housing 6772 having a harness mount 6026 fixedly secured
thereto for attaching to a prosthetic harness. The shoulder free
swing system 6770 also includes an arm interface 6774 rotatably
secured within the housing 6772. The arm interface 6774 includes
mounting holes 6778 for connecting the shoulder free swing system
6770 to the shoulder unit 1416, shown in FIG. 42B, through the
abduction axis 1430 and the linkage 1444, each shown in FIG.
42B.
[0200] Referring to FIG. 48B, a portion 6794 of the arm interface
6774 is rotatably secured in the housing 6772 within bearing 6776.
The portion 6794 has a tapered surface 6796 at its inner
circumference that contacts a corresponding tapered surface 6798 of
a friction plate 6800, thereby forming a tapered frictional
interface between the arm interface 6774 and the friction plate
6800. Two or more breakaway locks 6802 are loaded between the arm
interface 6774 and the friction plate 6800, each breakaway lock
6802 having a spring (not shown) that tends to separate the
friction plate 6800 from the arm interface 6774. The friction plate
6800 includes ball bearings 6804 located within grooves 6806 at its
circumference that allow linear motion along an axis 6808, but
resist rotation due to an applied torque. The breakaway locks 6802
and the geometry of the tapered surfaces 6796 and 6798 are
configured so that the friction plate 6800 and the portion 6794 of
the arm interface 6774 separate at a desired applied torque, for
example, fifty Newton meters, thereby allowing the arm interface
6774 to slowly rotate while engaging the friction plate 6800 at the
tapered surface 6798 to lower the prosthetic arm apparatus 10,
shown in FIG. 1, until it loses its potential energy. To manually
engage and/or disengage the free swing system 6770 The handle 6790
may be rotated to move a ramp 6810 linearly inward or outward along
axis 6808, thereby reengaging or disengaging, respectively, the
breakaway locks 6802 and, therefore, the free swing system
6770.
[0201] Referring now to FIG. 49, another embodiment of the wrist
rotator 1020 is shown for providing improved electronic wiring
capability to the prosthetic device. Although shown as the wrist
rotator 1020, it should be understood by those skilled in the art
that a similar configuration may be used for other rotating joints,
such as the humeral rotator 16, shown in FIG. 1. In this embodiment
of the wrist rotator 1020, the wrist rotator motor 1448, including
the wrist rotator motor armature 1174 and a driven portion 1450 of
the wrist rotator motor rotor 1176 having wrist rotator magnets
1178 disposed thereon, and the wrist harmonic drive gearing system
1452, including the wrist rotator harmonic drive gearing system
wave generator 1180, the wrist rotator harmonic drive gearing
system flexspline 1182 and the wrist rotator harmonic drive gearing
system circular spline 1184, are separated into coaxial
side-by-side units with the wrist rotator motor 1448 being
proximate to the elbow interface 1170 and the harmonic drive
gearing system 1452 being proximate to the wrist flexion assembly
interface 1172. By arranging the wrist rotator motor 1448 and the
wrist harmonic drive gearing system 1452 in the side-by-side
configuration, the electronics channel 1190 passing through the
center of the wrist rotator rotor 1176 may be formed large enough
to allow electronic wiring to be run internally through the center
of the wrist rotator 1020. Referring to FIGS. 50 and 51, the wiring
through the prosthetic arm 10, shown in FIG. 1, in some
embodiments, may run through one or more extension springs 1454, in
particular around the flexion joints, such as the elbow flexion
assembly 18 and the wrist flexion assembly 22, shown in FIG. 1,
where internal wiring is difficult or impractical.
[0202] Routing the wiring through the center of the wrist rotator
1020 eliminates the need for external wiring, thereby minimizing
any flexing movement experienced by the wiring, which can cause
wire pinching, abrasions and failure. The internal wiring also
eliminates the possibility that external wiring will become caught
on something and break. Routing the wiring through the one or more
extension springs 1454 where internal wiring is not practical,
possible or desired allows for controlled loading of the external
wiring and protects the wiring from pinching to reduce wire
failure.
[0203] Referring to FIG. 52, in another embodiment of the wrist
flexion assembly 1022, the output arm 1196 is able to move in
flexion relative to the input support structure 1194 about a
flexion axis 1456 and to move in ulnar-radial deviation relative to
the input support structure 1194 about a deviation axis 1458. Thus,
when the hand assembly 24, shown in FIG. 1, is attached to the
output arm 1196 of the wrist flexion assembly 1022, the hand
assembly 24, shown in FIG. 1, is able to move in both flexion and
ulnar-radial deviation.
[0204] Referring to FIG. 53, the wrist flexion assembly 1022
includes two wrist motors 1202, for controlling the flexion and
ulnar-radial deviation of the output arm 1196, shown in FIG. 52.
Each wrist motor 1202 drives an input geartrain 1460, which, in
turn, drives a wrist worm gear 1462. Each worm gear 1462 drives an
input gear 1464 of a wrist differential 1466. The wrist
differential 1466 includes a first bevel gears 1468 and a second
bevel gear 1470 that are rotatable about the flexion axis 1456. The
first bevel gear 1468 and the second bevel gear 1470 may be driven
by one of the input gears 1464. The wrist differential 1466 also
includes a differential body 1472 rotatably attached about the
flexion axis 1456 between the first and second bevel gears 1468 and
1470. An ulnar-radial axle 1474 extends from one side of the
differential body 1472 along the ulnar-radial axis 1458 and a third
bevel gear 1476 extends from the differential body 1472 on the
opposite side thereof. The third bevel gear 1476 is rotatable about
the ulnar-radial axis 1458 and meshes with and is driven by the
first bevel gear 1468 and the second bevel gear 1470.
[0205] In operation, the user is able to actuate wrist flexion,
wrist ulnar-radial deviation and combinations thereof by actuating
the motors 1202 in various ways. For example, referring to FIG. 54,
if the motors 1202 are driven at the same speed in opposite
directions, i.e. one is driven clockwise and the other
counterclockwise, the output arm 1196, shown in FIG. 52 will move
in flexion in one direction about the flexion axis 1456. If the
direction of each motor is reversed, i.e. from spinning clockwise
to counterclockwise and vice versa, the output arm 1196, shown in
FIG. 52, will flex in the opposite direction. Similarly, referring
to FIG. 55, if the motors 1202 are driven at the same speed in the
same direction, i.e. both are driven clockwise, the output arm
1196, shown in FIG. 52, will move in ulnar-radial deviation in one
direction about the deviation axis 1458. If the direction of each
motor is reversed, i.e. from spinning clockwise to
counterclockwise, the output arm 1196, shown in FIG. 52, will move
in ulnar-radial deviation in the opposite direction about the
deviation axis 1458. In addition to varying the direction of
rotation of the motors 1202, varying the speed of one motor 1202
relative to the other will result in a combination of flexion and
ulnar-radial deviation. Accordingly, in this embodiment, wrist
flexion and ulnar-radial deviation may both be controlled simply by
varying the direction and speed of the motors 1202.
[0206] Although the wrist flexion assembly 1022 is described as
having a differential drive 1466 for imparting wrist flexion and
wrist ulnar-radial deviation movement to the output arm 1196, it
should be understood by those skilled in the art that other drives
may be used to achieve similar capabilities. For instance,
referring to FIG. 56, the wrist flexion assembly 2022 may include a
separate wrist flexion geartrain 2478 for imparting flexion motion
to the output arm 2196 about the flexion axis 2456 and a separate
ulnar-radial geartrain 2480 for imparting ulnar-radial deviation to
the output arm 2196 about the deviation axis 2458.
[0207] Referring to FIG. 76, in another embodiment of the present
invention, a wrist flexion assembly 4022 is provided for imparting
a combination of both flexion about the flexion axis 4456 and
ulnar-radial deviation about the deviation axis 4458 to the hand
assembly 4024 in a single movement. The wrist flexion assembly 4022
includes the input support structure 4194 adapted to be connected
to the wrist rotator 20, shown in FIG. 1, in the same manner as
discussed above. The wrist support structure 4194 includes a hand
interface 4626 proximate to the hand assembly 4024 for attaching
the hand assembly 4024 to the wrist support structure 4194. The
wrist support structure 4194 houses a wrist motor 202, shown in
FIG. 26, which drives the wrist pivot axle 4208 in rotary motion
about the wrist flexion axis 4456 through an appropriate gear train
(not shown). The wrist pivot axle includes flattened end portions
4628 at each end thereof, extending outwardly from the wrist
support structure 4194 and into the hand interface 4626. Each
flattened end portion 4628 has two substantially parallel planar
surface 4630 extending parallel to the wrist flexion axis 4456. The
hand interface 4626 includes a first cam bearing 4632 fixedly
secured to the wrist support structure 4194 about the flattened end
portion 4628 of the wrist pivot axle 4208 proximate to the thumb
structure 4220 of the hand assembly 4024. The hand interface also
includes a second cam bearing 4634 fixedly secured to the wrist
support structure 4194 about the flattened end portion 4628 of the
wrist pivot axle 4208 proximate to the pinky finger 4230 of the
hand assembly 4024. Referring to FIG. 77, the first cam bearing
4632 includes a first cam profile 4636 formed therein. Referring to
FIG. 78, the second cam bearing 4634 includes a second cam profile
4638 formed therein. Referring back to FIG. 76, the hand interface
4626 also includes first and second slider blocks 4640 coupling the
hand assembly 4024 to the wrist flexion assembly 4022. The first
and second slider blocks 4640 each have a proximate end 4642 at the
hand interface 4626 and a distal end 4644 near the hand assembly
4024. Each of the first and second slider blocks 4640 has a slot
4646 formed therein that slidably receives one of the flattened end
portions 4628 of the wrist pivot axle 4208. The first and second
slider blocks 4640 include cam followers 4648 at their proximate
ends 4642 that are received within the first cam profile 4636 of
the first cam bearing 4632 and the second cam profile 4638, shown
in FIG. 78, of the second cam bearing 4634. The first and second
slider blocks 4640 are pivotally coupled to the hand assembly 4024
at their distal ends 4644 about pivot axes 4650.
[0208] In this embodiment, the hand assembly 4024 may be angled
away from the flexion axis 4456 about a wrist rotation axis 4652 to
reduce the motion that the first cam profile 4636 and the second
cam profile 4638 need to produce to achieve the desired combined
flexion and ulnar-radial deviation movement of the hand assembly
4024. In some embodiments, the hand assembly 4024 is angled
approximately thirty degrees clockwise (30.degree. clockwise)
assuming left hand user perspective from the flexion axis 4456.
[0209] Referring to FIGS. 79A-79C, in operation, the wrist motor
202, shown in FIG. 26, drives the wrist pivot axle 4208 in rotation
movement about the flexion axis 4456, which provides the hand
assembly 4024 with flexion movement. Additionally, the sliding
engagement between the flattened end portions 4628 of the wrist
pivot axle 4208 and the first and second slider blocks 4640 causes
the first and second slider blocks 4640 to pivot about the flexion
axis 4456 as the wrist pivot axle 4208 rotates. As the first and
second slider blocks 4640 pivot, the cam followers 4648, shown in
FIG. 76, follow the first cam profile 4636, shown in FIG. 77, and
the second cam profile 4638, shown in FIG. 78, which causes the
first and second slider blocks 4640 to slide relative to the wrist
pivot axle 4208. This sliding motion of each of the first and
second slider blocks 4640 causes the hand assembly 4024 to pivot
about the pivot axes 4650, shown in FIG. 76, which results in the
ulnar-radial deviation movement of the hand assembly 4024. Thus, as
the wrist motor drives the wrist pivot axle 4208, the hand assembly
4024 moves from a first position 4654, shown in FIG. 79A, in which
the hand is fully flexed and deviated in the ulnar direction, to a
second position 4656, shown in FIG. 79B, which is a neutral
position with respect to flexion movement but includes some degree
of ulnar deviation. Then, the hand assembly 4024 continues to move
until it reaches a third position 4658, shown in FIG. 79C, in which
the hand assembly 4024 is fully extended about the flexion axis
4456 and is also fully deviated in the radial direction.
[0210] Referring to FIG. 80, the first cam profile 4636, shown in
FIG. 77, and the second cam profile 4638, shown in FIG. 78, provide
for movement of the hand assembly 4024, shown in FIG. 76, along a
constrained flexion-deviation movement path 4660 that includes
components of both flexion motion and ulnar-radial deviation
motion. The constrained flexion-deviation movement path 4660 is
advantageous because the user only needs to think about controlling
a single degree of freedom, unlike the embodiments discussed above
that provide independent wrist flexion movement and ulnar-deviation
movement. Additionally, the constrained flexion-deviation movement
path 4660 is beneficial because it provides for full flexion
movement and also provides for nearly full ulnar deviation without
requiring full wrist flexion. Thus, functionality is particularly
beneficial when users use the prosthetic arm apparatus 10, shown in
FIG. 1, to pick up an object (not shown) from overhead. The
constrained flexion-deviation movement path 4660 also
advantageously allows for approximately twenty-four degrees
(24.degree.) of flexion movement without significant ulnar
deviation, which allows the user to move an object, such as a
spoon, in flexion motion without spilling its contents. This range
of flexion movement with minimal ulnar deviation provided by the
constrained flexion-deviation movement path 4660 may also be
beneficial to compensate for offset in situations where the
prosthetic arm apparatus 10, shown in FIG. 1, is mounted at an
offset, for example, to avoid the user's residuum. Additionally,
since the hand assembly 4024, shown in FIG. 76, is angled in the
neutral second position 4656, shown in FIG. 79B, pinching of the
thumb structure 4220, shown in FIG. 76, and index finger structure
4222, shown in FIG. 76, are more in line with the wrist rotation
axis 4652, which makes various tasks easier for the user, such as
turning a door knob, turning a key or the like. Thus, the
constrained flexion-deviation movement path 4660, or other similar
paths, provided by the wrist flexion assembly 4022, shown in FIG.
76, provides a variety of advantages over conventional prosthetic
devices.
[0211] Additionally, in some embodiments, the flexion axis 4456,
shown in FIG. 76, may be shifted from its neutral position to
provide various benefits. For example, the flexion axis 4456, shown
in FIG. 76, is shifted approximately thirty degrees (30.degree.)
from its neutral position. This shift provides a prosthetic hand
attached to the wrist flexion assembly 4022, shown in FIG. 76, with
a more natural appearance and may aid in positioning the hand for
various tasks, such as turning a door knob, turning a key or the
like.
[0212] Although described in terms of constrained flexion-deviation
movement path 4660, shown in FIG. 80, it should be understood by
those skilled in the art that the first cam profile 4636, shown in
FIG. 77, and the second cam profile, shown in FIG. 78, may be
formed in various configurations to achieve a variety of different
constrained movement paths. Additionally, although the constrained
flexion-deviation movement path 4660 has been described in
connection with the wrist flexion assembly 4022, the constrained
flexion-deviation movement path 4660 may also be commanded using
the flexion assembly 1022, shown in FIG. 52, by programming the
prosthetic controller to actuate the motors 1202, shown in FIG. 53,
to move the prosthetic hand assembly 24 along the same constrained
flexion-deviation path 4660.
[0213] Referring to FIG. 81, in some embodiments, a compound motion
assembly 5662 may be provided to impart two-axis motion to the
various segments discussed herein. The compound motion assembly
5662 includes an input member 5664, an output member 5666 and an
intermediate member 5668. The input member 5664 is movably coupled
to the intermediate member 5668 through a first joint 5670 and the
output member 5666 is movably coupled to the intermediate member
5668 through a second joint 5672 such that the first joint 5670 and
the second joint 5672 are arranged in series between the input
member 5664 and the output member 5666 with the intermediate member
arranged therebetween.
[0214] The input member 5664 includes an input interface 5674 at
one end thereof, two support posts 5676 extending outwardly from
the input interface to the first joint 5670 and a path member 5678
secured to the support posts 5676 at the first joint 5670. The
input interface 5674 has bolt holes 5680 or similar connection
means to allow the input member 5664 to be secured to an adjacent
segment of the prosthetic device 10, shown in FIG. 1, at the input
interface 5674. The support posts 5676 are spaced apart from one
another at a sufficient distance to accommodate the intermediate
member 5668 therebetween, as will be discussed in greater detail
below. The path member 5678 forms an arch extending over the
intermediate member 5668 and connecting one of the support posts
5676 to the other support post 5676.
[0215] Referring to FIGS. 82 and 83, the path member 5678 includes
an outer surface 5677 and an inner surface 5679 that are both
substantially spherically shaped to ensure clearance between the
path member 5678 and the output member 5666 and the path member
5678 and the intermediate member 5668, respectively. The path
member 5678 also includes a base portion 5682 at each end thereof
for interfacing with the support posts 5676, shown in FIG. 81. Each
base portion 5682 includes mounting holes 5684 for fastening the
path member 5678 to the support posts 5676, shown in FIG. 81. The
path member 5678 has a fixed path profile 5686 formed therethrough
and extending along at least a portion of the arch of the path
member 5678 between the two base portions 5682. The fixed path
profile 5686 has a curvature that is selected to define the
compound motion of the output member 5666 relative to the input
member 5664, as will be discussed in greater detail below. The
fixed path profile 5686 may be asymmetrical, as shown, or may
instead be symmetrical depending upon the desired compound
motion.
[0216] Referring back to FIG. 81, as discussed above, the path
member 5678 is preferably a separate element fixedly secured to the
support posts 5676 so that the path member 5678 may advantageously
be removed and replaced as will be discussed below. However, those
skilled in the art should understand that the path member 5678 may
instead be integrally formed as part of the input member 5664.
[0217] Referring to FIGS. 81 and 84, the intermediate member 5668
of the compound motion assembly 5662 is pivotally coupled to the
input member 5664 at the first joint 5670, such that the
intermediate member 5668 pivots about a first axis 5688 of the
first joint 5670. The intermediate member is suspended between the
support posts 5676 and between the input interface 5674 and the
path member 5678 by the first joint 5670 to ensure clearance as the
intermediate member 5668 pivots. The intermediate member 5668 is
coupled to the output member 5666 at the second joint 5672 such
that the output member is able to pivot about a second axis 5690
defined by the second joint 5672. In some embodiments, the first
joint 5670 and the second joint 5672 are arranged relative to one
another such that the first axis 5688 and the second axis 5690 are
substantially coplanar, while in other embodiments, the first axis
5688 and the second axis 5690 may not be substantially coplanar.
The intermediate member 5668 may have a spherical shape at the end
proximate the path member 5678 to ensure clearance between the
intermediate member 5668 and the path member 5678.
[0218] Referring to FIGS. 85 and 86, in some embodiments, the
intermediate member 5668 may include a housing 5692 enclosing a
drive arrangement 5694 for actuating the compound motion assembly
5662. The drive arrangement 5694 includes a motor 5696 coupled to
an output shaft 5698 through a gear train, which may include one or
more reduction gears 5702, a strain wave gearing system having a
circular spline 5704, a wave generator 5706, a wave generator
bearing 5708 and a flex spline 5710 or any other similar gearing
system for transmitting torque from the motor 5696 to the output
shaft 5698. The output shaft 5698 extends outwardly through both
sides of the housing 5692 and is rotatable supported therein by
bearings 5712. Each end of the output shaft 5698 is secured to the
output member 5666 to form the second joint 5672, shown in FIG. 85,
with the second axis 5690 being the axis of rotation of the output
shaft 5698. Securing the output shaft 5698 at each end to the
output member 5666 provides increased torque to the output member
5666 when the drive arrangement 5694 is actuated. However, in some
embodiments, the output member 5666 may only be secured to the
output shaft 5698 at one end thereof, thereby simplifying the drive
arrangement 5694. In these embodiments, the other end of the output
shaft 5698 may support the output member 5666 rotatably
thereon.
[0219] Referring to FIG. 85, power to the motor 5696 is preferably
supplied through a circuit board 5714 secured within housing 5692.
The circuit board 5714 may include a shaft position sensor 5716
disposed thereon for monitoring movement of the output shaft 5698.
For instance, the shaft position sensor 5716 may be an optical
sensor having an infrared emitter and receiver that transmits
infrared light at a reflective cam surface 5718 fixed to the output
shaft 5698 and receives the reflected light signal, thereby
enabling position detection. The circuit board 5714 may also
include a temperature sensor (not shown) for monitoring the
temperature of the motor 5696 to ensure safe operation. The circuit
board 5714 may be connected to an external controller (not shown)
for supplying power and control to the motor 5696 and for receiving
and processing position signals from the shaft position sensor 5716
and the temperature sensor (not shown). In some embodiments, a
single cable (not shown) may be used to connect the circuit board
5714 to the controller (not shown). This single cable (not shown)
may reduce cable flex as the compound motion assembly 5662
actuates, thereby reducing cable failure, which may result in
possible damage to the compound motion assembly 5662 or any
components connected thereto. Preferably, the controller (not
shown) shorts the motor 5696 when the compound motion assembly 5662
is not being actuated to prevent back-driving of the compound
motion assembly 5662, which may also result in possible damage to
the compound motion assembly 5662 or any components connected
thereto.
[0220] Referring back to FIG. 81, the output member 5666 includes
two output arms 5720, each secured to one end of the output shaft
5698, shown in FIG. 85, and extending outwardly past the path
member 5678 to an output interface 5722. The two output arms 5720
are connected by a follower member 5724 having an extension 5726
that is accommodated within the fixed path profile 5686 of the path
member 5678. The extension 5726 may be, for example, a cam bearing
for slidably engaging the fixed path profile 5686, as will be
discussed below. Preferably, the follower member 5724 is removably
coupled to the output arms 5720 by bolts 5728 or the like. The
output interface 5722 includes bolt holes 5680 or similar
connection means to allow the output member 5666 to be secured to
an adjacent segment of the prosthetic device 10, shown in FIG. 1,
at the output interface 5722. For example, referring to FIG. 87,
the compound motion assembly 5662 may be implemented as a
prosthetic wrist having the hand assembly 24 mounted to the output
interface 5722. Preferably, when implemented as a prosthetic wrist,
the cosmesis 1566, shown in FIGS. 67 and 69, would also extend over
the compound motion assembly 5662 to protect the moving components
of the compound motion assembly 5662 from contamination due to dirt
of the like.
[0221] Referring to FIGS. 88A-88F, in operation, as the motor 5696,
shown in FIG. 85, is actuated, the output shaft 5698, shown in FIG.
85, turns causing pivotal movement of the output member 5666 at the
second joint 5672 about the second axis 5690. As the output member
5666 pivots at the second joint 5672, the extension 5726 of the
output member 5666 slides within the fixed path profile 5686. As
the extension 5726 slides within the fixed path profile 5686, the
curvature of the fixed path profile 5686 moves the extension 5726
laterally causing pivotal movement of the intermediate member 5668
relative to the input member 5664 at the first joint 5670. This
pivotal movement also results in pivotal movement of the output
member 5666 about the first axis 5688 of the first joint 5670 since
the output member 5666 is attached to the intermediate member 5668.
Thus, the compound motion assembly 5662 provides compound motion of
the output interface 5722 relative to the input interface 5674
about both the first axis 5688 and the second axis 5690 using a
single motor 5696, shown in FIG. 85. Therefore, the compound motion
assembly 5662 requires only a single degree of freedom as a control
input, which reduces the cognitive burden on the user while still
providing a complex output movement.
[0222] As discussed above, the fixed path profile 5686 has a
curvature that is selected to define the compound motion of the
output member 5666 relative to the input member 5664. Referring to
FIG. 89, the fixed path profile 5686, shown in FIG. 81, produces
compound motion path 5730 having pivotal movement about both the
first axis 5688 and the second axis 5690. It should be understood
by those skilled in the art that the fixed path profile 5686 may be
changed to produce alternative motion paths 5732, depending upon
the desired movement of the output interface 5722, shown in FIG.
81. Thus, when the compound motion assembly 5662, shown in FIG. 87,
is used with a prosthetic hand 24, shown in FIG. 87, the fixed path
profile 5686 may be formed to provide the flexion-deviation
movement path 4660, shown in FIG. 80, having all of the advantages
discussed above in connection therewith. Alternatively, the fixed
path profile 5686 may instead be formed to provide the hand
assembly 24, shown in FIG. 87, with an alternative movement path
5732 having another advantageous path of movement for different
user needs.
[0223] Referring back to FIG. 81, as discussed above, the path
member 5678 is preferably removably attached to the support posts
5676. This advantageously allows the path member 5678 to be easily
removed from the compound motion assembly 5662 and replaced if
damaged or if an alternative motion path 5732, shown in FIG. 89, is
desired for the output interface 5722. Thus, the compound motion
assembly 5662 may advantageously be reprogrammed for different uses
or different users by the swapping of a single part. Additionally,
when implemented as a prosthetic wrist, as shown in FIG. 87, the
compound motion assembly 5662 may be switched from a right handed
to left handed prosthetic wrist, and vice versa, by changing only
the path member 5678 and the output arms 5720, each of which is
advantageously removably attached to the compound motion assembly
for easy removal and installation.
[0224] Referring to FIG. 90, in some embodiments, the compound
motion assembly 5662 and any metal structure secured thereto, such
as hand assembly 24, shown in FIG. 87, may be incorporated into a
first antenna 5818 for communication between the arm control module
(ACM) stack 5128 and an external device such as a control unit for
the prosthetic arm apparatus 10, shown in FIG. 1. The compound
motion assembly 5662 forms a radiating element 5820 of the first
antenna 5818 and a first printed circuitboard 5822 of the ACM stack
5128 connected to the radiating element 5820 provides the remainder
of the antenna 5818.
[0225] Referring to FIG. 91, the compound motion assembly 5662
includes a grounding disc 5824 at the interface with the ACM stack
5128, shown in FIG. 90, that electrically isolates the radiating
element 5820 from the first printed circuitboard 5822. A screw
connection 5826 passes through the grounding disc 5824 to allow the
printed circuitboad 5822 to be secured thereto with a screw (not
shown). The screw connection 5826 advantageously facilitates both a
mechanical connection between the printed circuitboard 5822 and the
radiating element 5820 as well as an electrical connection between
the radiating element 5820 and the antenna matching network circuit
on the printed circuitboard 5822.
[0226] Thus, referring to FIG. 92, the compound motion assembly
5662, as well as any metal structure secured thereto, provides the
radiating element 5820 for the first antenna 5818, while the rest
of the electrical components of the first antenna 5818 may be
housed on the printed circuitboard 5822. In some embodiments, the
impedance of the compound motion assembly 5662, as well any metal
structure secured thereto, is matched to that of the transceiver of
the printed circuitboard 5822 to provide for efficient energy
transfer. By providing the entire compound motion assembly 5662,
and any metal structure attached thereto, as the radiating element
5820, with its impedance matched to that of the transceiver, the
first antenna 5818 necessarily provides a better and more robust
antenna than substantially any antenna that could be housed within
the wrist structure itself. Therefore, the first antenna 5818 may
advantageously be implemented as the primary communication channel
for the prosthetic arm apparatus 10, shown in FIG. 1, transferring
critical commands, such as commands relating to prosthetic
movement, to and from the ACM stack 5128, shown in FIG. 90.
Additionally, due to the size of the radiating element 5820, the
signaling to and from the first antenna 5818 is less susceptible to
multi-path interference, which often presents a significant problem
for short-range communications within buildings due to signal
reflections and the like.
[0227] Although multi-path interference is not a significant
problem for the first antenna 5818 due to the size of the radiating
element 5820, it may, in some embodiments, be a problem for
short-range communications within buildings. In particular, typical
short-range communication frequencies, for example, approximately
2.5 GHz, do not typically pass through human torsos. Additionally,
signal reflection within a building may result in signals that are
the same, except 180 degrees out of phase, being received by an
antenna, which causes the signals randomly and periodically to
completely cancel.
[0228] Accordingly, referring to FIGS. 93 and 94, a second antenna
5828 for overcoming the transmission issues associated with
in-building interference may be formed entirely on a second printed
circuitboard 5830 of the ACM stack 5128, shown in FIG. 90. The
second antenna 5828 includes a first chip antenna 5832 and a second
chip antenna 5834 mounted on the printed circuitboard 5830 at an
angle of approximately 90 degrees relative to one another. The
first chip antenna 5832 and the second chip antenna 5834 are
connected to a transceiver 5835, shown in FIG. 93, of the second
antenna 5828 through a combiner 5836 that passively combines
signals received by the first and second chip antennas 5832 and
5834 by taking only the stronger of the two signals. In some
embodiments, the combiner 5836 may be a 90 degree phase combiner,
while in other embodiments the combiner may include some other
phase angle. Additionally, although the first and second chip
antennas 5832 and 5834 have been described as being offset
approximately 90 degrees relative to one another, one skilled in
the art should understand that the first and second chip antennas
5832 and 5834 may be offset at other angles to suit some other need
while still achieving substantially the same benefit as that
achieved with the 90 degree offset.
[0229] The offset angle between the first chip antenna 5832 and the
second chip antenna 5834 advantageously allows the second antenna
5828 to mitigate multi-path interference by capturing signals in
different phase angles. Thus, the second antenna 5834 may
advantageously provide the prosthetic arm apparatus 10, shown in
FIG. 1, with a secondary antenna for less critical signals where
some interference is acceptable. For example, the second antenna
5828 may be used for calibration of the prosthetic arm apparatus
10, shown in FIG. 1, via a personal computer or for downloading
data logs from the prosthetic arm apparatus 10, shown in FIG. 1, to
the personal computer. Thus, while some embodiments of the present
invention may implement only the first antenna 5818, shown in FIG.
90, or the second antenna 5828, other embodiments may implement
both the first and second antennas 5818 and 5828 to cooperate and
provide a more robust communication system.
[0230] Although described herein in the context of a prosthetic arm
and/or prosthetic hand, it should be understood that the antennas
described herein may be used for communication in various other
devices and are not necessarily limited to use in a prosthetic arm/
prosthetic hand.
[0231] Referring to FIG. 95, in some embodiments, compound motion
assembly 6662 may include a path member 6678 having the fixed path
profile 6686 formed on each peripheral edge thereof. In this
embodiment, the output member 6666 includes two extensions 6726,
each extension 6726 engaging one of the fixed path profiles 6686.
This embodiment operates in substantially the same manner as the
embodiments discussed above. However, this embodiment may
advantageously provide for a more compact compound motion assembly
6662.
[0232] Referring back to FIG. 81, although described in connection
with the detailed embodiments herein, it should be understood by
those skilled in the art that the compound motion assembly 5662 may
advantageously be implemented in various industrial and
manufacturing environments, or the like. Thus, the compound motion
assembly may provide equipment and/or machinery having complex
compound motion paths 5730, shown in FIG. 89, controlled through
simplified single degree of freedom inputs. In these embodiments,
the compound motion assembly 5662 may be scaled up or down in size
to meet specific or desired requirements. Additionally, path
members 5678 may be swapped in and out to alter the compound motion
path 5730, shown in FIG. 89. The input interface 5674 may
advantageously be secured to a floor, a table or similar
workstation to provide a fixed frame of reference from which the
output interface 5722 is actuated. Additionally, the output
interface 5722 may advantageously be adapted to accommodate various
industrial or manufacturing tools thereon.
[0233] Still referring to FIG. 81, although the compound motion
assembly 5662 has been described as having a drive arrangement
5694, shown in FIG. 85, for actuating the compound motion assembly
5662, some embodiments of the present invention may not be powered,
thereby simplifying the compound motion assembly 5662 by
eliminating the drive arrangement 5694, shown in FIG. 85. For
example, FIG. 96 shows an embodiment of a non-powered compound
motion assembly 7662. The compound motion assembly 7662 may be
moved by hand and locked in a desired position through the use of a
brake 7736, or the like. Additionally, some non-powered embodiments
of the compound motion assembly 7662 may include a handle 7734 to
provide for easier manual actuation of the compound motion assembly
7662.
[0234] Referring to FIG. 57A and FIG. 57B, in various embodiments,
the non-backdriving clutch 1070 may replace spacers of the input
cage 1074 with springs 1482 between the rollers 1072. The springs
1482 push the rollers 1072 apart and into contact with both the
race 1078 and the output polygon 1484, which may be an output hex
1076. Thus, when a backdriving torque (not shown) is applied to the
output hex 1076 to friction lock the rollers 1072 between the
output hex 1076 and the bearing race 1078, the rollers 1072 are
already contacting both the race 1078 and the output hex 1076,
thereby substantially eliminating backlash, i.e. a slight rotation
of the output polygon 1076, when the backdriving torque (not shown)
is applied. Thus, the non-backdrivable clutch 1070 imparts a
frictional lock, which additional backdriving torque (not shown)
through the output hex 1076 will not overcome. Additionally, as
discussed above in connection with FIG. 12, in various embodiments,
the non-backdriving clutch 1070 may unlock itself through the
application of an input load through the input cage 1074.
Variations of this embodiment may include, but are not limited to,
additional or fewer springs 1482, additional or fewer rollers 1072
or a differently shaped race 1078. For example, in various
embodiments, the relative position of the output hex 1076 and the
race 1078 may be shifted, i.e., rather than the hollow, circular
race 1078 with the output polygon 1484 inside, in various
embodiments, the clutch may include an outer hollow output polygon
surrounding a circular race. Additionally, although shown as a coil
spring, it should be understood by those skilled in the art that
the springs 1482 may be formed in various configurations and/or
from a variety of metal or elastomeric materials to provide the
force for separating the rollers 1072.
[0235] Referring to FIG. 57C, in some embodiments, the
non-backdriving clutch 1070 may be integrated in combination with a
gearbox 1483 within a single gearbox housing 1485. In this
embodiment, the gearbox 1483 may include an input 1487 for engaging
and being driven by a motor (not shown) and an output 1489 that
transmits torque from the motor (not shown) to the associated
prosthetic joint or segment. For example, the combination gearbox
1483 may be used for the two thumb drives 232, the index drive 234
and the MRP drive 236, all shown in FIGS. 31-34, so that these
drives may be assembled and disassembled as a single unit. This
advantageously allows sensitive clutch components to be isolated
and protected within a single housing 1485. Additionally, this
allows the gearbox 1485 to built separately with the clutch 1070
and gearbox 1483 therein and later assembled into the hand assembly
2024, shown in FIG. 58A, as will be discussed below.
[0236] Referring to FIG. 58A, in some embodiments, the hand
assembly 2024 may include a plurality of self-contained
subassemblies 2850 to advantageously make assembly and/or
disassembly of the hand assembly 2024 easier. The self-contained
subassemblies 2850 may be built in parallel and then quickly
assembled into the full hand assembly 2024. The self-contained
subassemblies 2850 may include, for example, the thumb drives 2232,
the index drive 2236 and the MRP drive 2234, each of which may
include the integrated gearbox 1483 and clutch 1070, shown in FIG.
57C. The self-contained subassemblies 2850 may also include a first
MRP differential 2854 and a second MRP differential 2856 that may
be fully assembled as complete units and easily dropped into the
hand assembly 2024. The self-contained subassemblies 2850 may also
include the thumb assembly 2220, the thumb differential 2852 as
well as each of the index finger 2222, middle finger 2226, ring
finger 2228 and pinky finger 2230. This advantageously allows the
four finger subassemblies to be assembled as complete units and
then assembled into the hand assembly 2024 and retained therein
using a single pin 2858. Thus, the plurality of self-contained
subassemblies 2850 may advantageously make assembly and/or
disassembly of the hand assembly 2024 easier and may reduce build
time, since each self-contained subassembly 2850 may be completed
separately and simultaneously.
[0237] Still referring to FIG. 58A, in some embodiments, the index
finger structure 2222 may include a base portion 2860 and a tip
portion 2862, which are connected in a pivotal connection at a
knuckle joint 2864. The base portion 2860 connects to the hand
assembly 2024 through a pin hole 2865 and includes a gear segment
2866 fixedly connected at its lower end, which interfaces with the
index drive 2234 to allow for controlled movement of the base
portion 2860 about the pin 2858.
[0238] Referring to FIG. 58B, within the index finger structure
2222 is disposed a two-part linkage element 2868 that includes a
non-circular pin hole 2870 at its lower end and pivot bar 2872 at
its distal end. The pivot bar 2872 connects to the tip portion 2862
at an offset location from the knuckle joint 2864. The non-circular
pin hole 2870 is disposed adjacent to the pin hole 2865 and allows
the pin 2858 to pass therethough when the index finger structure
2222 is assembled to the hand assembly 2024, with a corresponding
non-circular portion 2874, shown in FIG. 58A, of the pin 2858
engaging the non-circular pin hole 2870. In operation, when
actuated, the index drive 2234 drives the base portion 2860 of the
index finger structure 2222 through the gear segment 2866. As the
base portion 2860 moves, the two-part linkage 2868 remains grounded
due to contact between the non-circular pin hole 2870 with the
non-circular portion 2874 of the pin 2858. This, in turn, causes
the pivot bar 2872 to move the tip portion 2862 relative to the
base portion 2860, thereby achieving the movement of the index
structure 2222 that is kinematically deterministic. Since the
grounding of the two-part linkage 2868 is achieved through
insertion of the pin 2858, it may advantageously be accomplished at
essentially any point during assembly of the hand assembly 2024.
Additionally, it also advantageously allows the index structure
2222 to be replaced without requiring disassembly of the hand
assembly 2024 or a substantial part thereof.
[0239] Referring to FIG. 59, an embodiment for output load sensing
through a drive 1486 having a worm gear 1488, such as the shoulder
abduction drive 3428 of FIG. 44, is shown. Including one or more
worm gears 1488 in the drive 1486 is beneficial because the worm
gear 1488 may itself prevent backdriving. The worm gear 1488 may be
arranged on a splined shaft 1490 between a first spring 1492 and a
second spring 1494. The splined shaft includes a plurality of
splines 1496 arranged axially around the surface of the splined
shaft 1490 and a shaft input 1498 portion, which may be rotated
directly by a motor (not shown) or through a gear train or the
like. The worm gear 1494 is tubular and has an interior surface
1500 designed to slidably interface with the splines 1496 of the
splined shaft 1490 such that the worm gear 1488 may slide axially
along the surface of the splined shaft 1490. The worm gear 1488
meshes with an output gear 1502 such that when the splined shaft
1490 is caused to rotate through its shaft input portion 1498, the
splined shaft 1490 rotatably drives the worm gear 1488 through the
splines 1496 which, in turn, drives the output gear 1502. When a
load (not shown) is applied to the drive through the output gear
1502, for example, if the user is lifting an object, the load will
generate a torque T at the output gear 1502. Although the torque T
will not cause the worm gear 1488 to rotate, the torque T may cause
the worm gear 1488 to displace axially along the splined shaft 1490
compressing one of the first spring 1492 or the second spring 1494,
depending upon the direction of displacement. Thus, by designing
the drive system 1486 with the first spring 1492 and the second
spring 1494 of known spring constants, the compliance, i.e. the
displacement of the worm gear 1488, may be measured to estimate the
output load (not shown). This drive system 1486 for output load
sensing is particularly beneficial since the compliance is still
present or active while the worm gear 1488 is not being rotated,
but is instead acting as a non-backdriving element.
[0240] The prevention of backdriving with the various systems
discussed above is beneficial because it allows the user to
maintain a position of the prosthetic arm 10, shown in FIG. 1,
while under a load (not shown). However, referring to FIGS. 60A and
60B, in some embodiments, it may be desirable to provide the
various arm segments with break-away mechanisms 2504 that will
separate the drive output from the drive input to prevent damage to
the drive system if the load becomes too large. The break-away
mechanism 2504 may include an input shaft 2506, an output shaft
2508 and two break-away spacers 2510 that are held in contact with
the input shaft 2506 and output shaft 2508 by a compression member
2512. The input shaft 2506 and the output shaft 2508 each include a
shaft body 2514 and a torque transmission tab 2516 extending
axially outward from the shaft body 2514 between the break-away
spacers 2510. The compression element member 2512 surrounds the
break-away spacers 2510 and sandwiches the torque transmission tabs
2516 therebetween. The compression member 2512 may be, for example,
a snap ring, a round metal ring, an o-ring, multiple o-rings, a
coil spring, or the like. The compression member 2512 applies a
preset compressive force to the breakaway spacers 2510.
[0241] In operation, the input shaft 2506 of the break-away
mechanism 2504 is rotated by a motor (not shown) or the like to
generate a desired movement of the prosthetic arm 10, shown in FIG.
1. Thus, the torque transmission tab 2516 of the input shaft 2506
rotates and transmits the rotation through the break-away spacers
2510 to the torque transmission tab 2516 of the output shaft 2508
as long as the torque required to cause rotation of the torque
transmission tab 2516 of the output shaft 2508 is not large enough
to overcome the preset compressive force provided by the
compression member 2512. If the torque is large enough to overcome
the preset compressive force, the torque transmission tab 2516 will
push the break-away spacers 2510 apart and the torque transmission
tab 2516 will rotate between the break-away spacers 2510 without
transmitting torque therethrough. Thus, the break-away mechanism
2504 may prevent torque above a preset level from being transmitted
through the drive system, where it can damage the drive system
components. Accordingly, the break-away mechanism 2504 may limit
the amount of torque applied to sensitive parts of the various
drive systems of the prosthetic arm 10, shown in FIG. 1, and may,
therefore, impart a longer lifespan on the prosthetic arm.
[0242] Referring to FIG. 61A, another embodiment of a breakaway
mechanism 3504 includes an input ring 3518 and an output ring 3520
connected by a detent ring 3522. The breakaway mechanism 3504 may
be connected between two prosthetic arm segments, for example, the
input ring 3518 may be connected to the shoulder unit 1416, shown
in FIG. 42A, and the output ring 3520 may be connected to the
humeral rotator 16, shown in FIG. 1. Referring to FIGS. 62B and
62B, in some embodiments, the input ring 3518, output ring 3520 and
the detent ring 3522 each includes an alignment marker 3524 on its
outer surface 3526 to indicate proper positioning of the breakaway
mechanism 3504.
[0243] Referring to FIG. 61B, the output ring 3520 includes a
central hub 3528 having an outer surface 3529 with a plurality of
spring fingers 3530 radiating therefrom. Each spring finger 3530
has a first detent 3532 and a second detent 3534 along its length
and a pin 3536 at its distal end 3538. The input ring 3518 includes
a plurality of detents 3540 around the circumference of its inner
surface 3542, within which the pins 3536 of the spring fingers 3530
may engage, as will be discussed in greater detail below. The
detent ring 3522 includes a plurality of detent pins 3544 located
partway between the inner surface 3542 of the input ring 3518 and
the outer surface 3529 of the output ring 3520. The detent pins
3544 engage the first detents 3532 of the spring fingers 3530
during normal operation of the breakaway mechanism 3504, i.e. when
torque is being transmitted through the breakaway mechanism
3504.
[0244] However, referring to FIG. 62A, if an overtorque situation
occurs, the pins 3536 at the distal ends 3538 of the spring fingers
3530 will pop out of the ring detents 3540 so that the torque will
not be transmitted back to the input ring 3518. Additionally,
referring to FIG. 62B, the overtorque situation will also cause the
alignment markers 3524 to move out of alignment. The user may then
realign the alignment markers 3524 to transmit torque through the
breakaway mechanism 3504.
[0245] Referring to FIG. 63A, the user may also intentionally
disengage the torque transmission by moving the alignment marker
3524 on the detent ring 3522 up to engage the breakaway mechanism
3504 in freeswing. As seen in FIG. 63B, this configuration entirely
disengages the spring fingers 3530 from the input ring 3518,
thereby allowing the output ring 3520 to rotate freely without
driving the upstream components through the input ring 3518. Thus,
this embodiment of the breakaway mechanism 3504 is advantageous
because it also allows for the user to engage freeswing of the
prosthetic arm 10, shown in FIG. 1.
[0246] These break-away mechanisms discussed above are beneficial
because they prevent damage to the prosthetic arm apparatus 10 and
increase user safety under high loading situations. Additionally,
the break-away mechanisms are advantageous in that once the
break-away mechanisms break under high loading, they may be reset
by the user without the need to see a prosthetic technician.
[0247] As discussed above, various embodiments of the prosthetic
arm 10, shown in FIG. 1, include feedback mechanisms for compliance
and position sensing, such as potentiometer 48, shown in FIG. 10.
Referring now to FIG, 64, in some embodiments, the prosthetic arm
10, shown in FIG. 1, may include other feedback mechanisms, for
example, a magnetic position sensor 1546. In these embodiments, at
least one magnetic strip 1548 may be attached about the
circumference of an inner surface 1550 of a rotatable drive
component 1552. The magnetic strip 1548 includes a plurality of
magnets 1554 of known length L1 arranged in series, each having a
north pole N and a south pole S. Thus, the magnetic strip 1548
generates a magnetic field having a repeating pattern of
alternating north poles N and south poles S. The magnetic position
sensor 1546 is arranged to detect this magnetic field generated by
the magnetic strip 1548. In operation, the rotatable drive
component 1552 rotates, which causes the magnetic strip 1548 to
rotate, thereby moving the portion of the magnetic strip 1548 being
detected by the magnetic position sensor 1546. The magnetic
position sensor 1546 detects this change in the magnetic field as
the magnetic strip 1548 rotates from each north pole N to each
south pole S and vice versa. Since the length L1 of each magnet
1554 is known, the detected changes in the magnetic field between
each north pole N and/or each south pole S may be converted into
the distance of rotational movement of the rotatable drive
component 1552. Thus, the change in position of the rotatable drive
component 1552 may be detected. The magnetic position sensor 1546
is also advantageous because it does not contact the rotating drive
component 1552 and, therefore, will not experience contact wear due
to the rotation of the rotatable drive component 1552.
[0248] Referring to FIG. 65, in some embodiments, two magnetic
position sensors 1546 may be used to detect the magnetic fields
generated by the first magnetic strip 1548 and a second magnetic
strip 1556 arranged next to each other around the circumference of
the inner surface 1550 of a rotatable drive component 1552. A
length L2 of each magnet 1558 of the second magnetic strip 1556 is,
in some embodiments, different than the length L1 of the magnets of
the first magnetic strip 1548. This difference in length allows for
the magnetic position sensors 1546 to sense unique combinations of
magnetic field values from the first magnetic strip 1548 and the
second magnetic strip 1556 over the circumference of the inner
surface 1550. Each unique magnetic field value may correspond to a
position of the drive component 1552 and, therefore, absolute
position of the drive component 1552 may be detected by the two
magnetic position sensors 1546.
[0249] In practice, the hand assembly 24, shown in FIG. 1, and
particularly, the fingers of the hand assembly 24, i.e. the thumb
structure 220, index finger structure 222, middle finger 226, ring
finger 228 and pinky finger 230, all shown in FIG. 3, come into
contact with objects frequently and, therefore, may be susceptible
to wear and damage. Thus, referring to FIG. 66, it may be desirable
for the prosthetic hand assembly 1024 to include removable fingers
1560. In this embodiment of the prosthetic hand assembly 1024, the
removable fingers 1560 may be removed to allow for easier
replacement of damaged fingers 1560 and also, to allow for easily
customizable or tailored finger lengths for different user.
[0250] Each removable finger 1560 is driven in substantially the
same manner as the fingers of the previously discussed embodiments.
However, the removable fingers 1560 pivot about a common finger
shaft 1562, rather than the individual pivot axles discussed in
connection with FIG. 33. In some embodiments, end caps 1564 cover
each end of the common finger shaft 1562 to prevent dirt or other
contaminants from getting into the gear trains of the hand assembly
1024 and also to ensure that the common finger shaft 1562 does not
become axially displaced unintentionally. In operation, either end
cap 1564 may be removed from the hand assembly 1024 and the common
finger shaft 1562 may be extracted to free the removable fingers
1560. Each finger 1560 may then be removed and replaced
individually, as required.
[0251] As discussed above, the fingers 1560 of the hand assembly
1024 come into contact with objects frequently and are, therefore,
susceptible to wear. Thus, referring to FIG. 67, some embodiments
of the present invention may include a cosmesis 1566 for covering
the hand assembly 1024 to reduce wear of the hand assembly 1024 and
the fingers 1560, in particular. The cosmesis 1566 may be formed
from silicone or a similar material, such as a urethane, to improve
the grip capabilities of the hand assembly 1024 to assist with the
various grasping and pinch functions of the hand, thereby,
providing additional functionality.
[0252] In use, the cosmesis 1566 may wear more quickly around the
fingers 1560 and the thumb structure 1220. Therefore, in some
embodiments the cosmesis 1566 may separate into two or more
sections to allow high wear areas to be replaced more frequently
than low wear areas. For instance, referring to FIG. 68A, in some
embodiments, the cosmesis 2566 includes a separate palm section
2568 covering the hand support 2218, finger sections 2570 covering
each finger 2560 and a thumb section 2572 covering the thumb
structure 2220. Thus, the finger sections 2570 and thumb section
2572 may each be replaced separately from the palm section 2568.
Although shown as having separate finger sections 2570 and thumb
section 2572, in various embodiments, the cosmesis 2566 may also
include only two sections, for example, the finger sections 2570
and the thumb section 2572 may be combined into one section and the
hand support 2218 may be covered by the separate palm section
2568.
[0253] Referring to FIG. 68B, in some embodiments of the present
invention, the fingers 3560 may be provided with geometric features
3574, such as slots, in their outer surfaces 3576 that may accept
corresponding geometric interlocks 3578 provided on the inner
surface 3580 of the cosmesis 3566. This interlocking geometry may
resist shear loads on the cosmesis 3566, thereby preventing the
cosmesis 3566 from slipping off of the fingers 3560. Additionally,
with respect to the hand cosmesis, fine pinch and other functions
may require a structural backing at the tips of the fingers 3560
and thumb structure 3220. Therefore, in some embodiments, the
geometric features 3574 of the fingers 3560 and thumb structure
3220 may each include a fingernail apparatus 579, shown in FIG. 40.
The fingernail apparatus 579, shown in FIG. 40, interacts with the
finger and thumb structure cosmesis 3566 to anchor the cosmesis
3566 of the fingers 3560 and thumb structure 3220, thereby
mitigating and/or preventing the cosmesis 3566 from rolling over on
the tips of the fingers 3560 and thumb structure 3220.
[0254] Referring to FIG. 69, the palm section 1568 of the cosmesis
1566 may also be formed to resist slippage due to shear loads. For
instance, a palm side 1582 of the cosmesis 1566 may be formed with
a tacky inner surface 1584. In some embodiments, the material of
the cosmesis 1566 itself will provide the tacky inner surface 1584,
for example, silicone or a urethane material may be naturally
tacky. In other embodiments, a tacky surface coating may be applied
to the cosmesis to form the tacky inner surface 1584. Thus, as
objects being held are pressed against the palm side 1582 of the
cosmesis 1566, the tacky inner surface 1584 is pressed against the
hand support 218, shown in FIG. 29, thereby resisting slippage. In
some embodiments, a back side 1586 of the cosmesis 1566 is formed
with a slippery inner surface 1588 to facilitate installation and
removal of the cosmesis 1566. For example, the slippery inner
surface 1588 may be formed by applying a surface modifying coating
to the cosmesis, or applying a surface texture to the cosmesis
1566. For example, to install the cosmesis 1566 onto the hand
support 218, shown in FIG. 29, the cosmesis 1566 may be pulled down
and away from the palm so that the slippery inner surface 1588 of
the back side 1586 slides along the hand support 218, while the
tacky inner surface 1584 of the palm side 1582 is pulled away from
the hand support 218. Thus, the cosmesis 1566 may be easily slid
onto the hand support 218. To remove the cosmesis 1566, the palm
side 1582 may again be pulled away from the hand support 218 while
the cosmesis 1566 is pulled toward the fingers 1560, thereby
allowing the cosmesis 1566 to slide easily off the hand support
218.
[0255] Referring to FIG. 70, in some embodiments, the cosmesis 4566
may include corrugations 4812 having grooves 4814 wherein a
thickness of the material forming the cosmesis 4566 is
substantially less than the thickness of material of the rest of
the cosmesis 4566. The corrugations 4812 and grooves 4814 may
advantageously be positioned in locations where the prosthetic arm
apparatus 10, shown in FIG. 1, moves and flexes to allow the
cosmesis 4566 to flex along with the arm movement without bunching,
wrinkling, tearing or the like. Additionally, although the
corrugations 4812 are shown only in a wrist area for simplicity, it
should be understood by those skilled in the art that the
corrugations 4812 may be positioned in other locations where
substantial movement is anticipated such as the fingers. In some
embodiments, the cosmesis 4566 may also include raised ridges 4816
having a material thickness that is greater than substantially the
rest of the cosmesis 4566 to provide improved grip in desired
regions such as at the fingertips of the cosmesis 4566.
[0256] Referring to FIG. 71, in some embodiments, the fingers 1560
may include one or more additional functions. For example, one or
more fingers 1560 may include a thermal sensor 1590 disposed
thereon to determine the temperature of an object (not shown)
brought into contact with the finger 1560. The signal from the
sensor 1590 may be transmitted to a controller (not shown) for the
prosthetic arm 1010 and displayed to the user as will be discussed
in greater detail below. In some embodiments, temperature detection
may be provided by forming the cosmesis 1566, or a portion thereof,
from a temperature sensitive polymer, such as a polymer with a
thermochromic color changing additive therein or thermochromic
liquid crystal that allows a variety of colors to be shown as
temperature changes, which will change color depending upon the
temperature of the cosmesis 1566. For example, the cosmesis 1566
may change from one color to another if a present temperature is
exceeded. This temperature sensing functionality may be used to
determine the temperature of an object (not shown) in the hand 1024
and to warn the user of a high temperature or low temperature
condition to mitigate the threat of burns or other harm.
[0257] Referring to FIG. 72A, another embodiment of the thumb
structure 2220 is shown for providing thumb compliance detection.
The thumb structure includes a thumb base 2592 and a thumb tip
2594, which are each substantially rigid and are joined together by
an elastomeric spring 2596. In some embodiments, the interface
between the thumb tip 2594 and the elastomeric spring 2596 includes
one or more alignment features 2598 to ensure proper alignment of
the thumb tip 2594 with the elastomeric spring 2596. Similarly, the
interface between the thumb base 2592 and the elastomeric spring
2596 also includes one or more alignment features 2598 to ensure
proper alignment of the thumb base 2592 and the elastomeric spring
2596.
[0258] Referring to FIG. 72B, within the thumb structure 2220, the
thumb base 2592 includes a pivotal interface tube 2600 extending
upward into a central bore 2602 of the elastomeric spring 2596. A
pivot shaft 2604, having a magnet 2606 disposed at its lower end
2608, is arranged with the pivotal interface tube 2600 and extends
upwardly therefrom into a central bore 2610 in the thumb tip 2594
of substantially the same diameter as the pivot shaft 2604. Below
the pivot shaft 2604 within the thumb base 2592 is arranged a Hall
effect sensor 2612 on a sensor bracket 2614. The sensor bracket
2614 includes a wire channel 2616 to facilitate wiring the Hall
effect sensor 2612 to the prosthetic control circuits (not shown).
Referring to FIG. 72C, in operation, when a load L is applied to
the thumb tip 2594 the elastomeric spring 2596 compresses on the
side of the thumb structure 2220 opposite the applied load L,
allowing the thumb tip 2594 to tilt. The tilt of the thumb tip 2594
causes a corresponding tilt of the pivot shaft 2604 within the
pivotal interface tube 2600, thereby displacing the magnet 2606
disposed on the lower end 2608 of the pivot shaft 2604. The Hall
effect sensor 2612 detects this displacement of the magnet 2606,
which can be correlated to the applied load L on the thumb tip
2594. By detecting the various loads on the thumb structure 2220,
the user may ensure that objects are not gripped so hard that they
could break and that the thumb is not subjected to loads that could
cause failure of the thumb structure 2220.
[0259] Referring to FIG. 73, wherein like numerals represent like
elements, another embodiment of the thumb structure 3222 is shown
for providing thumb compliance detection. In this embodiment, a
helical spring 3597 replaces the elastomeric spring 2596, shown in
FIG. 72B, between the thumb base 3592 and the thumb tip 3594.
Additionally, a collar 3599 is disposed between the helical spring
3597 and the pivot shaft 3604 with a small clearance between a ball
3605 of the pivot shaft and the collar 3599. As with the previous
embodiments, the pivot shaft 3604 has magnet 3606 disposed at its
lower end 3608 and extends upwardly therefrom into a central bore
3610 in the thumb tip 3594 and is secured therein. Below the pivot
shaft 3604 within the thumb base 3592 is arranged sensor 3612 for
detecting movement of the magnet 3606. In operation, when a load L
is applied to the thumb tip 3594, the ball 3605 contacts the collar
3599 and the helical spring 3597 compresses on the side of the
thumb structure 3222 opposite the applied load L, allowing the
thumb tip 3594 to tilt about the center of the ball 3605. The tilt
of the thumb tip 3594 causes a corresponding tilt of the pivot
shaft 3604, thereby displacing the magnet 3606 disposed on the
lower end 3608 of the pivot shaft 3604. The sensor 3612 detects
this displacement of the magnet 3606, which can be correlated to
the applied load L on the thumb tip 3594. By detecting the various
loads on the thumb structure 3222, the user may advantageously
ensure that objects are not gripped so hard that they could break
and that the thumb is not subjected to loads that could cause
failure of the thumb structure 3222.
[0260] Referring to FIG. 74, in some embodiments, the humeral
rotator 1016 may include a yolk 1618, rather than the cantilever
mounting interface shown in FIG. 16, for interfacing with the elbow
flexion assembly 1018. The yolk 1618, interfaces with a first side
1620 and a second side 1622 of the elbow flexion assembly 1018 to
provide increased strength to the interface when compared to the
cantilever mounting interface shown in FIG. 16, which only
interfaces with one side of the elbow flexion assembly 1018.
[0261] Referring to FIG. 75A, in some embodiments of the present
invention, the prosthetic arm 3010 may be provided with a status
indicator 3620. In some embodiments the status indicator 3620 may
include, but is not limited to, one or more LEDs 3622 arranged on
the hand assembly 3024. However, in other embodiments, the one or
more LEDs 3622 may be located in various locations. The one or more
LEDs 3622 may be configured to communicate a variety of information
to the user, including, but not limited to, one or more of the
following, battery power level, an operational mode of the
prosthetic device, faults, alarms, alerts, messages, and/or the
like. Additionally, although shown as one or more LEDs 3622 the
status indicator 3620 may, in other embodiments, include a digital
display and/or user interface, which may be arranged on the
prosthetic device 3010, built into the prosthetic device 3010
and/or may be a separate display unit (for example, as shown in
FIG. 75B as 3630), and in some embodiments, may be a unit worn
similarly to a wrist watch or bracelet as shown in FIG. 75B as
3630. However, in other embodiments, the unit 3630 may be a
portable unit that may be worn or carried near the user, for
example, but not limited to, dipped on clothing, belt and/or
attached to the user, and/or carried in a pocket either in the
user's clothing and/or in a separate bag and/or pack. In some
embodiments, the unit 3630 may be a PDA (personal data assistant),
smart phone or other electronic device configured to communicate
with the prosthetic device 3010 by way of a wireless communications
protocol, including, but not limited to, RF and Bluetooth.RTM..
[0262] Thus, in some embodiments, it may be desirable to include
both a separate display unit and one or more LEDs 3622, where, for
example, but not limited to, the one or more LEDs 3622 may be used
to display one or more critical piece of information to the user,
while the separate display unit, 3630 may provide a greater variety
of information in more detail.
[0263] Referring to FIG. 75C, an embodiment of the wrist rotator
4020 having the ACM stack 4128 housed therein is shown. The wrist
rotator 4020 includes a housing 4738 having an input interface
4739, such as the elbow interface 170, shown in FIG. 23, and an
output interface 4740, such as the wrist flexion assembly interface
172, shown in FIG. 23, at either end thereof. The housing also
includes a user interface 4741 formed therein and in communication
with the ACM stack 4128. The ACM stack 4128 controls operation of
each segment of the prosthetic arm apparatus 10, shown in FIG. 1,
including the wrist rotator 4020 and, therefore, integrating the
ACM stack 4128 into the wrist rotator 4020 may be advantageous
since the wrist rotator 4020 is likely to be present in prosthetic
arms for essentially all types of amputees, whereas other segments
may not be present, such as in a prosthetic arm apparatus for a
transradial amputee.
[0264] The user interface 4741 may include the status indicator
4620 for communicating status information of the prosthetic arm
apparatus 10, shown in FIG. 1, from the ACM stack 4128 to the user.
The user interface 4741 may also include one or more user inputs
4742, such as buttons, switches, dials or the like for changing
and/or customizing the status information that is conveyed from the
ACM stack 4128 through the status indicator 4620.
[0265] The status indicator 4620 may include one or more LEDs 4622
configured to communicate the status information from the ACM stack
4128 to the user through illumination of the LEDs 4622. For
instance, specific information may be communicated to the user
through simple illumination, flashing patterns, color patterns and
various combinations thereof. The LEDs 4622 may include a battery
alert 4744 for alerting the user of a low power condition.
Similarly, the LEDs 4622 may include a system alert 4746 for
alerting the user of a system fault condition. The LEDs may include
a mode indicator 4748, for example, to indicate whether the
prosthetic arm apparatus 10, shown in FIG. 1, is in mode for
controlling arm movement or a mode for controlling hand movement.
Additionally, the LEDs 4622 may include an array 4750 of LEDs 4622
for providing specific information to the user on the current
operational mode of the prosthetic device. For instance, when in a
hand control mode, each LED 4622 in the array 4750 may represent a
different sub control mode of the prosthetic device 10, shown in
FIG. 1, such as different grip movements. In some embodiments, LEDs
4622 may be arranged at multiple locations around the circumference
of the wrist rotator 4020 so that at least some of the LEDs 4622
remain visible to the user as the prosthetic arm 10, shown in FIG.
1, moves during operation.
[0266] Preferably, the user interface 4741 is formed from a
rubberized material to allow actuation of the one or more user
inputs 4742 therethrough and to prevent contaminants such as dirt,
dust, water and the like from contacting and damaging the wrist
rotator 4020. Additionally, the rubberized material preferably
includes one or more translucent portions 4752 in the region of the
status indicator 4620 for allowing light from the LEDs 4622 to pass
therethrough and may also include one or more symbols printed on
the translucent portions 4752 for conveying status information to
the user.
[0267] Referring to FIGS. 75D and 75E, as discussed above, the
wrist rotator 4020 having the ACM stack 4128 and the user interface
4741 is preferably a modular unit that may connect either to a
transradial mount 4754 for a transradial amputee or the elbow
flexion assembly 18, shown in FIG. 1, for a transhumeral or
shoulder disarticulated amputees. To facilitate the connection, the
input interface 4739 includes a captive spanner screw 4756 having
male threads, an alignment pin 4758 and one or more torque
transmission pins 4760. The transradial mount 4754 (or the elbow
flexion assembly 18, shown in FIG. 1) includes female threads for
engaging the male threads of the captive spanner screw 4756, a left
hand alignment hole 4762, a right hand alignment hole 4764 and one
or more torque transmission holes 4766.
[0268] To assemble the wrist rotator 4020 to the transradial mount
4754 or the elbow flexion assembly 18, shown in FIG. 1, power and
communication wiring connections are first made between the parts.
Then, the alignment pin 4758 of the wrist rotator 4020 is
registered in either the left hand alignment hole 4762 or the right
hand alignment hole 4764 of the transradial mount 4754 (or the
elbow flexion assembly 18, shown in FIG. 1), depending upon whether
the prosthetic arm apparatus 10, shown in FIG. 1, is to be a
left-handed or right-handed prosthesis, respectively. A spanner
wrench may then be used to engage the spanner screw 4756 and thread
the male threads of the spanner screw 4756 into the female threads
of the transradial mount 4754 (or the elbow flexion assembly 18,
shown in FIG. 1). As the male threads engage the female threads,
the torque transmission pins 4760 engage the torque transmission
holes 4766 until the spanner screw 4756 is fully seated. This
connection advantageously provides a universal interface between
the wrist rotator 4020 and either the transradial mount 4754 or the
elbow flexion assembly 18, shown in FIG. 1. The connection is also
advantageously universal for both left-handed and right-handed
prosthetic devices. For example, the using the right hand alignment
hole 4764 provides for a desired range of motion for a right-handed
prosthetic device, such as two hundred seventy degrees
(270.degree.). Using the left hand alignment hole 4762 provides a
range of motion for a left-handed prosthetic device that is the
mirror opposite of the range of motion for the right-handed
prosthetic device, for example two hundred seventy degrees
(270.degree.) in the opposite direction of rotation. Additionally,
when using either the left hand alignment hole 4762 or the right
hand alignment hole 4764 in the connection, the user interface 4741
is advantageously maintained in the view of the user.
[0269] Referring back to FIGS. 75A and 75B, in some embodiments of
the present invention, the prosthetic arm 3010 may be provided with
an emergency switch 3624 which may turn off power to the system and
thus engage the various brakes and/or clutches in the prosthetic
arm 3010. In some embodiments, the emergency switch 3624 is a chin
switch that the user may activate with their chin.
[0270] In some embodiments, another safety mechanism of the
prosthetic arm 3010 may include an auto release mechanism 3768 for
manually opening a grip of the prosthetic hand 3024. The auto
release mechanism 3768 may be a button, switch or the like located
on the back of the prosthetic hand 3024, which, when actuated,
causes the prosthetic hand 3024 to open. Preferably, the auto
release mechanism 3768 is located under the cosmesis 1566, shown in
FIG. 67, and actuated therethrough, to prevent contaminants such as
dirt, dust, water and the like from contacting and damaging the
auto release mechanism 3768. The auto release mechanism 3768 is
electrically coupled to a power source (not shown) of the
prosthetic arm 3010, such as a battery, and to motor control
circuits, such as the hand control module circuit boards 192, shown
in FIG. 25, that control actuation of the motors within the
prosthetic hand 3024, such as the two thumb drives 232, the index
drive 234 and the MRP drive 236, all shown in FIGS. 31-34.
Preferably, the auto release mechanism 3768 is connected to the
motor control circuits for the two thumb drives 232, the index
drive 234 and the MRP drive 236, all shown in FIGS. 31-34, in
parallel to provide redundancy to the auto release mechanism 3768
so that even if one circuit fails, the others will still cause the
associated prosthetic fingers to open. In some embodiments,
additional redundancy may be provided to the auto release mechanism
3768 by connecting the auto release mechanism 3768 to the motor
control circuit boards 192 through at least two switches, with only
one switch being required to cause the prosthetic hand 3024 to
open.
[0271] In operation, the user may depress the auto release
mechanism 3768, which, in turn, actuates the switch or switches on
the hand control module circuit boards 192. Actuation of the switch
or switches causes power to be supplied from the power source (not
shown) to the two thumb drives 232, the index drive 234 and the MRP
drive 236, all shown in FIGS. 31-34, through the hand control
module circuit boards 192, which causes the prosthetic hand 3024 to
open. The speed at which the prosthetic hand 3024 opens may be
tuned within the hand control module circuit boards 192 and is
preferably less than approximately five (5) seconds. In some
embodiments, the speed at which the prosthetic hand 3024 opens may
even more preferably be set to less than approximately three (3)
seconds. Thus, the user may advantageously actuate the auto release
mechanism 3768 to release the grip of the prosthetic hand 3024 if
it is closed and/or becomes stuck in hazardous and/or harmful
situations; for example, if the grip becomes stuck around a car
door handle, a bus handle, while shaking a child's hand or any
other similar situation.
[0272] Although the auto release mechanism 3768 has been described
as being electrically coupled to the power source (not shown) of
the prosthetic arm 3010 and to the hand control module circuit
boards 192, in other embodiments, the auto release mechanism 3768
may include a separate power source (not shown) and/or separate
motor control circuits (not shown) located within the prosthetic
hand 3024 to provide additional redundancy. Additionally, in other
embodiments, the auto release mechanism 3768 may be a mechanical
system rather than an electrical system, for example, the auto
release mechanism 3768 may be a crank or the like for manually
opening the prosthetic hand 3024.
[0273] The prosthetic arm apparatus of the present invention has a
variety of benefits over conventional prosthetic devices, such as
the modularity of each segment of the prosthetic arm apparatus as
discussed above, which allows the formation of customized
prosthetic devices for different users. In particular, each segment
of the prosthetic arm apparatus 10 contains all of the actuators
for that segment so that it may be removed as a separate unit. For
instance, the hand assembly includes all of the finger actuators
therein, allowing it to be connected and/or removed as a separate
unit. Additionally, various degrees of freedom of the hand assembly
are particularly beneficial because they allow the formation of
various grasps or grips.
[0274] Although the invention has been described in the context of
a prosthetic arm, an apparatus according to the elements of this
invention could be used in other robotic tools, such as those used
in manufacturing and/or teleoperations, where an operator is not
connected directly to the controlled device. For example the
prosthetic arm apparatus may be used for teleoperation in hazardous
environments and/or hazardous activities, for the detonation of
explosive devices or the like. In these environments, the
prosthetic arm apparatus may provide a more intuitive interface for
the user since the user will already be familiar with the natural
movements of the arm, which may make control translation of the
prosthetic arm apparatus easier.
[0275] While the principles of the invention have been described
herein, it is to be understood by those skilled in the art that
this description is made only by way of example and not as a
limitation as to the scope of the invention. Other embodiments are
contemplated within the scope of the present invention in addition
to the exemplary embodiments shown and described herein.
Modifications and substitutions by one of ordinary skill in the art
are considered to be within the scope of the present invention.
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