U.S. patent application number 13/854723 was filed with the patent office on 2014-03-27 for robotic prosthesis alignment device and alignment surrogate device.
This patent application is currently assigned to ORTHOCARE INNOVATIONS LLC. The applicant listed for this patent is David Alan Boone, Ben Gilbert Macomber. Invention is credited to David Alan Boone, Ben Gilbert Macomber.
Application Number | 20140088726 13/854723 |
Document ID | / |
Family ID | 41198567 |
Filed Date | 2014-03-27 |
United States Patent
Application |
20140088726 |
Kind Code |
A1 |
Boone; David Alan ; et
al. |
March 27, 2014 |
ROBOTIC PROSTHESIS ALIGNMENT DEVICE AND ALIGNMENT SURROGATE
DEVICE
Abstract
A robotic prosthesis alignment device is disclosed that may
automatically move the alignment of a prosthesis socket in relation
to a prosthesis shank. The robotic prosthesis alignment device
provides automatic translation in two axes. The robotic prosthesis
alignment device includes angulation mechanics that automatically
provide for plantarflexion, dorsiflexion, inversion, and eversion
of the foot and shank with respect to the prosthesis socket. A
surrogate device is also disclosed that can replicate the alignment
achieved with the robotic prosthesis alignment device.
Inventors: |
Boone; David Alan; (Seattle,
WA) ; Macomber; Ben Gilbert; (Shoreline, WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Boone; David Alan
Macomber; Ben Gilbert |
Seattle
Shoreline |
WA
WA |
US
US |
|
|
Assignee: |
ORTHOCARE INNOVATIONS LLC
Oklahoma City
OK
|
Family ID: |
41198567 |
Appl. No.: |
13/854723 |
Filed: |
April 1, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12502162 |
Jul 13, 2009 |
8409297 |
|
|
13854723 |
|
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61080120 |
Jul 11, 2008 |
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Current U.S.
Class: |
623/24 ; 623/33;
901/9 |
Current CPC
Class: |
A61F 2/60 20130101; A61F
2002/704 20130101; Y10S 901/09 20130101; A61F 2/70 20130101; A61F
2002/7635 20130101; A61F 2/76 20130101; A61F 2/68 20130101; A61F
2002/7645 20130101; A61F 2002/705 20130101; A61F 2002/7615
20130101; A61F 2/80 20130101; A61F 2002/5023 20130101; A61F
2002/7695 20130101; A61F 2002/5018 20130101 |
Class at
Publication: |
623/24 ; 623/33;
901/9 |
International
Class: |
A61F 2/76 20060101
A61F002/76; A61F 2/80 20060101 A61F002/80 |
Goverment Interests
STATEMENT OF GOVERNMENT LICENSE RIGHTS
[0002] This invention was made with Government support under Grant
Nos. RHD047119 and RHD055709, awarded by the National Institute of
Child Health and Human Development. The U.S. Government has certain
rights in the invention.
Claims
1. A robotic prosthesis alignment device, comprising: a translation
assembly comprising a first slide deck and a second slide deck that
translates in a different direction to the first slide deck; an
angulation assembly comprising a first wedge and a second wedge,
each wedge being separately capable of rotation; and one or more
drivers to move the first and second slide decks and rotate the
first and second wedges.
2. The device of claim 1, wherein the translation assembly provides
displacement of an object attached to the translation assembly
along a two dimensional plane.
3. The device of claim 1, wherein the angulation assembly provides
displacement by tilting an object attached to the angulation
assembly.
4. The device of claim 1, wherein the movement of the first and
second slide decks is linear.
5. The device of claim 1, wherein each wedge comprises a circular
member that varies in height around the circumference.
6. The device of claim 1, further comprising a driver having a
revolution counter and a processor that correlates a translational
position to the number of revolutions.
7. The device of claim 1, further comprising a driver having a
revolution counter and a processor that correlates an angular
position to the number of revolutions.
8-9. (canceled)
10. A prosthesis system, comprising: a prosthesis socket for
receiving an amputated limb; a prosthesis shank attached to the
prosthesis socket; a prosthesis foot attached to the lower end of
the prosthesis shank; and a robotic prosthesis alignment device of
claim 1 attached at the joint between the prosthesis socket and the
prosthesis shank and/or at the joint between the prosthesis shank
and the prosthesis foot, the robotic prosthesis alignment device
comprising encoders that provide a translational position and
angular position of the prosthesis.
11-17. (canceled)
18. The prosthesis of claim 10, further comprising a computer in
communication with the robotic prosthesis alignment device, wherein
the computer computes a gait cycle profile from the translational
and angular position.
19. The prosthesis of claim 18, further comprising a memory device
having stored therein correlations of linear positions and angular
positions to a plurality of gait cycle profiles.
20. The prosthesis of claim 18, further comprising a torque sensor
attached to the prosthesis that provides torque measurements to
generate a profile of a gait cycle.
21. The prosthesis of claim 18, wherein the computer compares a
gait cycle profile generated from translational and angular
positions to a gait cycle stored in a database and computes a
translational position and angular position that approximately
matches the gait cycle profile stored in the database.
22. A method for automatically controlling the alignment of a
prosthesis, comprising: measuring a first translational and angular
position of a mechanical joint on a prosthesis and providing the
measurements to a computer; determining, via the computer, a first
gait cycle profile from the first translational and angular
position of the mechanical joint; obtaining, via the computer, a
second gait cycle profile stored in a computer memory; comparing,
via the computer, the first gait cycle profile to the second gait
cycle profile and determining differences; calculating, via the
computer, a second translational position and angular position
calculated to reduce the differences between the first and second
gait cycle profiles; and moving the mechanical joint to the second
translational position and angular position.
23-25. (canceled)
26. The method of claim 22, wherein the first gait cycle profile is
determined by searching a database having stored therein profiles
of gait cycles correlating to translational positions and angular
positions.
27. The method of claim 22, wherein the first gait cycle profile is
determined by torque forces measured along the posterior/anterior
plane and right/left planes.
28. The method of claim 22, wherein the mechanical joint attaches a
prosthesis socket to a prosthesis shank or a prosthesis shank to a
prosthesis foot.
29. The method of claim 22, wherein the mechanical joint comprises
a robotic prosthesis alignment device, comprising: a translation
assembly comprising a first slide deck and a second slide deck that
translates in a different direction to the first slide deck; an
angulation assembly comprising a first wedge and a second wedge,
each wedge being separately capable of rotation; and one or more
drivers to move the first and second slide decks and rotate the
first and second wedges.
30. A surrogate device for transferring an alignment to a
prosthesis, comprising: a first wedge comprising marks, wherein the
marks are determinative of a position on the wedge; and a second
wedge comprising marks, wherein the marks are determinative of a
position on the wedge, wherein the first and second wedge are
rotationally positionable with respect to each other such that
aligning a mark of the first wedge with a mark on the second wedge
results in a predetermined angular position.
31-33. (canceled)
34. A method for maintaining the alignment of a prosthesis,
comprising: setting the angular alignment of a prosthesis, wherein
the angular alignment is controlled by a robotic device having
first and second wedges that are automatically and rotationally
positionable with respect to each other; moving the wedges with
respect to each other to achieve an alignment; taking a measurement
of the positions of the two wedges in the alignment; and assembling
a surrogate device having first and second wedges that are
assembled to correlate with the measured positions of the wedges of
the robotic device to achieve an alignment achieved with the
robotic device.
35. The method of claim 34, further comprising setting the
translational alignment of the prosthesis, wherein the
translational alignment is controlled by a robotic device having
first, second and third slide decks that are automatically and
translationally positionable with respect to each other and taking
a measurement of the positions of the slide decks, and assembling
the surrogate device having two decks that are assembled to
correlate with the measured positions of the slide decks of the
robotic device.
36-39. (canceled)
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 12/502,162, filed Jul. 13, 2009, which claims
the benefit of U.S. Provisional Application No. 61/080,120, filed
on Jul. 11, 2008, each of which applications is herein expressly
incorporated by reference in its entirety.
BACKGROUND
[0003] Referring to FIG. 1, a conventional prosthesis 10 includes a
prosthesis socket 60 into which the amputated limb is placed. The
prosthesis socket 60 is connected to a prosthesis shank 30. The
prosthesis shank 30 is further connected to a prosthesis foot 20
which bears the weight and makes contact with the ground. The
conventional prosthesis 10 includes an adjustable connection,
normally between the prosthesis socket 60 and the prosthesis shank
30. For example, the prosthesis shank 30 can have a coupling 40
with an upper end having a concave hemispherical surface. The
prosthesis socket can have a pyramid adaptor 50 at the lower end
thereof which fits into an aperture provided in the concave surface
of the coupling 40. The pyramid adapter 50 includes a surface
curved to match the concave surface of the coupling 40. With this
configuration, the prosthesis socket 60 can be articulated forward
and backward and from side to side with respect to the prosthesis
shank 30 and foot 20 to align the prosthesis socket 60 and
prosthesis shank 30 to an optimal position that is both efficient
and comfortable for the wearer of the prosthesis 10.
[0004] A computerized prosthesis alignment system is disclosed in
U.S. Application Publication Nos. 2008/0139970 and 2008/0140221,
incorporated herein expressly by reference for all purposes. These
application publications disclose a torque sensor 104 and control
module 106 that provide a means for manually aligning a prosthesis.
See FIG. 4 of the publications. The torque sensor 104 is
incorporated with a pyramid adaptor (see FIG. 6A of the
publications) that then attaches to the lower part of the
prosthesis socket 60 and is capable of measuring forces experienced
by the prosthesis socket 60. A computer system is then able to
analyze the forces and provide feedback to a prosthetist via a
graphical user interface, in the form of specific instructions for
aligning the prosthesis to an optimum setting. For example, because
the alignment of the pyramid adaptor is adjusted using four set
screws (elements 117a-d in FIG. 5 of the publications), the
computer system can provide instructions, such as the amount of
turns required of the set screws to achieve the proper
alignment.
[0005] The referenced publications further disclose a method of
maintaining the alignment once the optimal alignment is achieved.
This method relies on the use of a substitute pyramid adaptor that
is dimensionally similar to the torque sensor so that it can simply
be substituted for the torque sensor. (See element 105 in FIG. 5 of
the publications.) The method, however, relies on removing the set
screws that hold the alignment according to a specific sequence so
as to transfer the substitute pyramid adaptor for the torque sensor
without upsetting the previous alignment.
[0006] While the above-described computerized prosthesis alignment
system is a significant advance in this art, new improvements are
continuously being sought that enhance the ways in which a
prosthesis can be aligned.
SUMMARY
[0007] This summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the Detailed Description. This summary is not intended to identify
key features of the claimed subject matter, nor is it intended to
be used as an aid in determining the scope of the claimed subject
matter.
[0008] The disclosure herein provides a robotic prosthesis
alignment device that may be coupled to the prosthesis sensor
(i.e., transducer) described above that can be controlled by a
computer, including, but not limited to, a wireless personal
digital assistant (PDA) that enables the prosthetist or wearer to
quickly and easily make controlled alignment changes to a
prosthesis. Alternatively, software running on a computer can make
the changes thus, creating an autonomously self-aligning
prosthesis.
[0009] A robotic prosthesis alignment device is disclosed in a
first embodiment, comprising a translation assembly comprising a
first slide deck and a second slide deck that translates in a
different direction to the first slide deck; an angulation assembly
comprising a first wedge and a second wedge, each wedge being
separately capable of rotation; and one or more drivers to move the
first and second slide decks and rotate the first and second
wedges.
[0010] The device of the first embodiment, wherein the translation
assembly provides displacement of an object attached to the
translation assembly along a two dimensional plane.
[0011] The device of the first embodiment, wherein the angulation
assembly provides displacement by tilting an object attached to the
angulation assembly.
[0012] The device of the first embodiment, wherein the movement of
the first and second slide decks is linear.
[0013] The device of the first embodiment, wherein each wedge
comprises a circular member that varies in height around the
circumference.
[0014] The device of the first embodiment, further comprising, a
driver having a revolution counter and, a processor that correlates
a translational position to the number of revolutions.
[0015] The device of the first embodiment, further comprising, a
driver having a revolution counter and, a processor that correlates
an angular position to the number of revolutions.
[0016] The device of the first embodiment, further comprising, a
sensor for each slide deck that measures the position of the slide
deck and, a processor that determines the translational position
from the sensor measurement.
[0017] The device of the first embodiment, further comprising, a
sensor for each wedge that measures the position of the wedge and,
a processor that determines the angular position from the sensor
measurement.
[0018] The features disclosed above can be used singly or in
combination with any other one or more or all features of the
device of the first embodiment.
[0019] A prosthesis system is disclosed in a second embodiment,
comprising a prosthesis socket for receiving an amputated limb; a
prosthesis shank attached to the prosthesis socket; a prosthesis
foot attached to the lower end of the prosthesis shank; and a
robotic prosthesis alignment device of the first embodiment
attached at the joint between the prosthesis socket and the
prosthesis shank and/or at the joint between the prosthesis shank
and the prosthesis foot, the robotic prosthesis alignment device
comprising encoders that provide a translational position and
angular position of the prosthesis.
[0020] The prosthesis of the second embodiment, wherein the robotic
prosthesis device comprises a translation assembly that displaces
the prosthesis socket in relation to the prosthesis foot along a
two dimensional plane.
[0021] The prosthesis of the second embodiment, wherein the robotic
prosthesis device comprises an angulation assembly that tilts the
prosthesis socket in relation to the prosthesis foot.
[0022] The prosthesis of the second embodiment, wherein the robotic
prosthesis device comprises, a driver having a revolution counter
and, a processor that correlates a translational position to the
number of revolutions.
[0023] The prosthesis of the second embodiment, wherein the robotic
prosthesis device comprises, a driver having a revolution counter
and, a processor that correlates an angular position to the number
of revolutions.
[0024] The prosthesis of the second embodiment, comprising a driver
having a revolution counter and a processor that correlates an
angular position to the number of revolutions.
[0025] The prosthesis of the second embodiment, comprising a sensor
that measures the linear position of the translation assembly.
[0026] The prosthesis of the second embodiment, comprising a sensor
that measures the angular position of the angulation assembly.
[0027] The prosthesis of the second embodiment, further comprising
a computer in communication with the robotic prosthesis alignment
device, wherein the computer computes a gait cycle profile from the
translational and angular position.
[0028] The prosthesis of the second embodiment, further comprising
a memory device having stored therein correlations of linear
positions and angular positions to a plurality of gait cycle
profiles.
[0029] The prosthesis of the second embodiment, further comprising
a torque sensor attached to the prosthesis that provides torque
measurements to generate a profile of a gait cycle.
[0030] The prosthesis of the second embodiment, wherein the
computer compares a gait cycle profile generated from translational
and angular positions to a gait cycle stored in a database and,
computes a translational position and angular position that
approximately matches the gait cycle profile stored in the
database.
[0031] The features disclosed above can be used singly or in
combination with any other one or more or all features of the
prosthesis of the second embodiment.
[0032] A method for automatically controlling the alignment of a
prosthesis is disclosed in a third embodiment, comprising measuring
a first translational and angular position of a mechanical joint on
a prosthesis and providing the measurements to a computer;
determining via the computer, a first gait cycle profile from the
first translational and angular position of the mechanical joint;
obtaining via the computer, a second gait cycle profile stored in a
computer memory; comparing via the computer, the first gait cycle
profile to the second gait cycle profile and determining
differences; calculating via the computer, a second translational
position and angular position calculated to reduce the differences
between the first and second gait cycle profiles; and moving the
mechanical joint to the second translational position and angular
position.
[0033] The method of the third embodiment, comprising counting the
revolutions of a driver to determine the translational position of
the mechanical joint.
[0034] The method of the third embodiment, comprising counting the
revolutions of a driver to determine the angular position of the
mechanical joint.
[0035] The method of the third embodiment, comprising
electronically sensing the translational position and angular
position of the mechanical joint.
[0036] The method of the third embodiment, wherein the first gait
cycle profile is determined by searching a database having stored
therein profiles of gait cycles correlating to translational
positions and angular positions.
[0037] The method of the third embodiment, wherein the first gait
cycle profile is determined by torque forces measured along the
posterior/anterior plane and right/left planes.
[0038] The method of the third embodiment, wherein the mechanical
joint attaches a prosthesis socket to a prosthesis shank or a
prosthesis shank to a prosthesis foot.
[0039] The method of the third embodiment, wherein the mechanical
joint comprises a robotic prosthesis alignment device, comprising a
translation assembly comprising a first slide deck and a second
slide deck that translates in a different direction to the first
slide deck; an angulation assembly comprising a first wedge and a
second wedge, each wedge being separately capable of rotation; and
one or more drivers to move the first and second slide decks and
rotate the first and second wedges.
[0040] The features disclosed above can be used singly or in
combination with any other one or more or all features of the
method of the third embodiment.
[0041] A surrogate device for transferring an alignment to a
prosthesis is disclosed in a fourth embodiment, comprising a first
wedge comprising marks, wherein the marks are determinative of a
position on the wedge; a second wedge comprising marks, wherein the
marks are determinative of a position on the wedge, wherein the
first and second wedge are rotationally positionable with respect
to each other such that aligning a mark of the first wedge with a
mark on the second wedge results in a predetermined angular
position.
[0042] The surrogate device disclosed in the fourth embodiment,
wherein each wedge generally defines a first and a second side
tilted at an angle with respect to each, wherein the side of one
wedge is positionable on a side of the other wedge, the combined
heights of the wedges resulting in an angle of tilting.
[0043] The surrogate device disclosed in the fourth embodiment,
wherein the first wedge further comprises interlocking projections
on the side facing the second wedge, and the second wedge comprises
interlocking projections on the side facing the first wedge.
[0044] The surrogate device disclosed in the fourth embodiment,
further comprising a first deck comprising marks and a second deck
comprising marks, wherein the marks are determinative of a position
on the decks, wherein the first and second decks are
translationally positionable with respect to each other such that
aligning a mark of the first deck with a mark on the second deck
results in a predetermined translational position.
[0045] The features disclosed above can be used singly or in
combination with any other one or more or all features of the
surrogate device of the fourth embodiment.
[0046] A method for maintaining the alignment of a prosthesis is
disclosed in a fifth embodiment, comprising setting the angular
alignment of a prosthesis, wherein the angular alignment is
controlled by a robotic device having first and second wedges that
are automatically and rotationally positionable with respect to
each other; moving the wedges with respect to each other to achieve
an alignment; taking a measurement of the positions of the two
wedges in the alignment; assembling a surrogate device having first
and second wedges that are assembled to correlate with the measured
positions of the wedges of the robotic device to achieve an
alignment achieved with the robotic device.
[0047] The method of the fifth embodiment, further comprising
setting the translational alignment of the prosthesis, wherein the
translational alignment is controlled by a robotic device having
first, second and third slide decks that are automatically and
translationally positionable with respect to each other and taking
a measurement of the positions of the slide decks, and assembling
the surrogate device having two decks that are assembled to
correlate with the measured positions of the slide decks of the
robotic device.
[0048] The method of the fifth embodiment, wherein the position of
the wedges is taken by visually viewing the wedges.
[0049] The method of the fifth embodiment, wherein the position of
the wedges is taken by an encoder and computer providing the
positions.
[0050] The method of the fifth embodiment, wherein the position of
the slide decks is taken by visually viewing the slide decks.
[0051] The method of the fifth embodiment, wherein the position of
the slide decks is taken by an encoder and computer providing the
positions.
[0052] The features disclosed above can be used singly or in
combination with any other one or more or all features of the
method of the fifth embodiment.
[0053] This disclosure provides enabling technology for the
difficult implementation of telerehabilitation for patients in
areas without adequate professional coverage.
DESCRIPTION OF THE DRAWINGS
[0054] The foregoing aspects and many of the attendant advantages
of this invention will become more readily appreciated as the same
become better understood by reference to the following detailed
description, when taken in conjunction with the accompanying
drawings, wherein:
[0055] FIG. 1 is a diagrammatical illustration of a prior art
prosthesis;
[0056] FIG. 2 is a diagrammatical illustration of a robotic
prosthesis alignment device coupled to a torque sensor and control
module in accordance with one embodiment of the present
disclosure;
[0057] FIG. 3 is a diagrammatical illustration of an exploded view
of a portion of the robotic prosthesis alignment device in
accordance with one embodiment of the present disclosure;
[0058] FIG. 4 is a diagrammatical illustration of a cut-away view
of a portion of the robotic prosthesis alignment device in
accordance with one embodiment of the present disclosure;
[0059] FIG. 5 is a diagrammatical illustration of an exploded view
of a portion of the robotic prosthesis alignment device in
accordance with one embodiment of the present disclosure;
[0060] FIG. 6 is a diagrammatical illustration of an exploded view
of a portion of the robotic prosthesis alignment device in
accordance with one embodiment of the present disclosure;
[0061] FIG. 7 is a diagrammatical illustration of the robotic
prosthesis alignment device incorporated into a prosthesis
including a prosthesis shank, prosthesis foot, and prosthesis
socket in accordance with one embodiment of the present
disclosure;
[0062] FIG. 8 is a schematic illustration of the control scheme of
a computer device in communication with the robotic prosthesis
alignment device in accordance with one embodiment of the present
disclosure;
[0063] FIG. 9 is a diagrammatical illustration showing a
representative computer used with the robotic prosthesis alignment
device in accordance with one embodiment of the present
disclosure;
[0064] FIG. 10 is a diagrammatical illustration showing a first
operational mode of the robotic prosthesis alignment device in
accordance with one embodiment of the present disclosure;
[0065] FIG. 11 is a diagrammatical illustration showing a second
operational mode of the robotic prosthesis alignment device in
accordance with one embodiment of the present disclosure;
[0066] FIG. 12 is a diagrammatical illustration showing a third
operational mode of the robotic prosthesis alignment device in
accordance with one embodiment of the present disclosure;
[0067] FIG. 13 is a diagrammatical illustration of a graphical user
interface of the first operational mode of the robotic prosthesis
alignment device in accordance with one embodiment of the present
disclosure;
[0068] FIG. 14 is a diagrammatical illustration of a graphical user
interface of the second operational mode of the robotic prosthesis
alignment device in accordance with one embodiment of the present
disclosure;
[0069] FIG. 15 is a diagrammatical illustration of a graphical user
interface of the third operational mode of the robotic prosthesis
alignment device in accordance with one embodiment of the present
disclosure;
[0070] FIG. 16 is a graph showing a representative gait cycle
profile of socket reaction forces along the anterior/posterior
plane and a representative optimal gait cycle profile.
[0071] FIG. 17 is a flow diagram of a method for automatically
performing self-alignment of a prosthesis;
[0072] FIG. 18 is a diagrammatical illustration of an exploded view
of a surrogate device in accordance with one embodiment of the
present disclosure;
[0073] FIG. 19 is a diagrammatical illustration of an exploded view
of a surrogate device in accordance with one embodiment of the
present disclosure; and
[0074] FIG. 20 is a flow diagram of a method of maintaining the
alignment of a prosthesis with the use of a surrogate device.
DETAILED DESCRIPTION
[0075] Referring to FIG. 2, a robotic prosthesis alignment device
101 is disclosed that can be coupled to the torque sensor 100
disclosed in the above-referenced publications to automatically
adjust the translational and angular alignment of a prosthesis.
However, the robotic prosthesis alignment device 101 can be used
without the torque sensor 100. The torque sensor 100 includes an
inverted pyramid adaptor that can be coupled to the top of the
robotic prosthesis alignment device 101. The pyramid adaptor has a
four-sided protuberance that includes four flat sides. Typically,
four set screws 103 are used to set the position of the pyramid
adaptor and thus align the prosthesis. The base of the pyramid
adaptor has a convex surface which rests on a concave surface, thus
allowing articulation and adjustment in the left/right plane and
the front/back plane. Once the proper alignment is determined, the
set screws are tightened against the four-sided protuberance, thus
maintaining the alignment. The robotic prosthesis alignment device
101 disclosed herein allows either a user, prosthetist or a
computer to take control and automatically perform the alignment.
Thus, the set screws 103 may now only be used for a rough alignment
and the robotic prosthesis alignment device provides the fine
alignment. In one embodiment disclosed herein, the pyramid adaptor
can be rigidly mated to the robotic prosthesis alignment device
101. For example, the pyramid adaptor can be attached level to the
top surface of the robotic prosthesis alignment device 101. The
torque sensor 100 disclosed in the prior publications might be
desirable for applications that may require the measurement of
torque forces simultaneously with automatic adjustment. For
example, the torque sensor 100 used in combination with the robotic
prosthesis alignment device 101 can be used to initially obtain a
table or database of gait cycle profiles correlating to specific
lateral and angular positions. Once the database is created, the
robotic prosthesis alignment device 101 can be used without the
torque sensor 100. In the latter embodiments, the robotic
prosthesis alignment device can be adjusted by referencing a
database that correlates a specific lateral and angular position to
a gait profile. For example, the database contains profiles of gait
cycles correlating to every specific lateral position and angular
position that is attainable with the robotic prosthesis alignment
device. In another embodiment, a pyramid adaptor and set screws may
be omitted from the prosthesis and, all alignment can be made using
the robotic prosthesis alignment device 101.
[0076] Referring to FIG. 2, the robotic prosthesis alignment device
101 includes a translation assembly and an angulation assembly.
Translational movement means movement in two directions which can
be orthogonal to each other. Translational movement is movement on
a two-dimensional plane. Translational movement can be measured
with respect to a reference position, for example, a reference
position might be defined as the position when the central axis of
the prosthesis shank is concentric with the central axis of the
pyramid adaptor at the bottom of the prosthesis socket. Angular
movement is movement of an entire plane tilting with respect to a
reference plane, such as the ground plane, or the reference plane
to which the angle of tilting is referenced might be defined when
the central axis of the prosthesis shank is perpendicular to the
plane made by the surface of the pyramid adaptor. However, lateral
and angular movement can be defined in other ways.
[0077] The translation assembly comprises robotic slide decks
including an upper slide deck 104, a middle slide deck 106, and a
lower slide deck 108. Referring to FIGS. 3 and 4, the assembly
comprised of the slide decks 104, 106, and 108 is for translation
in two axes that are orthogonal to each other. The upper slide deck
104 may include the receptacle or coupling for receiving the
pyramid adaptor protuberance that would normally be received by the
top of the prosthesis shank. The middle slide deck 106 is
positioned below the upper slide deck 104. Slide-locking means are
provided at the interface of the upper slide deck 104 and the
middle slide deck 106. The slide-locking means can include a pair
of interlocking rails, one disposed on the lower surface of the
upper slide deck 104 and one disposed on the upper surface of the
middle slide deck 106. In one embodiment, the rails may be
respectively configured similar to an elongated dovetail "mortise
and tenon." The upper slide deck 104 includes a bore 124 within the
tenon component extending the length thereof and having an open
channel for the entire length at a lower section. A translation
screw or worm gear, such as translation screw 131 (FIG. 3) can be
used to move slide deck 104 in relation to slide deck 106. The
translation screw 131 can be rotated manually. Once the desired
translation is achieved, a set screw 133 can be tightened to apply
pressure to the side of the translation screw 131 to prevent the
translation screw 131 from further rotating. Instead of operating
manually, the rotating motion can be provided by an actuator or
driver 117 that rotates translation screw 131. In either the manual
or driven embodiment, the translation screw 131 is engaged to
mating screw slots 137 provided at one end of the mortise component
of the middle slide deck 106. The translation screw 131 is then
able to engage the slots 137 through the open channel in the bottom
of the bore 124. Rotation of the translation screw 131 would then
cause the upper slide deck 104 to slide in relation to the middle
slide deck 106. In another embodiment, as an alternative to the
translation screw, a worm gear, or an Acme screw and nut can be
used. In a still further embodiment, the sliding motion could be
achieved with a "smart" screwdriver that under wireless command
from a PDA, for example, would be used to drive the sliding decks
assembly to the desired position, and then could be detached from
the assembly. Thus, automation and computer control is possible
without the burden of added weight or bulk to the leg. The upper
slide deck 104 includes an index mark 120. The middle slide deck
106 includes a graduated scale 121 on a side thereof. The scale can
be divided according to any non-dimensional or dimensional units,
such as inches or millimeters. Therefore, the amount of travel of
the upper slide deck 104 and middle slide deck 106 can be
determined by visually noting the location of the index mark 120 on
the graduated scale 121 and whether the movement is positive or
negative. Alternatively, the relative position of the slide decks
104 and 106 can be determined by a computer and processor. The
latter can be achieved by receiving input from the driver 117 and
counting the revolutions of the driver that correlate to a certain
position. For example, the driver can be driven in one direction to
the limit of travel, the counter is initialized to zero and each
revolution in the opposite direction can correlate to an increment
of travel. Also, switches and sensors, such as magnetic sensors,
can be used to measure the position of the slide deck travel.
[0078] The lower slide deck 108 is positioned below the middle
slide deck 106. Slide-locking means are provided at the interface
of the middle slide deck 106 and the lower slide deck 108. The
slide-locking means can include a pair of interlocking rails, one
disposed on the lower surface of the middle slide deck 106 and one
disposed on the upper surface of the lower slide deck 108. In one
embodiment, the rails may be respectively configured similar to an
elongated dovetail "mortise and tenon." The rails at the interface
between the middle slide deck 106 and the lower slide deck 108 are
placed perpendicular to the rails at the interface of the middle
slide deck 106 and the upper slide deck 104. The middle slide deck
106 includes a bore 122 within the tenon component extending the
length thereof and having an open channel 123 for the entire length
at a lower section. A translation screw or worm gear, such as
translation screw 130 (FIG. 3) can be used to move slide deck 106
in relation to slide deck 108. The translation screw 130 can be
rotated manually. Once the desired translation is achieved, a set
screw 135 can be tightened to apply pressure to the side of the
translation screw 130 to prevent the translation screw from further
rotating. Instead of operating manually, the rotating motion can be
provided by an actuator or driver 119 that rotates translation
screw 130. In either the manual or driven embodiment, the
translation screw 130 is engaged to mating screw slots 139 provided
at one end of the mortise component of the lower slide deck 108.
The translation screw 130 is then able to engage the slots 139
through the open channel 123 in the bottom of the bore 122.
Rotation of the translation screw 130 would then cause the middle
slide deck 106 to slide in relation to the lower slide deck 108. In
another embodiment, as an alternative to the translation screw, a
worm gear, or an Acme screw and nut can be used. In a still further
embodiment, the sliding motion could be achieved with a "smart"
screwdriver that under wireless command from a PDA, for example,
would be used to drive the sliding decks assembly to the desired
position, and then could be detached from the assembly. Thus,
automation and computer control is possible without the burden of
added weight or bulk to the leg. The middle slide deck 106 includes
an index mark 128. The lower slide deck 108 includes a graduated
scale 126 on a side thereof. The scale can be divided according to
any non-dimensional or dimensional units, such as inches or
millimeters. Therefore, the amount of travel of the middle slide
deck 106 and lower slide deck 108 can be determined by visually
noting the location of the index mark 128 on the graduated scale
126 and whether the movement is positive or negative.
Alternatively, the position of the slide decks 106 and 108 can be
determined by a computer and processor. The latter can be achieved
by receiving input from the driver 119 and counting the revolutions
of the driver that correlate to a certain position. For example,
the driver can be driven in one direction to the limit of travel,
the counter is initialized to zero and each revolution in the
opposite direction can correlate to an increment of travel. Also,
switches and sensors, such as magnetic sensors, can be used to
measure the position of the slide deck travel.
[0079] Accordingly, by the use of the three slide deck components
104, 106, and 108, it is possible to translate the pyramid adaptor,
and thus, the prosthesis socket 60 attached to the robotic
prosthesis alignment device 101, to any coordinates in a
two-dimensional or horizontal plane; thus, being able to adjust the
lateral position of the prosthesis socket 60 in relation to the
position of the prosthesis shank 30 and foot 20.
[0080] Referring to FIGS. 2, 4, and 5, the robotic prosthetic
alignment device 101 further includes first 110 and second 112
angulation decks comprising the angulation assembly. Each
angulation deck includes a housing 113, 115, respectively, within
which a worm gear is provided on a side thereof, the worm gears
being supported by appropriate bearings in the housing. The worm
gears 143, 141 are turned by drivers 114 and 116, respectively.
Each housing further supports a robotic wedge 140 and 142 generally
placed in the center thereof and adapted to rotate within the
housing. The housing 113 of the upper angulation deck 110 has the
wedge 142 supported on the lower slide of the housing 113, and the
housing 115 of the lower angulation deck 112 has the wedge 140
supported on the upper side of the housing 115. As best seen in
FIG. 5, the wedges 142, 140 are circular. Each wedge may be viewed
as defining an upper side plane and a lower side plane, wherein the
planes are angled with respect to each other. The upper side plane
is separated from the lower side plane, thus, each wedge may be
viewed as having a low point (or small height dimension) on one
side thereof and a high point (or large height dimension) on the
opposite side thereof. When placed on top of the other, the sum of
the wedge height dimensions is cumulative and the individual wedge
angles may increase the combined angle if the two high points and
low points are aligned or the angles may cancel each other when the
high point of one wedge is aligned with the low point of the other
wedge, effectively resulting in no angle or an angle of 0.degree..
Thus, the use of the pair wedges 140, 142 may be used to tilt a
plane at any angle from 0.degree. to the maximum angle when both
high points are aligned. Further, because both circular wedges
rotate, it is possible to effect such an angular position at any
point of 360.degree. of rotation. To enable rotation, each wedge
140, 142 has toothed gears around the circumference that mesh with
the respective worm gear 141, 143. Each worm gear is driven by a
driver. The driver 114 can rotate worm gear 143 and the driver 116
can rotate worm gear 141. Driver 114 is supported by motor mount
155 to the housing 113 and motor mount 157 supports driver 116 to
the housing 115. Similar to drivers 117, 119 of the translation
assembly, drivers 114 and 116 can include revolution counters that
through the use of a computer and processor can measure the
position of one wedge in relation to the other wedge. Each
revolution can then correlate to an angle of tilting and to a
position with respect to any degree of rotation to measure
precisely how much angular adjustment and its direction at any
time. For example, a revolution of zero may be assigned to both
drivers 114, 116 when the wedges 140 and 142 are aligned such that
the high point of one wedge is aligned to a low point of the other
wedge, resulting in the minimum angle of tilt possible. For each
revolution or number of revolutions of each driver 114, 116, the
resulting angle can be recorded and a database can be generated of
the angle, the position with respect to the front to back and side
to side planes, and the revolutions of each driver 114, 116. Thus,
to arrive at a certain angle of tilting of the prosthesis, the
drivers 114, 116 can be commanded to a certain revolution.
Alternatively to counting revolutions, sensors can be used to
determine the position of one wedge with respect to the other. To
further enable rotation of the wedges 140, 142, a turntable bearing
151 is provided between the interface of the lower surface of the
upper wedge 142 and the upper surface of the lower wedge 140. The
upper surface of the upper wedge 142 is further in contact with the
bottom surface of the housing 113 via a second turntable bearing
153. The lower surface of the lower wedge 140 is further in contact
with the upper surface of the housing 115 via a third turntable
bearing 149. Accordingly, both the lower wedge 140 and the upper
wedge 142 are permitted to rotate independently within their
respective housing 115, 113 without causing rotation of the pyramid
adaptor on top and tube clamp adaptor 40 below. As mentioned
before, each angulation deck 110, 112 includes a worm gear that is
coupled to a toothed gear provided around the circumference of each
of the wedges. As the drivers rotate one or both of the wedges, the
angle of tilting and its direction can be controlled. Combining
different positions of the wedges 140, 142 varies the side-to-side
angle and the front-to-back angle. Both the upper 142 and the lower
140 wedges may include a graduated scale along the periphery so
that the position of one wedge with respect to the other can be
visually read. A surrogate device, as further discussed below, can
have wedges 1402, 1404 that tilt when rotated similar to the wedges
140, 142, and can be used to transfer the angular alignment. These
surrogate wedges 1402, 1404 can have a graduated scale similar to
the scale used in the wedges 140, 142. Using the reading obtained
from the wedges 140, 142, the numerals on the scales of the
surrogate wedges can be configured to line up similarly thus
producing a similar alignment to the robotic prosthesis alignment
device 101. Any non-dimensional or dimensional units, such as
degrees, can be used to measure the location of one wedge with
respect to the other and with respect to the housings.
Alternatively, the position of the wedge rings may be determined
via a computer and processor. The latter may be accomplished by
counting the revolutions of the drivers 114 and 116 and correlating
specific combinations of revolutions of each driver to a degree of
tilting and to its direction. Alternatively sensors, such as a
magnetic sensors can be used to measure the position of the two
wedges. Alternatively to having graduated scale on the wedges 140,
142, the computer may provide a dimensionless number or numbers
that defines the position of the wedge 140 to the position of the
wedge 142. These numbers provided by the computer can then be used
to align to surrogate wedges 1402, 1404.
[0081] Because the wedges cause tilting during rotation, the
translation assembly which is positioned on the top of the upper
angulation deck 110 is tilted along with the angulation assembly.
To that end, and referring to FIG. 6, the bottom slide deck 108 of
the translation assembly is connected via a universal joint 160 to
the tube clamp adaptor 40. As shown in FIG. 5, the housings 113,
115, the wedges 140, 142, and the bearings 149, 151, 153, all have
center bores allowing the passage of the universal joint
therethrough.
[0082] Referring to FIG. 7, the robotic prosthesis alignment device
101 is shown incorporated into a prosthesis to connect the
prosthesis socket 60 to the prosthesis tube clamp adaptor 40. While
FIG. 7 shows the torque sensor 100 and module 102 also attached to
the prosthesis, it is not necessary to use the torque sensor 100
and module 102 simultaneously with the robotic prosthesis alignment
device 101. Further, although the robotic prosthesis alignment
device 101 is shown at the joint between the prosthesis socket 60
and prosthesis shank 30, the robotic prosthesis alignment device
101, as well as the torque sensor 100 and module 102, can also be
located at the joint between the prosthesis shank 30 and the
prosthesis foot 20, as well as having two robotic prosthesis
alignment devices, one at the joint between the socket and shank
and the other at the joint between the shank and foot. Placing the
robotic prosthesis alignment device 101 at the joint between foot
20 and shank 30 might be desirable because small angular movements
are not magnified by the length of the shank 30.
[0083] Referring to FIG. 8, a schematic block diagram of the
robotic prosthesis alignment device's 101 electronic connections is
illustrated. As a point of reference FIGS. 7 and 8 of the prior
publications schematically illustrate the electronics of the torque
sensor 100 and module 102 and will not be illustrated herein for
brevity. The computer disclosed in the prior publications or a
different computer 300 can be communicatively coupled to the torque
sensor 100 and module 102, and further capable of running
prosthesis alignment software as disclosed in the referenced
publications, as well as also communicating with the robotic
prosthesis alignment device 101 disclosed herein. The computer
device 300 can be a handheld computer, such as a PDA, and is used
to provide the motor control logic 302 that drives the individual
drivers 114, 116, 117 and 119 that determine the setting of the
transverse sliding decks and also to set the angle using the
angulation decks. Alternatively, the computer device 300 may also
be an embedded processor. The drivers 114, 116, 117, 119 are
communicatively coupled to encoders that are further coupled to the
computer 300. The motor control logic 302 uses hardware that takes
position data from the encoders, compares the current position
using software running on computer 300 against the position goal
from the computer 300 software and drives the motors until the
position goal and encoder outputs match. The computer 300 may be a
personal digital assistant (PDA) and may have wireless transmission
capability, such as Bluetooth.RTM.. The PDA can transmit
instructions to the robotic prosthesis alignment device 101 to tilt
the prosthesis socket in one or both planes and to translate the
prosthesis socket in orthogonal directions. The computer 300
software, such as running on a PDA, can make decisions and run
significant algorithms relating to the translation and rotation of
the translating decks and wedges.
[0084] The applications running the robotic prosthesis alignment
device 101 may be described in the context of computer-executable
instructions, such as program modules being executed by the host
computer 300. The computer-executable instructions or applications
may be stored on one or more computer readable medium, such as, but
not limited to hard drives, memory, disks, and the like. Generally
described, program modules include routines, programs,
applications, objects, components, data structures and the like,
that perform tasks or implement particular abstract data types. The
following description provides a general overview of the computer
300 with which the method for automatically aligning a prosthesis
may be implemented. Then, the method for automatically aligning the
prosthesis will be described, including the use of applications on
the computer. The illustrative examples provided herein are not
intended to be exhaustive or to limit the invention to the precise
forms disclosed. Similarly, any steps described herein may be
interchangeable with other steps or a combination of steps or, be
arranged in a different sequence in order to achieve the same
result.
[0085] FIG. 9 illustrates an exemplary host computer 300 with
components that are capable of implementing an automatic method to
align a prosthesis by conducting "gait analysis". The gait analysis
application 316 and the phase and step detection application 317
have been illustrated and disclosed in the prior publications and
will not be described herein for brevity. The gait analysis
application 316 and the phase and step detection application 317
can be used to generate a database 315 of profiles of gait cycles
correlating to each lateral position and each angular position
attainable with the robotic prosthesis alignment device 101.
However, once the database 315 is created, a user of the robotic
prosthesis alignment device 101 need not use the gait analysis
application 316 and the phase and step detection application 317
for automatically performing self-alignment of the prosthesis as
further disclosed below.
[0086] Those skilled in the art and others will recognize that the
host computer 300 may be any one of a variety of devices including,
but not limited to, personal computing devices, server-based
computing devices, mini and mainframe computers, laptops, or other
electronic devices having some type of memory. The host computer
300 can also be an embedded processor located on the robotic
prosthesis alignment device 101. The host computer 300 depicted in
FIG. 12 includes a processor 302, a memory 304, a computer-readable
medium drive 308 (e.g., disk drive, a hard drive, CD-ROM/DVD-ROM,
etc.), that are all communicatively connected to each other by a
communication bus 310. The memory 304 generally comprises Random
Access Memory ("RAM"), Read-Only Memory ("ROM"), flash memory, and
the like.
[0087] As illustrated in FIG. 9, the memory 304 stores an operating
system 312 for controlling the general operation of the host
computer 300. The operating system 312 may be a special purpose
operating system designed for the computerized prosthesis alignment
system 100. Alternatively, the operating system 312 may be a
general purpose operating system, such as a Microsoft.RTM.
operating system, a Linux operating system, or a UNIX.RTM.
operating system. In any event, those skilled in the art and others
will recognize that the operating system 312 controls the operation
of the host computer 300 by, among other things, managing access to
the hardware resources and input devices. For example, the
operating system 312 performs functions that allow a program to
receive data wirelessly over a radio receiver and/or read data from
the computer-readable media drive 308. As described in further
detail below, moment and axial load data in real time may be made
available to the host computer 300 from the master unit module 102
and from the computer-readable medium drive 308. In this regard, a
program installed on the host computer 300 may interact with the
operating system 312 to process the data received from one or both
the master unit module 102 and the computer-readable media drive
308.
[0088] As further depicted in FIG. 9, the memory 304 additionally
stores program code in the form of applications. The gait analysis
application 316 includes computer-executable instructions that,
when executed by the processor 302, applies an algorithm to
receive, display, and process input, including moment and axial
load data. The gait analysis application 316, among other things,
applies an algorithm to a set of moment data to correct for any
horizontal rotational deviation of the torque sensor 100 during
walking to the actual line of progression and then compares the
corrected data to an optimal model of alignment stored on a device
318. The step and phase detection application 317 applies an
algorithm to a set of moment and axial data to determine if the
prosthesis is being used in steady state walking, and if it is, the
algorithm differentiates each step on the prosthesis and extracts
the moment data beginning each step at initial contact and ending
each step at the following initial contact in the gait cycle.
Further, the step and phase detection application 317 establishes
if the prosthesis is either in stance or swing phase of a gait
cycle at each data point extracted for each step. The gait analysis
application 316 and the phase and step detection application 317
have been illustrated and disclosed in the prior publications and
these applications may be implemented by the host computer 300
disclosed herein or by a different computer to generate that
database 315 mentioned above. Self or automatic alignment is a goal
of methods disclosed herein. The self-aligning automatic alignment
application 319 performs a set of operations, without the use of
the torque sensor 100 and module 102 that can automatically align
the prosthesis with the use of the drivers. The application 319 is
described in association with the flow diagram of FIG. 17
below.
[0089] Referring to FIGS. 10, 11, and 12, the computer 300 may
operate in one of three modes. A first mode (FIG. 10) is for the
robotic prosthesis alignment device 101 to interface with a
prosthetist 801 with the use of a computer 300, a second mode (FIG.
11) is for the user 803 to interface with the robotic prosthesis
alignment device 101 with the computer 300, and the third mode
(FIG. 12) is for the robotic prosthesis alignment device 101 to
interface automatically with a computer, such as computer 300,
either with user interface or without user interface, such as in a
self-aligning automatic mode.
[0090] FIG. 13 is an illustration of a representative graphical
user interface 1101 for the first mode. The interface 1101 includes
buttons 1102 used for selecting between prosthetist, user, and the
computerized prosthesis alignment system. In FIG. 13, the
prosthetist button is highlighted, indicating that the graphical
user interface is customized for a prosthetist. The graphical user
interface 1101 presents to the prosthetist, a figure illustrating
both a side view and a front or back view of the prosthesis,
including the socket, the robotic prosthesis alignment device 101,
and the shank and foot. Referring to the left side of the figure,
in the side view, the prosthetist is able to view the forward or
backwards translation and also the front/back angle. The
prosthetist is presented with a minus button 1104 and a plus button
1106 for adjusting the pitch angle or the front to back angle.
Selecting the minus button 1104 decreases the angle. Alternatively,
selecting the plus button 1106 will increase the angle. The
prosthetist is presented with a minus button 1108 and a plus button
1110 for adjusting the forwards and backwards translation.
Selecting the minus button 1108 decreases the distance that the
shank with foot translates backwards. Alternatively, selecting the
plus button 1110 increases the distance that the shank with foot
translates forwards. When the prosthetist is satisfied with the
settings, the prosthetist can select a DO IT button 1112, and the
changes are executed by the robotic prosthesis alignment device
101. Referring to the right side of the figure, in the front or
back view, the prosthetist is able to view the side-to-side
translation and also the roll angle or the side to side angle. The
prosthetist is presented with a minus button 1114 and a plus button
1116 for adjusting the angle. Selecting the minus button 1114
decreases the angle. Alternatively, selecting the plus button 1116
will increase the angle. The prosthetist is presented with a minus
button 1118 and a plus button 1120 for adjusting the side
translation. Selecting the minus button 1118 will decrease the
distance that the shank with foot will translate medially (towards
the middle of the body). Alternatively, selecting the plus button
1120 will increase the distance that the shank with foot will
translate laterally (towards the outside of the body). When the
prosthetist is satisfied with the settings, the prosthetist can
select the DO IT button 1112, and the changes are executed by the
robotic prosthesis alignment device 101. The graphical user
interface 1101 also presents to the prosthetist choices for the
responsiveness of movements. The user is presented with a fast
1122, normal 1124 and fine tune 1126 button to select
responsiveness from the robotic prosthesis alignment device 101.
The graphical user interface 1101 may present a prior alignment
button 1128. By selecting the prior alignment button 1128, the
computer supporting the graphical user interface recalls from
memory the immediate prior alignment. The graphical user interface
1101 may present a Reset to Neutral button 1129. By selecting the
Reset to Neutral button 1129, the robotic prosthesis alignment
device may return all alignments to the home or neutral
position.
[0091] FIG. 14 is an illustration of a representative graphical
user interface 1230 for the second mode for a user, i.e., the
wearer, of the prosthesis. The graphical user interface 1230 may
present to the user a sensation-oriented interface. In this mode,
the graphical user interface will prompt the user regarding their
sensations during walking, such as whether the user feels their
knee was being pushed in a certain direction as they stepped on the
prosthesis. In one embodiment, the graphical user interface 1230
presents to the user a series of questions concerning the
sensations that the user is experiencing to which the user can
reply by selecting a minus button 1232 or a plus button 1234. For
instance, one example of a question presented to a user may read,
"At the end of the step on my prosthesis . . . ?" And the response
can be a selection of two options; "my knee is falling forward.
There is inadequate support at the end of the step" or, "my knee is
being pushed back. There is resistance to walking forward." By
selecting the negative button 1232 or the plus button 1234, the
user can select which of the two options most closely matches the
sensation being felt. Selecting the plus button 1234 moves the
pointer 1236 in the direction of the second sensation, while
selecting the minus button 1232 moves the pointer 1236 in the
direction of the first sensation. The range of the pointer might
coincide with the range of available adjustment, i.e., either the
translational or angular adjustment or both. In this manner, the
user provides a response that correlates most closely to the actual
sensation being experienced by the user. When the changes have been
entered, the user may select the DO IT button 1112 and the changes
are executed by the robotic prosthesis alignment device 101.
[0092] FIG. 15 is an illustration of a graphical user interface
1350 for the third mode when the computer 300 operates the robotic
prosthesis alignment device 101. The graphical user interface 1350
may present a setup page. In the setup page, the graphical user
interface 1350 may present a Sensor Mounting button 1352, a Sensor
Initialization button 1354, and a Line of Progression button 1356.
These operations have been disclosed in the referenced
publications. The graphical user interface 1350 may perform the
alignment method as disclosed in the above-referenced applications
by selection of the Analyze button 1360. This alignment method uses
the gait analysis application 316 and the step and phase detection
application 317 already disclosed in the referenced publications.
However, in the present disclosed graphical user interface 1350
herein, instead of presenting the user or prosthetist with
instructions on turning the set screws, the graphical user
interface 1350 may present a suggestion 1358, such as degrees of
plantarflexion, dorsiflexion, inversion, eversion and/or distance
of translation in either the lateral or medial direction. By
selecting the DO IT button 1112, the suggestion is executed by the
robotic prosthesis alignment device 101. Furthermore, the
suggestions generated by the disclosed method can be implemented
automatically to provide a self-aligning prosthesis. A
self-aligning prosthesis will not depend on the person to execute
the movement to align the prosthesis, but will automatically move
the prosthesis to the selected alignment. The self-aligning
prosthesis option can be turned off by the user if desired. The
method disclosed herein for providing suggestions that are executed
by the person or automatically is described in association with
FIG. 17 below.
[0093] Before discussing the self-aligning method, a profile of a
gait cycle is briefly described with reference to FIG. 16. A
representative profile of a gait cycle is shown as curve 1601 in
the anterior/posterior socket reaction graph. The right/left socket
reaction graph may also be prepared for a gait cycle. A gait cycle
profile represents a repeating unit of the walking motion, for
example, from initial contact (IC) of the heel of one foot to the
subsequent initial contact of the heel of the same foot. The gait
cycle of one foot includes a stance phase when the foot is in
contact with the ground. The gait cycle includes a swing phase when
the foot is not in contact with the ground. Initial contact is the
start of the stance phase when the heel makes contact with the
ground. Toe-off (TO) is the end of the stance phase when the toe
leaves the ground. The swing phase occurs after toe-off and before
initial contact of the heel. One swing phase and one stance phase
complete a gait cycle. There are torques associated with each gait
cycle along the posterior to anterior and right to left. These
torques can be measured by the torque sensor 100 disclosed in the
prior publications. From these readings a gait cycle profile can be
generated for anterior/posterior socket reaction forces and for
right/left socket reaction forces plotted against the stance phase
from initial contact to toe-off. A theoretical optimum gait cycle
profile is disclosed in the prior publications. This optimum gait
cycle profile is represented by curve 1602.
[0094] Referring to FIG. 17, a method for automatically controlling
the alignment of a prosthesis is schematically illustrated. FIG. 17
is a method that can automatically perform self-alignment of the
prosthesis. The method starts at block 1700. From block 1700, the
method enters block 1702. Block 1702 is for measuring the
translational and/or angular positions of the current prosthesis
alignment. For example, the translation assembly and the angulation
assembly disclosed above may include various ways of determining
the position by encoders, such as by counting the revolutions of a
driver that moves a gear of either the translation assembly or the
angulation assembly. In addition, a sensor may be mounted in a
position on the translation assembly or the angulation assembly
that provides a current position. From block 1702, the method
enters block 1704. In block 1704, a current gait cycle is obtained.
For example, the gait cycle can be obtained from the transducer 100
measuring torque forces and producing a real-time gait cycle using
the gait analysis application 316 and the phase and step detection
application 317. Alternatively, the database 315 of FIG. 9 can be
accessed. The database 317 can contain a look-up table that
correlates translational positions and angular positions to
specific gait cycles. For example, the table can be generated
beforehand, such as by moving the translation assembly throughout
its range in both the two orthogonal directions and obtaining a
profile of a gait cycle at each incremental adjustment while the
angular adjustment is held constant. Once all the possible
combinations of translations in two directions are determined for
one angular position, the angular position can be changed one
increment, and the range of translations is performed, until all
possible translation and angular positions are tested. The profiles
of gait cycles correlating to a specific angulation position can
also be prepopulated in the database. For example, a gait cycle can
be measured using the torque sensor for each incremental adjustment
of a wedge. In the end, a database that has a profile of a gait
cycle correlating to every translational position at every possible
angle can be created. From step 1704, the method enters step 1708.
In step 1708, an optimal profile of a gait cycle can be obtained.
For example, the optimal gait cycle profile can be obtained from a
database 318 (FIG. 9). The optimal gait cycle is calculated from
the equations and methods disclosed in the prior publications.
[0095] From step 1708, the method enters step 1712. In step 1712,
the current gait cycle is compared to the optimal gait cycle and a
difference is determined that is defined as the misalignment.
Various mathematical algorithms can be used to compare one plot of
a gait cycle against another.
[0096] One embodiment for calculating the difference or
misalignment between the current alignment and the optimal
alignment may be to compare one or more of the gait variables
against the alignment model calculated from a larger database of
gait variables collected from multiple and different patients from
numerous prior sessions and stored in the device of the host
computer 300. To analyze for the misalignment, certain "gait"
variables are calculated for a step. Gait variables may include,
but are not limited to some or all of, the anterior/posterior
moment and right/left moment at each 20 percent increment in time
of the stance phase from 0% to 100%; the maxima and minima of the
anterior/posterior moment and right/left moment for the first and
the last 50% of the stance phase; the slope of the change in
anterior/posterior moment and right/left moment during each
successive 20% time increment; and the integrated
anterior/posterior moment and right/left moment measured over the
period of each stance phase. The gait variables are then applied to
a predefined model of alignment. The equations used in deriving the
model of alignment are derived heuristically to minimize an
external criterion called the Prediction Error Sum of Squares, or
PESS, for previously measured socket reaction moments and axial
force with a known set of geometric misalignments.
PESS = 1 N t = 1 N ( y t - f ( x t , a ^ t ) ) t ##EQU00001##
[0097] Where N is the number of gait variable samples available, y
is the target geometric misalignment, and a is an estimation of the
combined parameters that describe the misalignment. The equation
derivations are achieved using the Group Method of Data Handling
described by Madala and Ivakhnenko (Madala, H., and Ivakhnenko, A.,
"Inductive Learning Algorithms for Complex Systems Modeling," CRC
Press, Boca Raton, Fla., USA, 1994). Solving the derived model
equations with the gait variables calculated from the computerized
prosthesis alignment system 100 data, results in a numeric
estimation of the geometric misalignment in the prosthesis
measured. For robustness, estimations from each of the equations
becomes a vote added to a more generalized estimation of the
misalignment.
[0098] From step 1712, the method enters step 1714. In step 1714, a
determination is made as to whether the current gait cycle is
acceptable in comparison to the optimal gait cycle. In block 1714,
checking whether the alignment is okay might compare the current
gate cycle to the optimal gate cycle and if the difference between
the current gait cycle to the optimal gait cycle is below a
threshold limit, the current gait cycle is identified as being
acceptably close to the optimal gait cycle and the alignment is
acceptable. If the determination is "yes," the method enters block
1716 and the alignment is complete, thus terminating the method. If
the determination in block 1714 is "no," the method enters block
1720. In block 1720, the method selects a new transitional and/or
angular position to match the optimal gait cycle. To select a new
transitional and/or angular position to match the optimal gait
cycle, the method can search the database 315 for a gait cycle that
matches or approximates the optimal gait cycle. When the gait cycle
is found, the look-up table will provide the translational
coordinates and the angular coordinates that are correlated to the
gait cycle. For example, this can be provided in the form of a
number of driver revolutions corresponding to certain lateral and
angular positions and/or to a voltage or resistance of a particular
sensor corresponding to certain lateral and angular positions. Once
the lateral and angular positions are know, these can be provided
in the form of a suggestion 1358 as shown in FIG. 15 or the method
can simply move the prosthesis automatically with the use of
drivers without further input. From block 1720, the method enters
block 1722. In block 1722, the computer 300 provides instructions
to move the translation and angulation assemblies to the new
positions. At this point, the method can terminate, thus assuming
that the new positions will provide the closest match to the
optimal gait cycle profile. Alternatively, the method can return to
block 1702 and re-measure the translational and angular positions
for verification and the method runs through steps 1704, 1708,
1712, and 1714 again to test whether the new position is in fact
resulting in the desired optimal alignment.
[0099] Once an optimal alignment is achieved by any of the three
modes, the robotic prosthesis alignment device 101 may need to be
removed from the prosthesis along with the torque sensor 100.
However, removal of the torque sensor 100 and the robotic
prosthesis alignment device 101 should preferably be accomplished
without losing the optimal alignment. To do this as disclosed in
the prior publications, a substitute pyramid adaptor was used that
had the same physical dimensions as the torque sensor. Two set
screws were removed, which left two set screws in the optimal
alignment position. With two set screws removed, the torque
sensor/pyramid adaptor could be disassembled from the prosthesis.
Thereafter, the substitute pyramid adaptor could be substituted for
the torque sensor without losing the alignment. However, a drawback
with this method is that the alignment cannot be transferred to a
different prosthesis. Disclosed herein is a surrogate device that
can be used to achieve the same alignment after the robotic
prosthesis alignment device 101 is removed from the prosthesis. As
disclosed herein, the robotic prosthesis alignment device 101
calculates the angular and translational positions and these can be
provided as numerical indexes, either by visually inspecting the
device once alignment is reached or the computer 300 may provide
the angle and translation positions in units or numbers. The
numerical indexes can be provided visually by viewing the positions
of the translation and angulation assemblies via a index mark and a
graduated scale or can be provided by computations performed by the
computer 300 and displayed on a graphical user interface, such as
shown in the suggestion box 1358 of FIG. 15. The numerical indexes
then provide a means for transferring the alignment with the use of
a surrogate device after the robotic prosthesis device 101 has been
removed. The surrogate device is an intermediate component that
connects that prosthesis shank to the prosthesis socket. The
surrogate device is designed to duplicate the range of alignment
that is achieved with the robotic prosthesis alignment device 101
and can directly replace the geometry of the robotic prosthesis
alignment device 101.
[0100] Referring to FIG. 18, the surrogate device includes a
modified tube clamp adaptor 1400, a first wedge 1402 and second
1404 wedge, and a top coupling plate 1406. The wedge rings 1402 and
1404 can be color coded and made by injection molding a ultrahigh
molecular weight polyethylene or a similarly appropriate resin. The
tube clamp adaptor 1400 includes an upper surface designed to mate
to the bottom surface of the wedge ring 1404. The tube clamp
adaptor 1400 can be attached to the prosthesis shank. Each of the
wedge rings 1402, 1404 includes a graduated scale 1411 along the
circumference. The wedge rings 1402, 1404 have a low point and a
high point that is directly opposite from the low point. One major
surface of each wedge ring 1402, 1404 includes interlocking
features. When assembled, the interlocking surfaces of the wedges
1402, 1404 are positioned against each other. The robotic
prosthesis alignment device 101 includes wedges that could rotate
in relation to one another to set the angular adjustment of the
prosthesis. The wedges of the robotic prosthesis alignment device
101 may include indices on the circumference of the wedge rings
that coincide with the indices of the wedges 1402, 1404 of the
surrogate. In this manner, once alignment is completed, the indices
are visually read from the robotic prosthesis alignment device 101
directly from the wedges 140 and 142 and then, the surrogate wedges
1402, 1404 are aligned so that the indices of the surrogate wedges
1402, 1404 are in the same alignment as the wedges 140, 142 to
duplicate the angular adjustment. In another embodiment, the
computer 300 includes software that can calculate the dimensionless
indices to be used in the surrogate that match the angular
alignment deemed to be optimal. For example, degrees of angular
adjustment can be correlated to a numerical scale. As an example,
an alignment of 3.degree. inversion of the foot coupled by
2.5.degree. plantarflexion may be duplicated by orienting the two
interlocking wedge rings 1402 and 1404 so that the number 13 on the
white ring is matched to the number 15 on the red ring. The
interlocking teeth in the two rings maintain the alignment while
the user tightens a clamping bolt. The tube clamp adaptor 1400
surface includes an index pin 1408 that fits into a slot in the
lower surface of the wedge ring 1404. The wedge ring 1404 includes
an index mark 1410 on the circumference of the ring that can be the
high point in the ring, and which is aligned to the index mark 1410
on the tube clamp adaptor 1400. The surrogate includes a top
coupling plate 1406. The top coupling plate 1406 is used to attach
the surrogate to the base of the prosthesis socket.
[0101] Referring to FIG. 19, the surrogate device may also include
a horizontal component. The horizontal component would be used in a
prosthesis, if horizontal translation was used in alignment.
Otherwise, a simple spacer may be added to the surrogate to achieve
correct length, i.e., height. The horizontal component of the
surrogate includes an upper surrogate deck 1502 and lower surrogate
deck 1504. The upper surface of the lower deck 1504 and the lower
surface of the upper deck 1502 include locking features. The
surfaces having the locking features are placed in contact with
each other. The lower deck 1504 includes a slot that has a length
greater than the width. The upper deck 1502 includes a slot that
has a length greater than the width. In use, the lower deck 1504
and the upper deck 1502 will be placed so that the respective slots
are perpendicular to one another. The lower deck 1504 includes an
index mark 1506 on one side of the deck 1504 and a graduated scale
1508 on the adjacent side. The upper deck 1502 includes an index
mark 1510 on one side of the deck and a graduated scale 1512 on the
adjacent side. The scales 1508 and 1512 are dimensionally similar
to the scales 121, 126 used on the middle 106 and lower 108 slide
decks to be able to directly transfer the alignment to the
surrogate. As disclosed herein, the robotic prosthesis alignment
device 101 includes a first, second, and third deck in a stacked
arrangement. As also disclosed, the upper deck 104 includes an
index mark 120, the middle deck 106 includes a graduated scale 121
and an index mark 128, and the lowest deck 108 includes a graduated
scale 126. Therefore, with the use of the robotic prosthesis
alignment device 101, the translation can be visually read directly
from the scales of the middle 106 and lower 108 decks. These
readings can then be transferred directly to the upper 1502 and the
lower 1504 decks of the surrogate to maintain the same translation
that was achieved with the use of the robotic prosthesis alignment
device 101. In the horizontal component of the surrogate, the top
deck 1502 alignment rotation is located by the four-bolt attachment
to the prosthesis socket, while the prosthesis shank is located by
marking the shank at the slot of the tube clamp of the actuator,
then matching the mark on the shank to the slot in the surrogate
tube clamp.
[0102] FIG. 20 discloses the method of performing the transfer of
the translational and angular alignment from the robotic prosthesis
alignment device 101 to the surrogate device. The method starts at
start block 2000. From start block 2000, the method enters block
2002. In block 2002, the method uses the robotic prosthesis
alignment device to translationally and angularly align the
prosthesis in accordance with the method described in association
with FIG. 17 using the robotic wedges 140, 142 and the robotic
slide decks 104, 106 and 108. When alignment is completed, the
method enters block 2004. In block 2004, the positions of the
robotic wedges 140, 142 and of the robotic slide decks 104, 106 and
108 are read, either visually or through the use of a computer 300
and software that will provide a position or numerical index
denoting the translational and angular positions of the robotic
wedges 140, 142 and the robotic slide decks 104, 106, and 108. From
block 2004, the method enters block 2006. In block 2006, the method
relies on a user or prosthetist to construct a surrogate device
using the surrogate wedges 1402 and 1404 and/or the surrogate decks
1502 and 1504. The surrogate is constructed such that the surrogate
wedges 1402 and 1404 are placed in a manner to duplicate the
angular alignment achieved using the robotic wedges 140, 142 and
the surrogate decks 1502 and 1504 are placed in a manner to
duplicate the translational alignment using the robotic slide decks
104, 106 and 108. When constructed in such manner, the surrogate
device can replace the robotic prosthesis alignment device 101 in
the same or different prosthesis. The advantage being that the
alignment is not lost and can be retained with the use of a
surrogate device.
[0103] While illustrative embodiments have been illustrated and
described, it will be appreciated that various changes can be made
therein without departing from the spirit and scope of the
invention.
* * * * *