U.S. patent application number 16/421780 was filed with the patent office on 2020-11-26 for actuator-based exercise and training device.
The applicant listed for this patent is Tyson Cobb, Travis Craig, Jeremy Gines, Peter Neuhaus. Invention is credited to Tyson Cobb, Travis Craig, Jeremy Gines, Peter Neuhaus.
Application Number | 20200368581 16/421780 |
Document ID | / |
Family ID | 1000005207281 |
Filed Date | 2020-11-26 |
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United States Patent
Application |
20200368581 |
Kind Code |
A1 |
Cobb; Tyson ; et
al. |
November 26, 2020 |
ACTUATOR-BASED EXERCISE AND TRAINING DEVICE
Abstract
An exercise device where force is applied by computer-controlled
actuators. The programmable nature of the force application allows
the device to simulate weight-training devices and other useful
exercise devices.
Inventors: |
Cobb; Tyson; (Pensacola,
FL) ; Craig; Travis; (Pensacola, FL) ; Gines;
Jeremy; (Pensacola, FL) ; Neuhaus; Peter;
(Pensacola, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Cobb; Tyson
Craig; Travis
Gines; Jeremy
Neuhaus; Peter |
Pensacola
Pensacola
Pensacola
Pensacola |
FL
FL
FL
FL |
US
US
US
US |
|
|
Family ID: |
1000005207281 |
Appl. No.: |
16/421780 |
Filed: |
May 24, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A63B 21/0428 20130101;
A63B 2220/51 20130101; A63B 24/0087 20130101; A63B 21/4033
20151001; A63B 2220/54 20130101; A63B 21/023 20130101; A63B 24/0062
20130101; A63B 2220/833 20130101; A63B 23/1281 20130101; A63B
21/156 20130101; A63B 2024/0093 20130101; A63B 23/03525
20130101 |
International
Class: |
A63B 24/00 20060101
A63B024/00; A63B 21/00 20060101 A63B021/00; A63B 21/04 20060101
A63B021/04; A63B 23/035 20060101 A63B023/035; A63B 21/02 20060101
A63B021/02; A63B 23/12 20060101 A63B023/12 |
Claims
1. An exercise device allowing a user to perform a variety of
exercises, comprising: (a) a right/column; (b) a left/column; (c) a
right/lower link connected to said right/column by a right/lower
universal joint; (d) a left/lower link connected to said
left/column by a left/lower universal joint; (e) a right/upper link
connected to said right/lower link by a right/powered pivot joint;
(f) a left/upper link connected to said left/lower link by a
left/powered pivot joint; (g) a bar, having a left end and a right
end; (h) said right end of said bar being connected to said
right/upper link by a right/upper universal joint; (i) said left
end of said bar being connected to said left/upper link by a
left/upper universal joint; and (j) a control system configured to
selectively vary a first torque applied to said right/powered pivot
joint and a second torque applied to said left/powered pivot
joint.
2. The exercise device as recited in claim 1, further comprising:
(a) a base connected to said right/column and said left/column; and
(b) a force plate mounted on said base, said force plate being
configured to measure a reaction force produced by said user.
3. The exercise device as recited in claim 2, wherein said control
system uses said reaction force to determine an instantaneous
center of pressure for said user.
4. The exercise device as recited in claim 3, wherein: (a) said
control system uses said instantaneous center of pressure to
determine a balance state of said user; and (b) said control system
is configured to remove said first and second torques in the even
that said user enters an unbalanced state.
5. The exercise device as recited in claim 2, wherein: (a) said
force plate is split into a left force plate and a right force
plate; and (b) said control system determines an left instantaneous
center of pressure of said left force plate and a right
instantaneous center of pressure for said right force plate.
6. The exercise device as recited in claim 1, further comprising:
(a) a right counterbalance mechanism applying a counterbalancing
force across said right/lower universal joint; and (b) a left
counterbalance mechanism applying a counterbalancing force across
said left/lower universal joint.
7. The exercise device as recited in claim 6, wherein: (a) said
right counterbalance mechanism includes, (i) a right/cam sheave
connected to said right/lower link, (ii) a right/cable having a
first end and a second end, (iii) a right/spring, (iv) said first
end of said right/spring being configured to move with said
right/lower link, (v) said right/cable passing around said
right/cam sheave, and (vi) said second end of said right/cable
being connected to said right/spring; (b) said left counterbalance
mechanism includes, (i) a left/cam sheave connected to said
left/lower link, (ii) a left/cable having a first end and a second
end, (iii) a left/spring, (iv) said first end of said left/spring
being configured to move with said left/lower link, (v) said
left/cable passing around said left/cam sheave, and (vi) said
second end of said left/cable being connected to said
left/spring;
8. The exercise device as recited in claim 1, wherein said control
system monitors a torque and a position of said right/powered joint
and said left/powered joint.
9. The exercise device as recited in claim 2, wherein said control
system monitors a torque and a position of said right/powered joint
and said left/powered joint.
10. The exercise device as recited in claim 3, wherein said control
system monitors a torque and a position of said right/powered joint
and said left/powered joint.
11. An exercise device allowing a user to perform a variety of
exercises, comprising: (a) a right/column; (b) a left/column; (c) a
right/carrier connected to said right/column by a right/first pivot
joint; (d) a left/carrier connected to said left/column by a
left/first pivot joint; (e) a right/lower link connected to said
right/carrier by a right/second pivot joint; (f) a left/lower link
connected to said left/carrier by a left/second pivot joint; (g) a
right/upper link connected to said right/lower link by a
right/powered pivot joint; (h) a left/upper link connected to said
left/lower link by a left/powered pivot joint; (i) a bar, having a
left end and a right end; (j) said right end of said bar being
connected to said right/upper link by a right/upper universal
joint; (k) said left end of said bar being connected to said
left/upper link by a left/upper universal joint; and (k) a control
system configured to selectively vary a first torque applied to
said right/powered pivot joint and a second torque applied to said
left/powered pivot joint.
12. The exercise device as recited in claim 11, further comprising:
(a) a base connected to said right/column and said left/column; and
(b) a force plate mounted on said base, said force plate being
configured to measure a reaction force produced by said user.
13. The exercise device as recited in claim 12, wherein said
control system uses said reaction force to determine an
instantaneous center of pressure for said user.
14. The exercise device as recited in claim 13, wherein: (a) said
control system uses said instantaneous center of pressure to
determine a balance state of said user; and (b) said control system
is configured to remove said first and second torques in the even
that said user enters an unbalanced state.
15. The exercise device as recited in claim 12, wherein: (a) said
force plate is split into a left force plate and a right force
plate; and (b) said control system determines an left instantaneous
center of pressure of said left force plate and a right
instantaneous center of pressure for said right force plate.
16. The exercise device as recited in claim 11, further comprising:
(a) a right counterbalance mechanism applying a counterbalancing
force across said right/first pivot joint; and (b) a left
counterbalance mechanism applying a counterbalancing force across
said left/first pivot joint.
17. The exercise device as recited in claim 16, wherein: (a) said
right counterbalance mechanism includes, (i) a right/cam sheave
connected to said right/lower link, (ii) a right/cable having a
first end and a second end, (iii) a right/spring, (iv) said first
end of said right/spring being configured to move with said
right/lower link, (v) said right/cable passing around said
right/cam sheave, and (vi) said second end of said right/cable
being connected to said right/spring; (b) said left counterbalance
mechanism includes, (i) a left/cam sheave connected to said
left/lower link, (ii) a left/cable having a first end and a second
end, (iii) a left/spring, (iv) said first end of said left/spring
being configured to move with said left/lower link, (v) said
left/cable passing around said left/cam sheave, and (vi) said
second end of said left/cable being connected to said
left/spring;
18. The exercise device as recited in claim 11, wherein said
control system monitors a torque and a position of said
right/powered joint and said left/powered joint.
19. The exercise device as recited in claim 12, wherein said
control system monitors a torque and a position of said
right/powered joint and said left/powered joint.
20. The exercise device as recited in claim 13, wherein said
control system monitors a torque and a position of said
right/powered joint and said left/powered joint.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] Not applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Funding for a portion of the development of this invention
was provided by the National Aeronautics and Space
Administration.
MICROFICHE APPENDIX
[0003] Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0004] The present invention pertains to the field of physical
exercise equipment. More specifically, the invention comprises a
powered device that can apply force to the body in a controlled
manner. The invention can mimic the forces applied by free weights
in established forms of exercise. The invention can also apply
unconventional forces that would not be possible using free weights
or other existing exercise equipment.
2. Description of the Related Art
[0005] Prior art exercise devices tend to use weights or resistance
schemes. Such devices are inherently limited in the type of forces
they can apply. In addition, such devices are often quite heavy.
The present invention seeks to overcome these known disadvantages
of the prior art devices, as well as providing other additional
advantages.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention comprises an exercise device where
force is applied by computer-controlled actuators. The programmable
nature of the force application allows the device to simulate
weight-training devices and other useful exercise devices. The
invention also includes reaction force measurement. In a preferred
embodiment the user is in a standing position and the reaction
forces produced by the user's feet are monitored. A control system
is used to monitor stability so that the forces can be altered if
the user enters an unbalanced state.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0007] FIG. 1 is a perspective view, showing an embodiment of the
inventive exercise device and a user.
[0008] FIG. 2 is a perspective view, showing the embodiment of FIG.
1 from another vantage point.
[0009] FIG. 3 is a detailed perspective view, showing an embodiment
in which two pivoting joints connect the lower links to the tops of
the support columns.
[0010] FIG. 4 is a detailed perspective view, showing the rotation
axes for the depiction of FIG. 3.
[0011] FIG. 5 is a rear elevation view, showing the operation of
the pivoting joints.
[0012] FIG. 6 is a sectional elevation view, showing a
ball-and-socket joint that is used in some embodiments to connect
the bar to the upper links.
[0013] FIG. 7 is a sectional elevation view, showing the
ball-and-socket joint of FIG. 6 in a pivoted state.
[0014] FIG. 8 is a side elevation view, showing the operation of
the counterbalance mechanism in the pivoting joints.
[0015] FIG. 9 is a side elevation view, showing the operation of
the counterbalance mechanism in the pivoting joints.
[0016] FIG. 10 is a conceptual view illustrating the operation of
the counterbalance mechanism.
[0017] FIG. 11 is a perspective view, showing the operation of the
invention.
[0018] FIG. 12 is a perspective view, showing the operation of the
invention.
[0019] FIG. 13 is a perspective view, showing the operation of the
invention.
[0020] FIG. 14 is a perspective view, showing how the vertical
position of the support columns can be altered to suit various
exercises.
[0021] FIG. 15 is a perspective view, showing the configuration of
FIG. 14 with a user in the low squat position.
[0022] FIG. 16 is a perspective view, with the embodiment of FIG. 1
being configured for a curl exercise.
[0023] FIG. 17 is a plan view of the force plate, showing an
exemplary stability polygon.
[0024] FIG. 18 is a plan view of a split force plate, showing
exemplary stability polygons.
[0025] FIG. 19 is a schematic view depicting an exemplary control
system that can be used with the present invention.
[0026] FIG. 20 is a side perspective view, with the embodiment of
FIG. 1 being configured for a bench press exercise.
[0027] FIG. 21 is a perspective view, showing the addition of two
linear joints to provide additional degrees of freedom.
[0028] FIG. 22 is a perspective view, showing the embodiment of
FIG. 1 from a different vantage point.
[0029] FIG. 23 is a perspective view, showing an additional
embodiment of the inventive device that allows a greater range of
vertical adjustment.
[0030] FIG. 24 is a perspective view, showing the embodiment of
FIG. 13 with the bar in an elevated position.
REFERENCE NUMERALS IN THE DRAWINGS
[0031] 10 user
[0032] 18 left/third pivot joint
[0033] 20 left/second pivot joint
[0034] 21 right/second pivot joint
[0035] 24 left/upper link
[0036] 26 left/lower link
[0037] 46 base
[0038] 50 bar
[0039] 52 right column
[0040] 54 left column
[0041] 56 left/end effector point
[0042] 58 left/actuator housing
[0043] 60 dogleg
[0044] 62 right/second pivot joint
[0045] 63 right/second pivot joint
[0046] 64 right/lower link
[0047] 66 right/third pivot joint
[0048] 68 right/upper link
[0049] 70 right/end effector point
[0050] 72 right/first pivot joint
[0051] 73 right/first pivot joint axis
[0052] 74 right/column cap
[0053] 76 right/carrier
[0054] 78 ball-and-socket joint
[0055] 80 cable
[0056] 82 guide roller
[0057] 84 cam sheave
[0058] 85 cable attachment point
[0059] 86 fairlead roller
[0060] 88 spring housing
[0061] 90 spring
[0062] 92 spring plate
[0063] 94 right/inner column
[0064] 96 flex conduit
[0065] 98 bench
[0066] 100 right/slide joint axis
[0067] 102 left/slide joint axis
[0068] 104 right/extended column
[0069] 106 left/extended column
[0070] 108 right/force plate
[0071] 110 left/force plate
[0072] 112 right/traveling mount
[0073] 114 left/traveling mount
[0074] 116 cable connection
[0075] 120 arm
[0076] 122 center of gravity
[0077] 124 cam
[0078] 126 spring
[0079] 128 bar axis
[0080] 130 load cell
[0081] 132 load cell
[0082] 134 load cell
[0083] 136 load cell
[0084] 138 instantaneous center of pressure
[0085] 140 printed reference
[0086] 142 stability polygon
[0087] 144 load cell
[0088] 146 load cell
[0089] 148 load cell
[0090] 150 load cell
[0091] 151 left stability polygon
[0092] 152 right stability polygon
[0093] 154 left center of pressure
[0094] 156 right center of pressure
[0095] 158 control system
[0096] 160 touchscreen display
DETAILED DESCRIPTION OF THE INVENTION
[0097] FIG. 1 depicts user 10 employing a preferred embodiment of
the inventive exercise device. The reader will note that the
inventive device includes many of the same components on its left
side and its right side, and in fact many embodiments are symmetric
with the exception of some control and monitoring features. A
convention will be used to describe the symmetric components. The
component name will be preceded by "left/" or "right/" to specify
the side of the device on which the component resides. The user
should bear in mind that the left and right version of a component
will generally be identical.
[0098] Base 46 provides a foundation for the device and preferably
houses some of the components needed. Right/column 52 and
left/column 54 extend upward from the base. Two links are pivotally
connected to each column. For example, left/lower link 26 is
pivotally connected to the top of left column 54 (In the preferred
embodiments this pivotal connection is complex and will be
described in more detail subsequently). Left/upper link 24 is
pivotally connected to left/lower link 26 by left/third pivot joint
18. The same structure of links is provided for the right side.
[0099] Bar 50 links the upper extremes of the left and right upper
links. In the preferred embodiments, a powered actuator is
configured to apply a controlled torque between each upper link and
lower link. For example, a powered actuator provides a controlled
torque across left/third pivot joint 18.
[0100] FIG. 2 provides a perspective view of the embodiment of FIG.
1 without the user. The reader will note that right/lower link 64
is pivotally connected to the top of right/column 52. Right/upper
link 68 is pivotally connected to right/lower link 64 by
right/third pivot joint 66. In this example, the actuators are
contained in the lower links (This need not always be the case).
For example, left/actuator housing 58 forms part of left/lower link
26. Right/actuator housing 59 forms part of right/lower link
64.
[0101] Left/end effector point 56 lies at the upper extreme of
left/upper link 24. Right/end effector point 70 lies at the upper
extreme of right/upper link 68. The actuators in this example are
electrical actuators that apply a controlled torque across the
pivot joint connecting each upper link to each lower link. As one
example, the actuators may be a linkage actuator such as described
in U.S. patent application Ser. No. 15/237,793. U.S. patent
application Ser. No. 15/237,793 is hereby incorporated by
reference, As those skilled in the art will recognize, the
application of a torque across left/third pivot joint 18 will
result in a force tending to urge left/end effector point 56 away
from the top of the left column or toward the top of the left
column. This is the basic operating principle of the device.
[0102] The inventive device is preferably provided with additional
degrees of freedom--which will now be explained in detail. FIG. 3
provides an enlarged view of the top of right/column 52.
Right/column cap 74 is secured to the top of the column.
Right/first pivot joint 72 pivotally connects right/carrier 76 to
right/column cap 74 as shown. Right/second pivot joint 62 pivotally
connects right/lower link 64 to right/carrier 76.
[0103] The two pivot joints shown are orthogonal. Those skilled in
the art will realize that a universal joint is thereby formed
(using the convention previously defined this universal joint will
be referred to as a right/lower universal joint and the identical
structure mounted atop the left/column in this embodiment will be
referred to as the left/lower universal joint). Right/first pivot
joint 72 allows right/carrier 76 to pivot about right/first pivot
joint axis 73 with respect to right/column cap 74 (as indicated by
the first reciprocating arrows shown in the view). Right/second
pivot joint 62 allows right/lower link 64 to pivot about
right/second pivot joint axis 63 with respect to right/carrier 76
(as indicated by the second reciprocating arrows shown in the
view).
[0104] FIG. 4 shows some additional details concerning the same
components. It is preferable to provide a "counterweight" mechanism
so that the static weight of the lower links, upper links, and bar
are counterbalanced irrespective of their position. FIG. 4
illustrates one embodiment for such a mechanism. Cam sheave 84 is
fixedly attached to right/lower link 64 so that it moves in unison
with the right/lower link. Cable 80 passes through a groove in the
outer perimeter of cam sheave 84 and is connected to cam sheave 84.
The cable then passes around guide sheave 82 and through fairlead
rollers 86. The cable then descends down and through spring housing
88. The lower portion of the cable is connected to spring plate 92,
which is positioned to press upward against compression spring
90.
[0105] When right/lower link 64 pivots downward about right/second
pivot joint axis 63, spring plate 92 moves upward and the
compression placed on spring 90 is increased. Thus, the mechanism
shown tends to counterbalance the weight of right/lower link 64
(and its connected upper link etc.). The reader will recall that
the right/lower link can pivot about both pivotal connections
depicted in FIG. 4.
[0106] Fairlead rollers 86 are provided to center the cable in the
middle of spring 90 despite the variations in the position of
right/lower link 64. FIG. 5 shows a rear elevation view of the same
mechanism. The reader will note that right/lower link 64 has been
pivoted laterally way from the vertical axis by an angle
.beta..sub.1. Fair lead rollers 86 center the cable despite the
pivoted state.
[0107] In order to accommodate the ability of the lower links to
pivot laterally (as shown in FIG. 5), an additional degree of
freedom is needed for the connection between bar 50 and the upper
links. FIGS. 6 and 7 show a preferred embodiment for this
connection. In FIG. 6, the reader will note the presence of
ball-and-socket joint 78 linking bar 50 to right/upper link 68 (in
the region of right/end effector point 70). Compressible cushion 69
is provided inside this joint to eliminate slack. The same type of
joint is located on the opposite end of bar 50. FIG. 7 shows the
same ball-and-socket joint in a deflected state. Cushion 69 has
compressed on one side to allow bar 50 to pivot with respect to
right/upper link 68.
[0108] The ball-and-socket joint depicted is a type of universal
joint. The joint connecting the right end of the bar to the
right/upper link will therefore be referred to as the right/upper
universal joint. The joint connecting the left end of the bar to
the left/upper link will be referred to as the left/upper universal
joint.
[0109] FIGS. 8-10 show additional details of a preferred embodiment
of a counterbalancing system. A cam (cam sheave 84) is used so that
the compression on the spring can be made non-linear and thereby
can be made to apply an effective counterbalance for the different
angular positions of the lower and upper links. The general
principles of the mechanism will be explained initially and then
some more advanced design constraints will be explained.
[0110] FIG. 8 shows the inventive exercise device with right/lower
link 64 in a moderately raised position. The centerline of
right/lower link 64 is resting at an angle .theta. measured in the
clockwise direction from the vertical axis depicted. As explained
previously, cable 80 is attached to spring plate 92. From that
point it passes around guide sheave 82 and cam sheave 84 before
connecting to the cam sheave at cable attachment point 85. Cam
sheave 84 is rigidly connected to right/lower link 64 so that it
pivots in unison with the right/lower link. Guide sheave 82 pivots
freely. Radius r is the instantaneous distance between right/second
pivot joint axis 63 and the point where the cable first makes
contact with cam sheave 84. This radius is variable. As the reader
will observe, the radius decreases as the angle .theta.
increases.
[0111] Another parameter is the level of compression of compression
spring 90. This is indicated by the distance y. In FIG. 8, the
distance y.sub.1 corresponds to the radius r.sub.1 and the angle
.theta..sub.1. In FIG. 9, the angle has increased to .theta..sub.2.
The radius has decreased to r.sub.2. The distance from the housing
to spring plate 92 has decreased to y.sub.2. In going from the
position of FIG. 8 to the position of FIG. 9, the reader will
appreciate that the compression of spring 90 has increased and that
the tension on cable 80 has also therefore increased. However, the
radius of the cable's contact with cam sheave 84 has decreased.
[0112] The objective of the counterbalance design is to equalize
the torques about right/second pivot joint axis 63. A clockwise
torque is produced by the weight of right lower link 64 (and its
other connected components). An anticlockwise torque is produced by
spring 90--acting through the cable connected to cam sheave 84. It
is possible to configure the spring constant (by selecting the
right spring wire size and pitch) and cam sheave profile so that
the torque about right/second pivot joint axis 63 is balanced (or
nearly balanced) for any angular position of right/lower link
64.
[0113] FIG. 10 shows a schematic depiction of the forces and
torques involved. Cam 124 pivots about a fixed point A. Arm 120 is
rigidly connected to cam 124. The arm has a center of gravity 122.
The weight of the arm can be considered a vertical force passing
through the center of gravity as shown. The center of gravity lies
a distance b from the rotation point A.
[0114] A counterbalancing spring 126 is added. The lower end of the
spring is connected to a fixed point. The upper end of the spring
passes around the earn and attaches to the cam at a point B on the
surface of the cam. It is possible to select a spring coefficient
and a cam profile so that arm 120 is perfectly counterbalanced at
any angular position .theta.. Once these proper selections are
made, a user can move arm 120 to any angular position and it will
remain in that position. The arm freely moves but is properly
counterbalanced at any position.
[0115] The selection of the correct spring constant and earn
profile is beyond the scope of this disclosure. However the reader
wishing to know more of the details of this process can refer to
U.S. Pat. No. 4,768,762 which describes the process in detail. U.S.
Pat. No. 4,768,762 is hereby incorporated by reference.
[0116] FIG. 11 shows a side perspective view of a preferred
embodiment of the present invention. The reader will note that the
counterbalancing problem is not quite as simple as the mechanism
shown in FIG. 10. In the present invention, the angular position of
right/upper link 68 varies with respect to right/lower link 64. The
center of gravity of the overall moving assembly therefore does not
remain perfectly constant. In the nomenclature of FIG. 10, the
distance b will vary somewhat for different angular positions of
the upper and lower links. However, it does not vary a great deal.
Thus, if the parameters for the counterbalancing mechanism shown in
FIGS. 8 and 9 are selected to counterbalance an average position
for the center of gravity they will provide effective (though
somewhat imperfect) counterbalancing across the entire range of
positions for the center of gravity.
[0117] FIGS. 11-13 serve to illustrate some of the operational
principles of the preferred embodiments. FIG. 11 shows the
invention with the lower links and upper links in the lowest
position. Bar axis 128 runs through the center of bar 50. In the
positions shown for the moving components the bar axis is
perpendicular to the page. The user interacts with the device (in
most configurations) by grasping the bar and exerting forces on the
bar. Axis A-A runs from right/second pivot joint 21 through
right/third pivot joint 66. Axis B-B runs from right/third pivot
joint 66 through bar axis 128. Axis C-C runs from right/second
pivot joint 21 through bar axis 128.
[0118] In this embodiment of the invention the actuators control
torque (and possibly angular position) across the third pivot
joints 18,66. The actuator in right/lower link 64 applies torque
across right/third pivot joint 66. In one exercise the user grasps
the bar and pulls the bar upward--creating a vertical force
P.sub.v. The reader will observe how this force F.sub.v passes
along the axis C-C. For this reason, the application of force by
the user does not tend to pivot right/lower link 64 about the
passive joint 21. Thus, controlling the torque about right/third
pivot joint 66 is sufficient to counteract the force applied by the
user (without having to power right/second pivot joint 21).
[0119] FIG. 12 shows the same embodiment with bar 50 raised to an
elevated position. The reader will note that bar 50 has been
allowed to move somewhat forward. In order to counteract the torque
applied by the actuator across right/third pivot joint 66, the user
must apply a force having a large vertical component F.sub.v and a
small horizontal component F.sub.h. In the position shown the axis
C-C has tilted off the vertical and this requires the user to add
the horizontal component to maintain a static balance where the
links are not moving. This balance is quite similar to that
required to keep a free weight steady. The user will instinctively
move the bar rearward (to the left in the view) to null the
horizontal component and make the balancing of the forces
easier.
[0120] FIG. 13 provides a perspective view with the same vantage
point as used in FIGS. 11 and 12. The reader will recall that bar
50 links the two sets of movable arms. Each side can be
independently controlled, as this view illustrates. The axes A-A
and B-B are in the same position as shown in FIG. 11. However, the
corresponding axes for left/lower link 26 and left upper/link 24
(axes A'-A' and B'-B') are rotated significantly.
[0121] This position can be the result of different things. As one
example, a control system can be set to apply constant torque
across the right and left powered joints 18, 66 while allowing the
angular position of these two joints to "float." If a user is much
stronger on the left side than the right (common in rehabilitation
exercises) then the left side of bar 50 may be propelled upward
much faster than the right. The inventive embodiment of FIG. 13 can
accommodate this condition, owing to the ball-and-socket joints 78
on each end of bar 50.
[0122] In order to accommodate the tilted configuration of the bar
present in FIG. 13, the two lower links will need to tilt toward
each other. This tilting is allowed via the first pivot joint axis
on each side (see first pivot joint axis 73 in FIG. 3). Thus, the
reader will understand that a user standing on the force plate can
move the bar laterally and angularly (in addition to moving it up
and down). The degrees of freedom provided in the invention allow
for these complex motions.
[0123] FIGS. 14-16 illustrate some exemplary exercises that can be
performed using the invention. FIG. 14 shows the starting position
for a squat exercise. Bar 50 has been placed across the user's
shoulders in a horizontal orientation. The reader will note that
the lower and upper links on both sides have been raised
significantly. It is desirable to accommodate a wide variety of
users and the squat exercise serves to illustrate the range of
heights needed.
[0124] A tall user (2.0 meters) will require a starting bar height
of about 1.7 meters. A small user will require a starting bar
height of only 1.0 meters. A wide range can be accommodated via the
pivoting of the upper link with respect to the lower link and the
pivoting of the lower link with respect to the column. However, it
is preferable to provide some adjustment in the height of the
columns themselves.
[0125] Still looking at FIG. 14, right column 52 telescopically
slides over right inner column 94. Likewise, left column 54
telescopically slides over a corresponding left inner column. In
the example shown an electrically-actuated screw drive is used to
raise and lower the columns 52, 54. The height of the columns can
be adjusted independently, but usually they will be configured to
move in unison. As shown, the columns 52, 54 have been raised so
that the starting position of bar 50 is realized without unduly
extending the upper and lower links.
[0126] FIG. 15 shows the low position of the squat exercise
commencing with FIG. 14. As is known to those skilled in the art, a
squat cycle requires the user to lift the bar from the position
shown in FIG. 15 up to the position shown in FIG. 14. During this
motion the control system of the present invention controls the
torque across third pivot joints 18, 66. The control system is
preferably a closed-loop system receiving angular position, angular
velocity, and torque information for each joint.
[0127] The control system can be used to mimic the forces of a free
weight. Consider two simple examples for a free weight: In the
first example the user moves the bar very slowly upward. In this
instance the dynamic forces are negligible and the user simply
counters gravity. In the second example the user moves the bar very
quickly. In this second instance the dynamic forces at the bottom
of the upward motion will be quite significant, and the force
required will be much greater. At the top of the motion the upward
velocity of the free weight is decreasing and momentum will cause
the overall force to be less than the force caused by gravity.
[0128] The control system can be configured to mimic these two
scenarios and everything in between. For the first instance the
control system varies the torque across third pivot joints 18, 66
so that the downward force on the bar remains constant. In the
second example the control system adds additional variation in the
torque across the pivot joints to mimic the dynamic forces of a
free weight.
[0129] FIG. 16 shows the invention configured for use in a prior
art curl exercise. Bar 50 occupies the starting position in this
view. The user lifts the bar through an arc to perform the curl.
The counterweight mechanism allows the starting position to be
achieved without the exertion of significant force. The control
system can be configured to allow passive manipulation to the
desired start position. The user then provides a start command and
the active control is initiated. The start command can he entered
by a touch screen, a foot-activated button, a voice command system,
or any other suitable method.
[0130] The simulation of free weight exercises is a significant
feature of the invention, but the invention is by no means limited
to these scenarios. In fact, a significant advantage of the
invention is its ability to mimic free weights in some aspects
while completely altering the force characteristics of free weights
in others. As one example, it is often desirable to alter the
lifting profile during the rehabilitation of a shoulder injury. A
physical therapist in this instance wishes to have the patient's
injured shoulder move through the range of motion of an overhead
press exercise without loading the joint. If the patient's right
shoulder is normal and the left shoulder is being rehabilitated,
the invention can be set to apply weight-mimicking loads to the
right shoulder and no loads to the left. The motion of the right
upper and lower links can even be set to be the "master" and the
motion of third pivot joint 18 (on the left side) can actually be
driven to match the motion of third pivot joint 66 (on the right
side). In this instance the left shoulder is actually assisted in
maintaining the position of the left end of bar 50. In other words,
the control system applies negative torque to the powered joint on
the right side (which the user must counter) while applying
positive torque to the powered joint on the left side to assist the
user in raising the injured joint.
[0131] The control system can also be configured to apply forces in
the following ways:
[0132] 1. A changeable force that increases or decreases over
different portions of the range of motion;
[0133] 2. A pulsing force;
[0134] 3. A free weight mimicking force that adds disturbing forces
to challenge or test the user;
[0135] 4. A changeable force that decreases over a particular
portion of the range of motion in order to reduce the chance of
exacerbating an existing injury.
[0136] It is advantageous to supply the control system with
reaction forces produced by the user's feet. Returning to FIG. 1,
the reader will note the presence of force plate 48 on base 46.
This force plate can be used to measure reaction forces. FIG. 17
shows a plan view of force plate 48. In the embodiment shown, load
cells 130,132,134,136 are placed on each corner. As those skilled
in the art will now, a load cell generally includes a strain gage
that is placed on a compression block. A monitoring system measures
the electrical characteristics of the strain gage (often a variable
voltage drop) and thereby determines the amount of force currently
being applied to the load cell.
[0137] Using the force information from the four load cells, the
control system can determine the reaction forces created by the
use's feet on the force plate. Reaction forces will of course
include the user's static weight. They will also include additional
varying forces produced in response to the user exerting force on
bar 50. The control system uses these reaction forces to compute an
instantaneous center of pressure 138 for the user. A stability
polygon 142 is defined within the software of the control system.
The stability polygon is a geometric boundary that contains all the
"safe" locations for instantaneous center of pressure 138. Printed
references 140 are provided to give the user a good starting
position for his or her feet. So long as the user's feet are near
these printed references, stability polygon 142 provides a good
definition of a balanced state. If the instantaneous center of
pressure moves outside of stability polygon 142, then the user is
off-balance. In this example the control system is programmed to
remove all forces once an off-balance state is detected. Thus, even
though the system can closely mimic the forces found with free
weights, it can also instantly remove the forces if a problem is
detected.
[0138] The control system can also be set to monitor the velocity
of the instantaneous center of pressure. This can be important in
detecting user imbalance. If the center of pressure is moving
rapidly toward the edge of the stability polygon--even though it
remains within the polygon--the control system can remove all
loads.
[0139] FIG. 18 shows an additional embodiment in which the force
plate is divided into two independently monitored force
plates--right force plate 108 and left force plate 110. Left force
plate 110 is equipped with four load cells 130,132,134, 136. Right
force place 108 is also equipped with four load cells
144,146,148,150. The split configuration allows the control system
to calculate an instantaneous center of pressure 154,156 for each
foot. A stability polygon 151,152 is also provided for each foot.
Loss-of-balance detection is carried out for each foot
individually, which can be helpful in cases of asymmetric strength
and/or balance.
[0140] Many different control systems can be used in the present
invention. FIG. 19 depicts an exemplary system. A processor runs
control software. An associated memory is provided for storing the
software and for storing the current state of the parameters used
in the control routine. The primary outputs for the processor are
the Motor Controllers and the I/O Module. Motor Controller 1
controls the motor applying torque across left/third pivot joint
18. Motor controller 2 controls the motor applying torque across
right/third pivot joint 66. The I/O Module provides the graphical
user interface that is preferably displayed on a touch screen (such
as display 160 shown in FIG. 1). The I/O Module takes information
from the processor and transforms it for display to the user. The
I/O module also receives user inputs (in the form of a screen touch
typically) and transforms these for use by the processor.
[0141] An important class of inputs for the processor are torque
measurements across the powered joints and position measurement
taken at the powered joints. The "Joint 1" measurements pertain to
left/third pivot joint 18 while the "Joint 2" measurements pertain
to right/third pivot joint 66. As those skilled in the art will
know, the joint torque will often be calculated as a function of
motor current. Joint position will often be measured by a rotary
encoder. Both these values may be fed through the motor controller.
Thus, there may be a single interface between each motor controller
and the processor, rather than a separate interface for torque and
position values.
[0142] An additional important class of inputs for the processor
are the reaction forces measured by the load cells supporting the
force plate or plates. Returning briefly to FIG. 17, the reader
will recall that force plate 48 is supported by four load cells
130, 132, 134, 136. In the schematic diagram of FIG. 19, these four
load cells are shown as additional inputs to the processor. The
force measurements provided by the load cells are used by the
processor to determine the instantaneous center of pressure and to
perform the stability calculations.
[0143] The control system can be configured to drive the use of the
invention for many different types of exercises. FIG. 20 shows the
invention being used for a bench-press exercise. Bench 98 has been
placed over base 46. The user lies on the bench and exerts force to
move bar 50 upward. In this configuration the reaction force
measurements from the force plate(s) are not available. Alternative
safety features can be programmed into the control system for this
situation. As an example, the user can "drop" the weight by ceasing
all upward force on the bar. This will initially cause a rapid
downward motion. The control system can be configured to interpret
such a rapid downward motion as a "drop" and respond by removing
the downward force and stabilizing the current position of the
powered joints.
[0144] Additional embodiments can provide additional degrees of
freedom. FIG. 21 provides an example of a useful additional degree
of freedom. In the embodiment shown a slide axis is added to the
top of each column. A slide joint allows right carrier 76 to slide
forward and backward with respect to right column cap 74. The
sliding motion takes place along right slide joint axis 100. Right
carrier 76 is able to slide along this axis. The lower link and
upper link move along with the right carrier. A similar slide joint
is added between the left carrier and left column cap. This second
slide joint allows the left column cap to move with respect to the
left column--along left slide joint axis 102. The presence of these
two slide joints allows more fore-and-aft motion of the bar during
exercises.
[0145] FIG. 22 provides a perspective view of a preferred
embodiment with the upper links raised to an elevated position. The
counterbalance mechanism present in the invention allows the
machine to remain in this state even when the bar is not grasped by
the user. The control system can be set to place the bar in such a
state before an exercise starts. The user then grasps the bar and
begins the exercise. The two carriers will tend to rotate somewhat
about the right and left first pivot joints. This rotation will
cause the bar to move laterally for a short distance. The user can
easily center the bar at the start of the exercise.
[0146] It is desirable to provide an embodiment that accommodate a
wide variety of exercises and a wide variety of users. FIGS. 23 and
24 show an additional embodiment that is capable of a significant
height variation. In FIG. 23, the user will note the provision of
right/extended column 104 and left/extended column 106. These are
significantly taller than the columns provided in the embodiment of
FIG. 1.
[0147] Right traveling mount 112 moves up and down on
right/extended column 104. Likewise, left traveling mount 114 moves
up and down on left/extended column 106. The position of the
traveling mounts can be altered and then fixed. Screw drives are a
good method of accomplishing this task.
[0148] Right/lower link 64 is attached to right traveling mount
112. A U-joint can be used for this connection (similar to the
2-axis U-joint shown in FIG. 3). In some embodiments a simple pivot
joint can be used (though this approach sacrifices the ability to
move bar 50 laterally). Right/upper link 68 is pivotally connected
to right/lower link 64 as for the prior embodiments (using a
powered joint).
[0149] In an analogous fashion, left/lower link 26 is pivotally
connected to left/traveling mount 114. Left/upper link 24 is
pivotally connected to left/lower link 26--again using a powered
joint. Bar 50 spans the upper portion of the two upper links. This
version uses two separate force plates 108, 110. FIG. 24 shows the
same embodiment with bar 50 raised to an elevated position. The
reader will note how the provision of the extended columns permits
bar 50 to travel to a higher position than is possible for the
embodiment of FIG. 1.
[0150] Returning now to the embodiment of FIG. 2, some general
observations about the operation of this embodiment can be made.
First the pivotal connection between the lower portion of the lower
links and the tops of the columns is preferably made via a
universal joint. Second, the connection between each end of bar 50
and its respective upper link is also made via a universal joint (a
ball-and-socket joint in the example provided). The degrees of
freedom provided therefore allow bar 50 to tilt with respect to
base 46. The bar can also move from side to side with respect to
the base. Fewer degrees of freedom can be provided if one is
willing to forego the lateral motion of the bar or the tilting
motion of the bar. It is also possible to provide additional
degrees of freedom if one wishes to allow the bar to move even more
freely--such as the sliding joints 100, 102 provided in the
embodiment of FIG. 21.
[0151] The use of a programmable control system allows many
different modes of operation. FIGS. 14 and 15 serve to illustrate
one example. FIG. 14 shows user 10 in the "high" position for a
squat exercise. The user sinks to a low position and then returns
to the high position to complete the exercise. Physical therapists
often wish to limit the flexion of the knee in a loaded state. FIG.
15 shows the low position. The user shown has a degree of flexion
that is beyond what a physical therapist would use in a
rehabilitation setting (at least for a loaded state). The control
system can be set to eliminate all applied force once bar 50 sinks
below a defined height above force plate 48. The user could sink
lower if he or she desires, but it would be in an unloaded state.
Once the user again lifts the bar above the defined height, the
force is reapplied. This height may be referred to as the "force
onset height." A maximum height for force-application can also be
defines.
[0152] Many more features can be found in the various embodiments
of the invention. These include:
[0153] 1. The limit of having a single actuator per side is that
the force can only be in one direction. To generate an arbitrary
force in a plane, an additional actuator can be added between the
lower links and the column caps, replacing the passive universal
joints. With these two actuators on the lower link, a force vector
in the plane of the actuator can be produced. This allows for the
generation of force fields and arbitrary neutral force paths.
[0154] 2. For the embodiment of FIG. 21, as the user moves the bar
forward and backward, the lower joint will move on the slide to
keep the distance between the lower joint and the end effector
minimized, thus keeping the force vertical.
[0155] 3. The function of the device is agnostic to the type of
actuator that is used. The only requirement for the actuator is
that is can produce an accurate torque based on the commanded
torque. In order to produce an accurate output torque, the actuator
can operate in either open-loop or closed-loop mode. To produce an
accurate torque in open-loop mode, a dynamic model of the
relationship between control signal and torque must be created that
accurately characterizes the system. To operate in closed-loop
mode, the actuator must include a torque or force sensing element,
which measures the torque that the actuator is applying. In this
mode, the sensed torque is compared to the desired torque and then
used to adjust the control signal to the actuator.
[0156] 4. One style of actuator is called the Linear Linkage
Actuator. This actuator features an internal mechanism to transfer
the torque from the motor to the output via a ball screw and
linkage system. This type of actuator is described more fully in
U.S. patent application Ser. No. 15/237,793, which is hereby
incorporated by reference. Another type of actuator features a
motor and a series of one or more speed reducers, which can be a
set of pulleys with belts, cables, or chains.
[0157] 5. The system can reproduce one of many resistance-type
exercises. These exercises can be performed standing (e.g. squats,
curls, deadlift, etc.) or sitting (bench press, inclined press,
seated rows, etc.). The device features two arms, positioned on
either side of the device. The arms can be connected with a bar to
perform bar style exercise, such as squats. The bar can also be
removed and replaced with individual hand grips. In this
configuration, the user can perform left and right arm exercises at
the same time, or use just one of the device's arms and perform
single arm at a time exercises.
[0158] 6. To accommodate various user heights and various
exercises, the vertical position of the lower joint might need to
be adjusted to keep the range of motion of the device inside of the
range of motion of the user for that particular exercise. The lower
joint can be mounted on a mechanism that can raise or lower the
position of the lower joint. This motion can be motorized, or can
be unpowered, requiring the user to make the adjustment manually.
If the motion is motorized, the position can be controlled by the
control system of the device. The settings for a given user and
exercise can be stored and then the device can automatically adjust
the height of the lower joint based on these stored settings. One
type of adjustment mechanism is telescoping tubes. Another type of
mechanism is a scissor type lift.
[0159] 7. The user will preferably control the device through a
screen and input device. The input could be a mouse and keyboard or
a touchscreen. The screen will display relevant settings about the
exercise to let the user change the various exercise settings.
During the exercise, the screen can display relevant information in
real-time about the exercise. This information can include feedback
on the center of pressure measurement, the pose of the user from
the motion capture system, heart rate, power, speed, force, etc. A
video stream of the user can also be augmented with graphical
information as determined by the computer, such as user skeleton
calculation, bar force vector, weak points of the motion, etc. The
screen can also display information to guide the user's motion.
[0160] 8. The user will preferably also be able to control the
device during the exercise from a set of buttons within reach of
the user's fingers. These buttons can be mounted on the bar for
exercises such as squat or curls. The buttons can be connected to
the computer system through either a wire or wireless connection.
The buttons can be used for things such as allowing the user to
start or stop the exercise, or increase or decrease the load. The
system can also be controlled through voice with a microphone via
voice-command input to the control system. The invention can also
be controlled through physical gestures made by the user with a
motion capture system monitoring the user's motion.
[0161] 9. For safety, the bar can also include a user contact
sensor. This will determine if the user releases the bar or hand
grip, in which case the system will remove the load from the
actuators. The control software can also incorporate a speed of
motion limitation.
[0162] 10. The device can have a single force plate which the user
stands on, that can measure the total load and the center of
pressure of the load. Or, the force plate can be split into two
independent force plates, one for the left foot, and one for the
right foot, which each plate able to measure the total load and the
center of pressure for the plate.
[0163] 11. The user's pose can be assessed in real-time via various
sensors that feed information to the control system. Form the pose,
the skeleton, or joint positions, of the user can be calculated
using software algorithms. There are several possible sensors to
accomplish the motion tracking, including one or more single lens
cameras, one or more stereo cameras, depth cameras (structured
light or time of flight), markerless motion capture (IMU), and
marker based motion capture. Software will process the data from
the motion capture system to produce an estimate of the user's body
position, including joint angles, in real time.
[0164] 12. The motion tracking can be used to confirm the type of
exercise that the user is performing. The motion tracking data can
also be used to analyze the motion of the user to determine correct
and incorrect form.
[0165] 13. Utilizing the sensor data from the force plate and the
user's pose from the motion capture, an algorithm can be written to
predict or detect the user's loss of balance during exercises in
which the user is standing. The algorithm will use the center of
pressure position data to calculate the velocity and acceleration
of the center of pressure and also establish a normal position and
movement pattern of the center of pressure. The algorithm will also
track the motion of the user and compare it to a standard motion
and the user's typical motions for the given exercises. From this
data, the algorithm can predict that the user will lose balance or
determine that the user has already lost balance. In either case,
the control system can take immediate action to prevent the user
from falling. This can include immediately reducing or removing the
load applied to the user.
[0166] 14. There are preferably position sensors on all active and
passive motions of the device. From the position data, the velocity
and acceleration of the endpoint of the mechanical interface
between the user and the device can be calculated.
[0167] 15. The device will also be able to integrate with a range
of physiological sensors. This can include heart rate, blood
pressure, oxygen saturation, respiration rate, and body
temperature. These sensors can have a wired or wireless connection
to the computer.
[0168] 16. Calculation of Force: The commanded force to the
actuator is determined by the onboard software-based control
system.
[0169] 17. The output force on each side can be adjusted hundreds
of times per seconds by the computer algorithm. This allows smooth
transitions.
[0170] 18. The force can be a function of many things, including
(a) Desired force by the user, (b) Desired force adjusted depending
on eccentric or concentric motion of the user, (c) The user's
physiological sensed data (heart rate, heart rate variability,
reparation rate, galvanic skin response, etc.), (d) The user's
pose, (e) The number of repetitions, (f) The speed at which the
user is moving the bar (e.g. if stall is detected, the force can be
lowered), (g) The biomechanical muscle length, (h) The acceleration
of the bar or other endpoint to simulate inertial forces, and (i)
The velocity of the bar or endpoint to simulate viscous forces
[0171] 19. In addition to the software desired force, a
perturbation force can be applied. This perturbation force is a
short duration force which occurs in a random or apparently random
fashion based on a predetermined probability. This perturbation
mode can be used is an assessment tool or a training tool. As an
assessment, the response of the user to the series of perturbations
is recorded. The response can consist of motion of the user, motion
of the user's center of pressure, and motion of the bar. The
pattern of perturbations can be stored and applied during
assessment sessions with the same user, thus being able to track
the user's response to identical (yet seemingly random)
perturbations over time.
[0172] 20. Instead of operating in mode where the applied force is
specified, the device can operate where the desired position is
specified and the force the user is applying is measured. This mode
is referred to as isometric (where the desired position is not
changing) or isokinetic (where the desired position is changing at
a constant rate). These modes are used to assess the strength of
the user.
[0173] 21. The device can be used to detect or highlight muscle
weakness in certain positions, muscle injury, or muscle impairment.
By monitoring the position, velocity, acceleration, and power
during force controlled motions, the evolution of the data pattern
can be compared to healthy patterns to determine an abnormal
behavior. By comparing left and right patterns, compensatory
movements and motions can also be identified.
[0174] 22. Blood Flow Restriction (BFR) is a form of exercise where
the blood flow to the extremities is restricted. The inventive
exercise device can be used in conjunction with BFR exercise to
control the pressure in the cuffs that are used to restrict the
blood flow. In BFR exercises, completing the desired number of
repetitions can be more important than the resistance weight.
Therefore, during BFR exercises, the device can monitor the user's
motion and reduce the weight in order to ensure that the user
completes the proscribed number of repetitions.
[0175] 23. The inventive device can record, store, and upload all
of the data that constitutes an exercise. This includes, the motion
of the device, the motion of the user, video of the user, and any
physiological data of the user. Facial recognition algorithms can
be used to automatically identify the user and link the data to all
of the previous data sets for that user. After a set of exercises,
the user's data can be processed and analyzed. Various algorithms
can be utilized to look for improvements or reductions in
performance, muscle weakness or injury, and other conditions. This
data can also but uploaded to a cloud server for remote analysis by
a human trainer or artificial intelligence algorithm.
[0176] The preceding description contains significant detail
regarding the novel aspects of the present invention. It is should
not be construed, however, as limiting the scope of the invention
but rather as providing illustrations of the preferred embodiments
of the invention. Many other variations are possible, and the
drawings presented depict only a few of these possible variations.
Thus, the scope of the invention should be fixed by the claims,
rather than by the examples given.
* * * * *