Gravity balancing is often used in industrial machines to decrease the required actuator efforts during motion. In this paper, we present a new design for gravity balancing of the human leg using an external orthosis. This external orthosis is connected to the human leg on the shank and its other end is fixed to a walking frame. The major issues addressed in this paper are as follows: (i) design for gravity balancing of the human leg and the orthosis, (ii) kinematic compatibility of the human leg and the external orthosis during walking, and (iii) comparison of the joint torque trajectories of the human leg with and without external orthosis. We illustrate feasible 2D and 3D designs of the external orthosis through computer simulations. Our results show that the 3D design has smaller inertia with respect to 2D design, which can be more helpful for typical stroke patients to walk in a balanced position.

1.
Rahman
,
T.
,
Sample
,
W.
,
Seliktar
,
R.
,
Alexander
,
M.
, and
Scavina
,
M.
, 2000, “
A Body-Powered Functional Upper Limb Orthosis
,”
J. Rehabil. Res. Dev.
0748-7711,
37
(
6
), pp.
675
680
.
2.
Agrawal
,
S. K.
,
Gardner
,
G.
, and
Pledgie
,
S.
, 2001, “
Design and Fabrication of a Gravity Balanced Planar Mechanism Using Auxiliary Parallelograms
,”
ASME J. Mech. Des.
0161-8458,
123
(
4
), pp.
525
528
.
3.
Cardoso
,
L. F.
,
Tomazio
,
S.
, and
Herder
,
J. L.
, 2002, “
Conceptual Design of a Passive Arm Orthosis
,”
Proceedings of the American Society of Mechanical Engineering Design Engineering Technical Conference
,
ASME
,
New York
.
4.
Ruthenberg
,
B. J.
,
Wasylewski
,
N. A.
, and
Beard
,
J. E.
, 1997, “
An Experimental Device for Investigating the Force and Power Requirements of a Powered Gait Orthosis
,”
J. Rehabil. Res. Dev.
0748-7711,
34
(
2
), pp.
203
213
.
5.
Aoyagi
,
D.
,
Ichinose
,
W. E.
,
Harkema
,
S. J.
,
Reinkensmeyer
,
D. J.
, and
Bobrow
,
J. E.
, 2005, “
An Assistive Robotic Device That Can Synchronize to the Pelvic Motion During Human Gait Training
” IEEE Ninth International Conference on Rehabilitation Robotics, pp.
565
568
.
6.
Colombo
,
G.
,
Joerg
,
M.
,
Schreier
,
R.
, and
Dietz
,
V.
, 2000, “
Treadmill Training of Paraplegic Patients Using a Robotic Orthosis
,”
J. Rehabil. Res. Dev.
0748-7711,
37
(
6
), pp.
693
700
.
7.
Hesse
,
S.
, and
Uhlenbrock
,
D.
, 2000, “
A Mechanized Gait Trainer for Restoration of Gait
,”
J. Rehabil. Res. Dev.
0748-7711,
37
(
6
), pp.
701
708
.
8.
Banala
,
S. K.
,
Agrawal
,
S. K.
,
Fattah
,
A.
,
Krishnamoorthy
,
V.
,
Hsu
,
W. L.
,
Scholz
,
J.
, and
Rudolph
,
K.
, 2006, “
Gravity-Balancing Leg Orthosis and Its Performance Evaluation
,” the
IEEE Transactions on Robotics
,
22
(
6
), pp.
1228
1239
.
9.
Agrawal
,
S. K.
, and
Fattah
,
A.
, 2004, “
Theory and Design of an Orthotic Device for Full or Partial Gravity-Balancing of a Human Leg During Motion
,”
IEEE Trans. Neural Syst. Rehabil. Eng.
1534-4320,
12
(
2
), pp.
157
165
.
10.
Mankala
,
K. K.
, and
Agrawal
,
S. K.
, 2007, “
Passive Swing Assistive Exoskeletons for Motor-Incomplete Spinal Cord Injury Patients
,”
IEEE International Conference on Robotics and Automation
,
IEEE
,
Rome, Italy
, pp.
3761
3766
.
11.
Kawamoto
,
H.
, and
Sankai
,
Y.
, 2002, “
Power Assist System HAL-3 for Gait Disorder Person
,”
International Conference on Computers for Handicapped Persons
, Vol.
2398
, pp.
196
203
.
12.
Galvez
,
J. A.
,
Kerdanyan
,
G.
,
Maneekobkunwong
,
S.
,
Weber
,
R.
,
Scott
,
M.
,
Harkema
,
S. J.
, and
Reinkensmeyer
,
D. J.
, 2005, “
Measuring Human Trainers Skill for the Design of Better Robot Control Algorithms for Gait Training After Spinal Cord Injury
,”
IEEE International Conference on Rehabilitation Robotics
,
IEEE
,
New York
, pp.
231
234
.
13.
Surdilovic
,
D.
, and
Bernhardt
,
R.
, 2004, “
String-Man: A Novel Wire Robot for Gait Rehabilitation
,”
IEEE International Conference on Robotics and Automation
,
IEEE
,
New York
, Vol.
2
, pp.
2031
2036
.
14.
Sandor
,
G. N.
, and
Erdman
,
A. G.
, 2001,
Advanced Mechanism Design: Analysis and Synthesis
,
Prentice-Hall
,
Englewood Cliffs, NJ
, Vol.
2
.
15.
Streit
,
D. A.
, and
Gilmore
,
B. J.
, 1989, “
Perfect Spring Equilibrators for Rotatable Bodies
,”
ASME J. Mech., Transm., Autom. Des.
0738-0666,
111
(
4
), pp.
451
458
.
16.
NASA
, 1978, “
Anthropometric Source Book: Volume I: Anthropometry for Designers
,” NASA Reference Publication No. 1024.
17.
Angeles
,
J.
, 1997,
Fundamentals of Robotic Mechanical Systems: Theory, Methods, and Algorithms
,
Springer-Verlag
,
New York
.
18.
Perry
,
J.
, 1989,
Observational Gait Analysis Handbook
,
The Professional Staff Association
,
Downey, CA
.
19.
Craig
,
J. J.
, 2005,
Introduction to Robotics: Mechanics and Control
,
3rd ed.
,
Pearson Education
,
Upper Saddle River, NJ
.
You do not currently have access to this content.