A robotic tendon is a spring based, linear actuator in which the stiffness of the spring is crucial for its successful use in a lightweight, energy efficient, powered ankle orthosis. Like its human analog, the robotic tendon uses its inherent elastic nature to reduce both peak power and energy requirements for its motor. In the ideal example, peak power required of the motor for ankle gait is reduced from 250 W to just 77 W. In addition, ideal energy requirements are reduced from nearly 36 J to just 21 J. Using this approach, an initial prototype has provided 100% of the power and energy necessary for ankle gait in a compact 0.95kg package, seven times less than an equivalent motor/gearbox system.

1.
Hollander
,
K. W.
, and
Sugar
,
T. G.
, 2004, “
Concepts for Compliant Actuation in Wearable Robotic Systems
US-Korea Conference (UKC) CDROM
.
2.
(Online), 2004, Website, BLEEX project description, Berkeley Robotics and Human Engineering Laboratory, URL http://bleex.me.berkeley.edu/bleex.htmhttp://bleex.me.berkeley.edu/bleex.htm.
3.
Kawamoto
,
H.
, and
Sankai
,
Y.
, 2002, “
Comfortable Power Assist Control Method for Walking Aid by HAL-3
,”
In IEEE International Conference on Systems
, Man and Cybernetics, Vol.
4
, pp.
6
11
.
4.
Kawamoto
,
H.
,
Kanbe
,
S.
, and
Sankai
,
Y.
, 2003, “
Power Assist Method for HAL-3 Estimating Operator’s Intention Based on Motion Information
,” in IEEE International Workshop on Robot and Human Interactive Communication, pp.
67
72
.
5.
Sugar
,
T. G.
, and
Kumar
,
V. J.
, 1998, “
Design and Control of a Compliant Parallel Manipulator for a Mobile Platform
,” in
ASME Design Engineering Technical Conferences and Computers in Engineering Conference (DETC) CDROM
.
6.
Sugar
,
T. G.
, 2002, “
A Novel Selective Compliant Actuator
,”
Mechatronics
0957-4158,
12
(
9–10
), pp.
1157
1171
.
7.
Robinson
,
D. W.
,
Pratt
,
J. E.
,
Paluska
,
D. J.
, and
Pratt Gill
,
A.
, 1999, “
Series Elastic Actuator Development for a Biomimetric Walking Robot
,” in
IEEE/ASME International Conference on Advanced Intelligent Mechatronics
, pp.
561
568
.
8.
Pratt
,
J. E.
,
Krupp
,
B. T.
, and
Morse Christopher
,
J.
, 2004, “
The RoboKnee: An Exoskeleton for Enhancing Strength and Endurance During Walking
,” in
IEEE International Conference on Robotics and Automation (ICRA)
, pp.
2430
2435
.
9.
Blaya
,
J. A.
, and
Herr
,
H.
, 2004, “
Adaptive Control of a Variable-Impedance Ankle-Foot Orthosis to Assist Drop-Foot Gait
,”
IEEE Trans. Neural Syst. Rehabil. Eng.
1534-4320,
12
(
1
), pp.
24
31
.
10.
Raibert
,
M. H.
, 1986,
Legged Robots that Balance
,
MIT Press
, Cambridge.
11.
Hurst
,
J. W.
,
Chestnutt
,
J.
, and
Rizzi
,
A.
, 2004, “
An Actuator with Mechanically Adjustable Series Compliance
,” Technical Report No. CMU-RI-TR-04-24,
Robotics Institute, Carnegie Mellon University
, Pittsburgh, PA, April.
12.
Whittle
,
M. W.
, 1996,
Gait Analysis: An Introduction
, 2nd ed.,
Butterworth-Heinemann
, Oxford.
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