The actuation systems of lower limbs exoskeletons have been extensively investigated and, presently, a great effort is aimed at reducing the weight and improving the efficiency, thus increasing the operating range for battery-operated devices. In this work, an innovative and more efficient actuation system to power the knee joint is proposed. The key and nonconventional elements of this alternative design are a flywheel and a micro infinitely variable transmission (IVT). This particular powertrain configuration permits to exploit efficiently the dynamics of human locomotion, which offers the possibility to recover energy. By means of simulations of level ground walking and running, it is here demonstrated how storing energy in the flywheel permits to reduce the energy consumption and to downsize the electric motor.

References

1.
Dollar
,
A. M.
, and
Herr
,
H.
,
2008
, “
Lower Extremity Exoskeletons and Active Orthoses: Challenges and State-of-the-Art
,”
IEEE Trans. Rob.
,
24
(
1
), pp.
144
158
.
2.
Chen
,
X.
,
Gao
,
F.
,
Qi
,
C.
,
Tian
,
X.
, and
Zhang
,
J.
,
2014
, “
Spring Parameters Design for the New Hydraulic Actuated Quadruped Robot
,”
ASME J. Mech. Rob.
,
6
(
2
), p.
021003
.
3.
Grimmer
,
M.
,
Eslamy
,
M.
, and
Seyfarth
,
A.
,
2014
, “
Energetic and Peak Power Advantages of Series Elastic Actuators in an Actuated Prosthetic Leg for Walking and Running
,”
Actuators
,
3
(
1
), pp.
1
19
.
4.
Mooney
,
L.
, and
Herr
,
H.
,
2013
, “
Continuously-Variable Series-Elastic Actuator
,”
IEEE International Conference on Rehabilitation Robotics
(
ICORR
), Seattle, WA, June 24–26.
5.
Durfee
,
W. K.
, and
Rivard
,
A.
,
2005
, “
Design and Simulation of a Pneumatic, Stored-Energy, Hybrid Orthosis for Gait Restoration
,”
ASME J. Biomech. Eng.
,
127
(
6
), pp.
1014
1019
.
6.
Van den Bogert
,
A. J.
,
Samorezov
,
S.
,
Davis
,
B. L.
, and
Smith
,
W. A.
,
2012
, “
Modeling and Optimal Control of an Energy-Storing Prosthetic Knee
,”
ASME J. Biomech. Eng.
,
134
(
5
), p.
051007
.
7.
Farley
,
C. T.
, and
Ferris
,
D. P.
,
1998
, “
10 Biomechanics of Walking and Running: Center of Mass Movements to Muscle Action
,”
Exercise Sport Sci. Rev.
,
26
(
1
), pp.
253
286
http://journals.lww.com/acsm-essr/Fulltext/1998/00260/10_Biomechanics_of_Walking_and_Running__Center_of.12.aspx.
8.
Walsh
,
C. J.
,
Paluska
,
D.
,
Pasch
,
K.
,
Grand
,
W.
,
Valiente
,
A.
, and
Herr
,
H.
,
2006
, “
Development of a Lightweight, Underactuated Exoskeleton for Load-Carrying Augmentation
,”
IEEE International Conference on Robotics and Automation
(
ICRA 2006
), Orlando, FL, May 15–19, pp.
3485
3491
.
9.
Kawamoto
,
H.
, and
Sankai
,
Y.
,
2002
, “
Power Assist System HAL-3 for Gait Disorder Person
,”
Computers Helping People With Special Needs
, Vol.
2398
,
Springer
,
Berlin
, pp.
196
203
.
10.
Pratt
,
J. E.
,
Krupp
,
B. T.
,
Morse
,
C. J.
, and
Collins
,
S. H.
,
2004
, “
The RoboKnee: An Exoskeleton for Enhancing Strength and Endurance During Walking
,”
IEEE International Conference on Robotics and Automation
(
ICRA '04
), New Orleans, LA, Apr. 26–May 1, pp.
2430
2435
.
11.
Zoss
,
A.
, and
Kazerooni
,
H.
,
2006
, “
Design of an Electrically Actuated Lower Extremity Exoskeleton
,”
Adv. Rob.
,
20
(
9
), pp.
967
988
.
12.
Haeufle
,
D. F. B.
,
Taylor
,
M. D.
,
Schmitt
,
S.
, and
Geyer
,
H.
,
2012
, “
A Clutched Parallel Elastic Actuator Concept: Towards Energy Efficient Powered Legs in Prosthetics and Robotics
,”
4th IEEE, RAS and EMBS International Conference on Biomedical Robotics and Biomechatronics
(
BioRob
), Rome, June 24–27, pp.
1614
1619
.
13.
Luciano
,
V.
,
Sardini
,
E.
,
Serpelloni
,
M.
, and
Baronio
,
G.
,
2012
, “
Analysis of an Electromechanical Generator Implanted in a Human Total Knee Prosthesis
,”
IEEE Sensors Applications Symposium
(
SAS
), Brescia, Italy, Feb. 7–9.
14.
Donelan
,
J. M.
,
Li
,
Q.
,
Naing
,
V.
,
Hoffer
,
J. A.
,
Weber
,
D. J.
, and
Kuo
,
A. D.
,
2008
, “
Biomechanical Energy Harvesting: Generating Electricity During Walking With Minimal User Effort
,”
Science
,
319
(
5864
), pp.
807
810
.
15.
Bergelin
,
B. J.
,
Mattos
,
J. O.
,
Wells
,
J. G.
, and
Voglewede
,
P. A.
,
2010
, “
Concept Through Preliminary Bench Testing of a Powered Lower Limb Prosthetic Device
,”
ASME J. Mech. Rob.
,
2
(
4
), p.
041005
.
16.
Borràs
,
J.
, and
Dollar
,
A. M.
,
2014
, “
Actuation Torque Reduction in Parallel Robots Using Joint Compliance
,”
ASME J. Mech. Rob.
,
6
(
2
), p.
021006
.
17.
Hutter
,
M.
,
Remy
,
C. D.
,
Hoepflinger
,
M. A.
, and
Siegwart
,
R.
,
2011
, “
High Compliant Series Elastic Actuation for the Robotic Leg ScarlETH
,”
14th International Conference on Climbing and Walking Robots
(CLAWAR), Paris, Sept. 6–8, Paper No. EPFL-CONF-175826.
18.
Lagoda
,
C.
,
Schouten
,
A. C.
,
Stienen
,
A. H.
,
Hekman
,
E. E.
, and
Van der Kooij
,
H.
,
2010
, “
Design of an Electric Series Elastic Actuated Joint for Robotic Gait Rehabilitation Training
,”
3rd IEEE, RAS and EMBS International Conference on Biomedical Robotics and Biomechatronics
(
BioRob
), Tokyo, Sept. 26–29, pp.
21
26
.
19.
Sergi
,
F.
,
Accoto
,
D.
,
Carpino
,
G.
,
Tagliamonte
,
N. L.
, and
Guglielmelli
,
E.
,
2012
, “
Design and Characterization of a Compact Rotary Series Elastic Actuator for Knee Assistance During Overground Walking
,”
4th IEEE, RAS and EMBS International Conference on Biomedical Robotics and Biomechatronics
(
BioRob
), Rome, June 24–27, pp.
1931
1936
.
20.
Veneman
,
J. F.
,
Ekkelenkamp
,
R.
,
Kruidhof
,
R.
,
van der Helm
,
F. C.
, and
Van der Kooij
,
H.
,
2006
, “
A Series Elastic-and Bowden-Cable-Based Actuation System for Use as Torque Actuator in Exoskeleton-Type Robots
,”
Int. J. Rob. Res.
,
25
(
3
), pp.
261
281
.
21.
Bharadwaj
,
K.
,
Sugar
,
T. G.
,
Koeneman
,
J. B.
, and
Koeneman
,
E. J.
,
2005
, “
Design of a Robotic Gait Trainer Using Spring Over Muscle Actuators for Ankle Stroke Rehabilitation
,”
ASME J. Biomech. Eng.
,
127
(
6
), pp.
1009
1013
.
22.
Accoto
,
D.
,
Carpino
,
G.
,
Sergi
,
F.
,
Tagliamonte
,
N. L.
,
Zollo
,
L.
, and
Guglielmelli
,
E.
,
2013
, “
Design and Characterization of a Novel High-Power Series Elastic Actuator for a Lower Limb Robotic Orthosis
,”
Int. J. Adv. Rob. Syst.
,
10
(359), pp. 1–12.
23.
Paluska
,
D.
, and
Herr
,
H.
,
2006
, “
The Effect of Series Elasticity on Actuator Power and Work Output: Implications for Robotic and Prosthetic Joint Design
,”
Rob. Auton. Syst.
,
54
(
8
), pp.
667
673
.
24.
Hollander
,
K. W.
,
Ilg
,
R.
,
Sugar
,
T. G.
, and
Herring
,
D.
,
2006
, “
An Efficient Robotic Tendon for Gait Assistance
,”
ASME J. Biomech. Eng.
,
128
(
5
), pp.
788
791
.
25.
Pratt
,
G. A.
, and
Williamson
,
M. M.
,
1995
, “
Series Elastic Actuators
,”
IEEE/RSJ International Conference on Intelligent Robots and Systems, Human Robot Interaction and Cooperative Robots
(
IROS
), Pittsburgh, Aug. 5–9, pp.
399
406
.
26.
Rouse
,
E. J.
,
Mooney
,
L. M.
,
Martinez-Villalpando
,
E. C.
, and
Herr
,
H. M.
,
2013
, “
Clutchable Series-Elastic Actuator: Design of a Robotic Knee Prosthesis for Minimum Energy Consumption
,”
IEEE International Conference on Rehabilitation Robotics
(
ICORR
), Seattle, WA, June 24–26.
27.
Endo
,
K.
,
Paluska
,
D.
, and
Herr
,
H.
,
2006
, “
A Quasi-Passive Model of Human Leg Function in Level-Ground Walking
,”
IEEE/RSJ International Conference on Intelligent Robots and Systems
(IROS)
, Beijing, Oct. 9–15, pp.
4935
4939
.
28.
Bottiglione
,
F.
, and
Mantriota
,
G.
,
2013
, “
Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems
,”
ASME J. Mech. Des.
,
135
(
6
), p.
061001
.
29.
Lewis
,
C. L.
, and
Ferris
,
D. P.
,
2011
, “
Invariant Hip Moment Pattern While Walking With a Robotic Hip Exoskeleton
,”
J. Biomech.
,
44
(
5
), pp.
789
793
.
30.
Bazyn
,
M.
,
Carter
,
J.
,
Lohr
,
C. B.
,
Malone
,
C.
,
McDaniel
,
L. T.
, and
Poxton
,
P. D.
,
2002
, “
Continuously and/or Infinitely Variable Transmissions and Methods Therefor
,” U.S. Patent No. 8,313,405.
31.
Brown
,
L. G.
,
Brown
,
G. A.
, and
Brown
,
B. A.
,
2013
, “
Locked Contact Infinitely Variable Transmission
,” U.S. Patent No. US8419589 B1.
32.
Greenwood
,
C. J.
,
De Freitas
,
A. D.
, and
Oliver
,
A. R.
,
2011
, “
Drive Mechanism for Infinitely Variable Transmission
,” U.S. Patent No. US7955210 B2.
33.
Kazerounian
,
K.
, and
Furu-Szekely
,
Z.
,
2006
, “
Parallel Disk Continuously Variable Transmission (PDCVT)
,”
Mech. Mach. Theory
,
41
(
5
), pp.
537
566
.
34.
Lohr
,
C. B.
,
Sherrill
,
J. W.
,
Pohl
,
B. P.
,
Dawson
,
R.
, and
Pew
,
C.
,
2014
, “
Infinitely Variable Transmissions, Continuously Variable Transmissions, Methods, Assemblies, Subassemblies, and Components Therefor
,” U.S. Patent No. US8721485 B2.
35.
Douglas
,
M.
,
2010
, “
Infinitely Variable Transmission
,” U.S. Patent No. US7704184 B2.
36.
Bottiglione
,
F.
, and
Mantriota
,
G.
,
2011
, “
Reversibility of Power-Split Transmissions
,”
ASME J. Mech. Des.
,
133
(
8
), p.
084503
.
37.
Carbone
,
G.
,
Mangialardi
,
L.
, and
Mantriota
,
G.
,
2004
, “
A Comparison of the Performance of Full and Half Toroidal Traction Drives
,”
Mech. Mach. Theory
,
39
(
9
), pp.
921
942
.
38.
Mangialardi
,
L.
, and
Mantriota
,
G.
,
1999
, “
Power Flows and Efficiency in Infinitely Variable Transmissions
,”
Mech. Mach. Theory
,
34
(
7
), pp.
973
994
.
39.
Mantriota
,
G.
,
2002
, “
Performances of a Parallel Infinitely Variable Transmission With a Type II Power Flow
,”
Mech. Mach. Theory
,”
37
(
6
), pp.
555
578
.
40.
Mantriota
,
G.
,
2002
, “
Performances of a Series Infinitely Variable Transmission With a Type I Power Flow
,”
Mech. Mach. Theory
,
37
(
6
), pp.
579
597
.
41.
Carbone
,
G.
,
Mangialardi
,
L.
, and
Mantriota
,
G.
,
2002
, “
Fuel Consumption of a Mid Class Vehicle With Infinitely Variable Transmission
,”
SAE Trans. J. Engines
,
110
(
3
), pp.
2474
2483
.
42.
Carbone
,
G.
,
Mangialardi
,
L.
, and
Mantriota
,
G.
,
2002
, “
Influence of Clearance Between Plates in Metal Pushing V-Belt Dynamics
,”
ASME J. Mech. Des.
,
124
(
3
), pp.
543
557
.
43.
Mantriota
,
G.
, and
Pennestrì
,
E.
,
2003
, “
Theoretical and Experimental Efficiency Analysis of Multi D.O.F. Epicyclic Gear Trains
,”
Multibody Syst. Dyn.
,
9
(
5
), pp.
389
408
.
44.
De Pinto
,
S.
, and
Mantriota
,
G.
,
2014
, “
A Simple Model for Compound Split Transmissions
,”
Proc. Inst. Mech. Eng., Part D
,
228
(
5
), pp.
547
562
.
45.
De Pinto
,
S.
,
Bottiglione
,
F.
, and
Mantriota
,
G.
,
2014
, “
Infinitely Variable Transmissions in Neutral Gear: Torque Ratio and Power Re-Circulation
,”
Mech. Mach. Theory
,
74
, pp.
285
298
.
46.
Mangialardi
,
L.
, and
Mantriota
,
G.
,
1996
, “
Dynamic Behaviour of Wind Power Systems Equipped With Automatically Regulated Continuously Variable Transmission
,”
Renewable Energy Int. J.
,
7
(
2
), pp.
185
203
.
47.
Mantriota
,
G.
,
2005
, “
Fuel Consumption of a Vehicle With Power Split CVT System
,”
Int. J. Veh. Des.
,
37
(
4
), pp.
327
342
.
48.
Schafer
,
I.
,
Bourlier
,
P.
,
Hantschack
,
F.
,
Roberts
,
E. W.
,
Lewis
,
S. D.
,
Forster
,
D. J.
, and
John
,
C.
,
2005
, “
Space Lubrication and Performance of Harmonic Drive Gears, 11th European Space Mechanisms and Tribology Symposium
(
ESMATS 2005
), Lucerne, Switzerland, Sept. 21–23, pp. 65–72.
49.
Mantriota
,
G.
,
2001
, “
Infinitely Variable Transmissions With Automatic Regulation
,”
Proc. Inst. Mech. Eng., Part D
,
215
(
12
), pp.
1267
1280
.
50.
Mangialardi
,
M.
, and
Mantriota
,
G.
,
1994
, “
Continuously Variable Transmissions With Torque-Sensing Regulators in Waterpumping Windmills
,”
Renewable Energy
,
4
(
7
), pp.
807
823
.
51.
Bottiglione
,
F.
,
Carbone
,
G.
,
De Novellis
,
L.
,
Mangialardi
,
L.
, and
Mantriota
,
G.
,
2013
, “
Mechanical Hybrid KERS Based on Toroidal Traction Drives: An Example of Smart Tribological Design to Improve Terrestrial Vehicle Performance
,”
Adv. Tribol.
,
2013
, p.
918387
.
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