Abstract

In this article, we present an integrated human-in-the-loop simulation paradigm for the design and evaluation of a lower extremity exoskeleton that is elastically strapped onto human lower limbs. The exoskeleton has three rotational DOFs on each side and weighs 23 kg. Two torque compensation controllers of the exoskeleton are introduced, aiming to minimize interference and maximize assistance, respectively. Their effects on the wearer's biomechanical loadings are studied with a running motion and predicted ground reaction forces (GRFs). It is found that the added weight of the passive exoskeleton substantially increases the wearer's musculoskeletal loadings. The maximizing assistance controller reduces the knee joint torque by 31% when compared with the normal running (without exoskeleton) and by 50% when compared with the passive exoskeleton case. When compared with the normal running, this controller also reduces the hip flexion and extension torques by 31% and 38%, respectively. As a result, the peak activations of the biceps short head, gluteus maximus, and rectus femoris muscles are reduced by more than a half. Nonetheless, the axial knee joint reaction force increases for all exoskeleton cases due to the added weight and higher ground reaction forces. In summary, the results provide sound evidence of the efficacy of the proposed controllers on reducing the wearer's musculoskeletal loadings. And it is shown that the human-in-the-loop simulation paradigm presented here can be used for virtual design and evaluation of powered exoskeletons and pave the way for building optimized exoskeleton prototypes for experimental evaluation.

References

References
1.
Sawicki
,
G. S.
,
Beck
,
O. N.
,
Kang
,
I.
, and
Young
,
A. J.
,
2020
, “
The Exoskeleton Expansion: Improving Walking and running economy
,”
J. Neuroeng. Rehabil.
,
17
(
1
), pp.
1
9
.10.1186/s12984-020-00663-9
2.
Sankai
Y.
,
2010
,
HAL: Hybrid Assistive Limb Based on Cybernics
,
M.
Kaneko
,
Y.
Nakamura
, eds., Robotics Research, Springer Tracts in Advanced Robotics, Vol.
66
,
Springer
,
Berlin
.10.1007/978-3-642-14743-2_3
3.
Wehner
,
M.
,
Quinlivan
,
B.
,
Aubin
,
P. M.
,
Martinez-Villalpando
,
E.
,
Baumann
,
M.
,
Stirling
,
L.
,
Holt
,
K.
,
Wood
,
R.
, and
Walsh
,
C.
,
2013
, “
A Lightweight Soft Exosuit for Gait Assistance
,”
2013 IEEE International Conference on Robotics and Automation
,
Karlsruhe, Germany
, May 6–10, pp.
3362
3369
.10.1109/ICRA.2013.6631046
4.
Gregorczyk
,
K. N.
,
Hasselquist
,
L.
,
Schiffman
,
J. M.
,
Bensel
,
C. K.
,
Obusek
,
J. P.
, and
Gutekunst
,
D. J.
,
2010
, “
Effects of a Lower-Body Exoskeleton Device on Metabolic Cost and Gait Biomechanics During Load Carriage
,”
Ergonomics
,
53
(
10
), pp.
1263
1275
.10.1080/00140139.2010.512982
5.
Herr
,
H.
,
2009
, “
Exoskeletons and Orthoses: Classification, Design Challenges and Future Directions
,”
J. Neuroeng. Rehabil.
,
6
(
1
), p.
21
.10.1186/1743-0003-6-21
6.
Ferris
,
D. P.
, and
Lewis
,
C. L.
,
2009
, “
Robotic Lower Limb Exoskeletons Using Proportional Myoelectric Control
,”
Annual International Conference of the IEEE Engineering in Medicine and Biology Society
,
Minneapolis, MN
, Sept. 3–6, pp.
2119
2124
.10.1109/IEMBS.2009.5333984
7.
Kawamoto
,
H.
,
Lee
,
S.
,
Kanbe
,
S.
, and
Sankai
,
Y.
,
2003
, “
Power Assist Method for HAL-3 Using EMG-Based Feedback Controller
,”
2003 IEEE International Conference on Systems, Man and Cybernetics. System Security and Assurance (Cat. No.03CH37483)
,
Washington, DC
, Oct. 8, Vol.
2
, pp.
1648
1653
.10.1109/ICSMC.2003.1244649
8.
Guizzo
,
E.
, and
Goldstein
,
H.
,
2005
, “
The Rise of the Body Bots
,”
IEEE Spectr.
,
42
(
4
), pp.
42
49
.10.1109/MSPEC.2005.1413730
9.
Kazerooni
,
H.
,
Racine
,
J. L.
,
Huang
,
L. H. L.
, and
Steger
,
R.
,
2005
, “
On the Control of the Berkeley Lower Extremity Exoskeleton (BLEEX)
,”
Proceedings of the 2005 IEEE International Conference on Robotics and Automation
, April 18–22,
Barcelona, Spain
, pp.
4364
4371
.10.1109/ROBOT.2005.1570790
10.
Zoss
,
A. B. Z. A. B.
,
Kazerooni
,
H. K. H.
, and
Chu
,
A. C. A.
,
2006
, “
Biomechanical Design of the Berkeley Lower Extremity Exoskeleton (BLEEX)
,”
IEEE/ASME Trans. Mechatr.
,
11
(
2
), pp.
128
138
.10.1109/TMECH.2006.871087
11.
Meijneke
,
C.
,
van Dijk
,
W.
, and
van der Kooij
,
H.
,
2014
, “
Achilles: An Autonomous Lightweight Ankle Exoskeleton to Provide Push-off Power
,”
Fifth IEEE RAS/EMBS International Conference on Biomedical Robotics and Biomechatronics
,
Sao Paulo, Brazil
, Aug. 12–15, pp.
918
923
.10.1109/BIOROB.2014.6913898
12.
Bai
,
S.
, and
Rasmussen
,
J.
,
2011
, “
Modelling of Physical Human-Robot Interaction for Exoskeleton Designs
,”
Proceedings of Multibody Dynamics 2011, ECCOMAS Thematic Conference
,
Brussels, Belgium
, July 4–7.https://www.researchgate.net/publication/233782910_Modelling_of_Physical_Human-Robot_Interaction_for_Exoskeleton_Designs
13.
Ferrati
,
F.
,
Bortoletto
,
R.
, and
Pagello
,
E.
,
2013
, “
Virtual Modelling a Real Exoskeleton Constrained to a Human Musculoskeletal Model
,”
Living Machines
,
London, UK
, July 29–Aug. 2, pp.
96
107
.10.1007/978-3-642-39802-5_9
14.
Agarwal
,
P.
,
Kuo
,
P.-H.
,
Neptune
,
R. R.
, and
Deshpande
,
A. D.
,
2013
, “
A Novel Framework Virtual Prototyping Rehabilitation Exoskeletons
,”
IEEE Int. Conf. Rehabil. Robot.
,
2013
,
Seattle, WA
, June 24–26, pp.
1
6
.10.1109/ICORR.2013.6650382
15.
ChoKim
,
K.
,
Yi
,
Y.
,
Jung
,
D. M.
, and
Lee
,
K.
,
2012
, “
Analysis and Evaluation of a Combined Human–Exoskeleton Model Under Two Different Constraints Condition
,”
Proceedings of the International Summit on Human Simulation
,
St. Pete Beach, FL
, May 20–22, pp.
1
10
.https://www.researchgate.net/publication/263505202_Analysis_and_evaluation_of_a_combined_human_-_exoskeleton_model_under_two_different_constraints_condition
16.
Delp
,
S. L.
,
Anderson
,
F. C.
,
Arnold
,
A. S.
,
Loan
,
P.
,
Habib
,
A.
,
John
,
C. T.
,
Guendelman
,
E.
, and
Thelen
,
D. G.
,
2007
, “
OpenSim: Open-Source Software to Create and Analyze Dynamic Simulations of Movement
,”
IEEE Trans. Biomed. Eng.
,
54
(
11
), pp.
1940
1950
.10.1109/TBME.2007.901024
17.
Damsgaard
,
M.
,
Rasmussen
,
J.
,
Christensen
,
S. T.
,
Surma
,
E.
, and
de Zee
,
M.
,
2006
, “
Analysis of Musculoskeletal Systems in the AnyBody Modeling System
,”
Simul. Modell. Pract. Theory
,
14
(
8
), pp.
1100
1111
.10.1016/j.simpat.2006.09.001
18.
Zhou
,
L.
,
Bai
,
S.
,
Andersen
,
M. S.
, and
Rasmussen
,
J.
,
2015
, “
Modeling and Design of a Spring-Loaded, Cable-Driven, Wearable Exoskeleton for the Upper Extremity
,”
Model., Identif. Control
,
36
(
3
), pp.
167
177
.10.4173/mic.2015.3.4
19.
Koller
,
J. R.
,
Jacobs
,
D. A.
,
Ferris
,
D. P.
, and
Remy
,
C. D.
,
2015
, “
Learning to Walk With an Adaptive Gain Proportional Myoelectric Controller for a Robotic Ankle Exoskeleton
,”
J. Neuroeng. Rehabil.
,
12
(
1
), p.
97
.10.1186/s12984-015-0086-5
20.
Dembia
,
C. L.
,
Silder
,
A.
,
Uchida
,
T. K.
,
Hicks
,
J. L.
, and
Delp
,
S. L.
,
2017
, “
Simulating Ideal Assistive Devices to Reduce the Metabolic Cost of Walking With heavy loads
,”
PloS One
,
12
(
7
), p.
e0180320
.10.1371/journal.pone.0180320
21.
Uchida
,
T. K.
,
Seth
,
A.
,
Pouya
,
S.
,
Dembia
,
C. L.
,
Hicks
,
J. L.
, and
Delp
,
S. L.
,
2016
, “
Simulating Ideal Assistive Devices to Reduce the Metabolic Cost of Running
,”
PloS One
,
11
(
9
), p.
e0163417
.10.1371/journal.pone.0163417
22.
Delp
,
S. L.
,
Loan
,
J. P.
,
Hoy
,
M. G.
,
Zajac
,
F. E.
,
Topp
,
E. L.
, and
Rosen
,
J. M.
,
1990
, “
An Interactive Graphics-Based Model of the Lower Extremity to Study Orthopaedic Surgical Procedures
,”
IEEE Trans. Biomed. Eng.
,
37
(
8
), pp.
757
67
.10.1109/10.102791
23.
Jung
,
Y.
,
Jung
,
M.
,
Ryu
,
J.
,
Yoon
,
S.
,
Park
,
S.-K.
, and
Koo
,
S.
,
2016
, “
Dynamically Adjustable Foot-Ground Contact Model to Estimate Ground Reaction Force During Walking and running
,”
Gait\Posture
,
45
, pp.
62
68
.10.1016/j.gaitpost.2016.01.005
24.
Zhou
,
X.
, and
Przekwas
,
A.
,
2011
, “
A Fast and Robust Whole-Body Control Algorithm for Running
,”
Int. J. Human Factors Modell. Simul.
,
2
(
1/2
), pp.
127
148
.10.1504/IJHFMS.2011.041641
25.
Hamner
,
S. R.
,
Seth
,
A.
, and
Delp
,
S. L.
,
2010
, “
Muscle Contributions to Propulsion and Support During Running
,”
J. Biomech.
,
43
(
14
), pp.
2709
16
.10.1016/j.jbiomech.2010.06.025
26.
Zhou
,
X.
,
Whitley
,
P.
, and
Przekwas
,
A.
,
2014
, “
A Musculoskeletal Fatigue Model for Prediction of Aviator Neck Manoeuvring Loadings
,”
Int. J. Human Factors Modell. Simul.
,
4
(
3/4
), pp.
191
29
.10.1504/IJHFMS.2014.067174
27.
Zhou
,
X.
,
Sun
,
K.
,
Roos
,
P.
,
Li
,
P.
, and
Corner
,
B.
,
2016
, “
Anthropometry Model Generation Based on ANSUR II Database
,”
Int. J. Digit. Human
,
1
(
4
), pp.
321
343
.10.1504/IJDH.2016.084584
28.
Whitley
,
P. E.
, and
Roos
,
P. E.
,
2017
, “
Comparison of Gender Specific and Anthropometrically Scaled Musculoskeletal Model Predictions Using the Sorensen Test
,”
Advances in Human Factors in Simulation and Modeling. AHFE 2017. Advances in Intelligent Systems and Computing
, Vol.
591
,
Springer
,
Cham
, pp.
469
477
.
29.
Roos
,
P. E.
,
Vasavada
,
A.
,
Zheng
,
L.
, and
Zhou
,
X.
,
2020
, “
Neck Musculoskeletal Model Generation Through Anthropometric Scaling
,”
Plos One
,
15
(
1
), p.
e0219954
.10.1371/journal.pone.0219954
30.
Erdemir
,
A.
,
McLean
,
S.
,
Herzog
,
W.
, and
van den Bogert
,
A. J.
,
2007
, “
Model-Based Estimation of Muscle Forces Exerted During Movements
,”
Clin. Biomech. (Bristol, Avon)
,
22
(
2
), pp.
131
154
.10.1016/j.clinbiomech.2006.09.005
31.
Cappellini
,
G.
,
Ivanenko
,
Y. P.
,
Poppele
,
R. E.
, and
Lacquaniti
,
F.
,
2006
, “
Motor Patterns in Human Walking and running
,”
J. Neurophysiol.
,
95
(
6
), pp.
3426
3437
.10.1152/jn.00081.2006
32.
Bergmann
,
G.
,
Bender
,
A.
,
Graichen
,
F.
,
Dymke
,
J.
,
Rohlmann
,
A.
,
Trepczynski
,
A.
,
Heller
,
M. O.
, and
Kutzner
,
I.
,
2014
, “
Standardized Loads Acting in Knee Implants
,”
PloS One
,
9
(
1
), p.
e86035
.10.1371/journal.pone.0086035
33.
Tamez-Duque
,
J.
,
Cobian-Ugalde
,
R.
,
Kilicarslan
,
A.
,
Venkatakrishnan
,
A.
,
Soto
,
R.
, and
Contreras-Vidal
,
J. L.
,
2015
, “
Real-Time Strap Pressure Sensor System for Powered Exoskeletons
,”
Sensors
,
15
(
2
), pp.
4550
4563
.10.3390/s150204550
34.
Belda-Lois
,
J.
,
Poveda
,
R.
, and
Vivas
,
M.
,
2008
, “
5.6 Case Study: Analysis of Pressure Distribution and Tolerance Areas for Wearable Robots
,”
Wear. Robot. Biomechatr. Exoskelet.
, p.
154
.
35.
Zhou
,
X.
, and
Mont
,
A.
,
2020
, “
Evaluation of a 1-DOF Hand Exoskeleton for Neuromuscular Rehabilitation
,”
Computer Methods, Imaging and Visualization in Biomechanics and Biomedical Engineering, Selected Papers From the 16th International Symposium CMBBE and 4th Conference on Imaging and Visualization
,
New York
, Aug. 14–16,
2019
, pp.
384
397
.https://arxiv.org/abs/1907.07311
36.
von Marcard
,
T.
,
Rosenhahn
,
B.
,
Black
,
M. J.
, and
Pons‐Moll
,
G.
,
2017
, “
Sparse Inertial Poser: Automatic 3d Human Pose Estimation From Sparse Imus
,”
Comput. Graph. Forum
,
36
(
2
), pp.
349
360
.10.1111/cgf.13131
37.
Schut
,
I.
,
Pasma
,
J.
,
Roelofs
,
J.
,
Weerdesteyn
,
V.
,
van der Kooij
,
H.
, and
Schouten
,
A.
,
2020
, “
Estimating Ankle Torque and Dynamics of the Stabilizing Mechanism: No Need for Horizontal Ground Reaction Forces
,”
J. Biomech.
,
106
, p.
109813
.10.1016/j.jbiomech.2020.109813
38.
Braun
,
B. J.
,
Veith
,
N. T.
,
Hell
,
R.
,
Döbele
,
S.
,
Roland
,
M.
,
Rollmann
,
M.
,
Holstein
,
J.
, and
Pohlemann
,
T.
,
2015
, “
Validation and Reliability Testing of a New, Fully Integrated Gait Analysis Insole
,”
J. Foot Ankle Res.
,
8
(
1
), p.
54
.10.1186/s13047-015-0111-8
39.
Zell
,
P.
, and
Rosenhahn
,
B.
,
2020
, “
Learning Inverse Dynamics for Human Locomotion Analysis
,”
Neural Comput. Appl.
,
32
(
15
), pp.
11729
11743
.10.1007/s00521-019-04658-z
40.
Fluit
,
R.
,
Andersen
,
M. S.
,
Kolk
,
S.
,
Verdonschot
,
N.
, and
Koopman
,
H. F. J. M.
,
2014
, “
Prediction of Ground Reaction Forces and Moments During Various Activities of Daily Living
,”
J. Biomech.
,
47
(
10
), pp.
2321
2329
.10.1016/j.jbiomech.2014.04.030
You do not currently have access to this content.