Body powered hand prostheses require high physical user effort. This is caused by the stiffness of the cosmetic covering, or cosmetic glove. This paper aims to present a new concept of a mechanism for the compensation of the nonlinear stiffness of body powered hand prostheses by using static balancers with a nonlinear behavior. This concept is based on a cooperative action of snap-through behavior in multiple bi-stable spring mechanisms to create the nonlinear balancing force. To demonstrate the efficiency of the concept, an optimized design for a case study of a child-size hand prosthesis is also presented. A pattern search method was applied for the optimization. As a result, the calculated stiffness and thereby the operating effort was reduced by 96%. It can be concluded from the conceptual and numerical results that the presented concept provides a highly efficient solution to the discussed problem.

Issue Section:
Research Papers
Keywords:
static balancing, stiffness compensation, cosmetic gloves, hand prosthesis
Topics:
Prostheses, Stiffness, Design, Optimization, Displacement, Springs

References

1.
Smit
,
G.
, and
Plettenburg
,
D. H.
, “
Efficiency of Voluntary Closing Hand and Hook Prostheses
,”
Prosthet. Orthot Int.
,
34
(4)
, pp.
411
–
427
.
PubMed
 
2.
Corin
,
J.
,
Holley
,
T. M.
,
Hasler
,
R. A.
, and
Ashman
,
R. B.
, 1987, “
Mechanical Comparison of Terminal Devices
,”
Clin. Prosthet. Orthot.
,
11
, pp.
235
–
244
.
3.
LeBlanc
,
M.
,
Setoguchi
,
Y.
,
Shaperman
,
J.
, and
Carlson
,
L.
, 1992, “
Mechanical Work Efficiencies of Body-Powered Prehensors for Young Children
,”
Child. Prosthet Orthot Clin.
,
27
(
3
), pp.
70
–
75
.
4.
Herder
,
J. L.
,
Cool
,
J. C.
, and
Plettenburg
,
D. H.
, 1998, “
Methods for Reducing Energy Dissipation in Cosmetic Gloves
,”
J. Rehabil. Res. Dev.
,
35
(
2
), pp.
201
–
209
.
PubMed
 
5.
Shaperman
,
J.
,
Leblanc
,
M.
,
Setoguchi
,
Y.
, and
McNeal
,
D. R.
, 1995, “
Is Body Powered Operation of Upper Limb Prostheses Feasible for Young Limb Deficient Children?
”
Prosthet. Orthot Int.
,
19
(
3
), pp.
165
–
175
.
PubMed
 
6.
Wang
,
Y.
, and
Lakes
,
R.
, 2004, “
Extreme Stiffness Systems due to Negative Stiffness Elements
,”
Am. J. Phys.
,
27
(
1
), pp.
40
–
50
.
Crossref
Search ADS
 
7.
Herder
,
J. L.
, 1998, “
Design of Spring Force Compensation Systems
,”
Mech. Mach. Theory
,
33
(
1–2
), pp.
151
–
161
.
8.
Tolou
,
N.
, and
Herder
,
J. L.
, 2009, “
Concept and Modeling of a Statically Balanced Compliant Laparoscopic Grasper
,”
Proceedings of the ASME DETC Biennial, Mechanisms and Robotics Conference
, 2009, San Diego, California, USA.
9.
Tolou
,
N.
,
Henneken
,
V. A.
, and
Herder
,
J. L.
, 2010, “
Statically Balanced Compliant Micro Mechanisms (SB-MEMS): Concepts and Simulation
,”
Proceedings of the ASME DETC Biennial, Mechanisms and Robotics Conference
, 2010, Montréal, Québec, Canada.
10.
Chen
,
G.
, and
Zhang
,
S.
, “
Fully-Compliant Statically-Balanced Mechanisms Without Prestressing Assembly: Concepts and Case Studies
,”
Mech. Sci.
,
2
,
169
–
174
.
Crossref
Search ADS
 
11.
Ahmadian
,
M. T.
, and
Nikooyan
,
A. A.
, 2006, “
Modeling and Prediction of Soft Tissue Directional Stiffness Using In-Vitro Force-Displacement Data
,”
Int. J. Sci. Res.
,
16
, pp.
385
–
389
.
12.
Lewis
,
R.
, and
Torczon
,
V.
, 1999, “
Pattern Search Algorithms for Bound Constrained Minimization
,”
SIAM J. Optim.
,
9
, pp.
1082
–
1099
.
Crossref
Search ADS
 
13.
Torczon
,
V.
, 1997, “
On the Convergence of Pattern Search Algorithms
,”
SIAM J. Optim.
,
7
(
1
), pp.
1
–
25
.
Crossref
Search ADS
 
14.
Dunning
,
G. A.
,
Tolou
,
N.
, and
Herder
,
J. L.
, 2011, “
Review Article: Inventory of Platforms Towards the Design of a Statically Balanced Six Degrees of Freedom Compliant Precision Stage
,”
Mech. Sci.
,
2
, pp.
157
–
168
.
Crossref
Search ADS
 
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 by American Society of Mechanical Engineers
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