Systematic methodology for the design of a flexible keel for energy-storing prosthetic feet

Citation
Ts. Jang et al., Systematic methodology for the design of a flexible keel for energy-storing prosthetic feet, MED BIO E C, 39(1), 2001, pp. 56-64
Citations number
20
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary,"Instrumentation & Measurement
Journal title
MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING
ISSN journal
0140-0118 → ACNP
Volume
39
Issue
1
Year of publication
2001
Pages
56 - 64
Database
ISI
SICI code
0140-0118(200101)39:1<56:SMFTDO>2.0.ZU;2-C
Abstract
An effective design method is suggested for a flexible keel design for ener gy-storing prosthetic feet (ESPF). The basic, two-dimensional shape of the keel is based on anthropometric data and normal gait analysis available in the literature. Cost function is defined for the performance evaluation of the keel. Five factors and five levels of their effect on the performance o f the keel are established. By use of an orthogonal array table, 25 trials of dynamic simulations of prosthetic walking are designed, from among 3125 possible combinations, dramatically reducing the number of total simulation s needed to examine sufficiently the contribution of each factor to cost fu nction. A prosthetic walking model is built, and a dynamic simulation of pr osthetic walking is performed using the finite element method. The contribu tion of each factor to cost function is investigated by an analysis of vari ance (ANOVA), and the average main effects of factors for cost function are calculated. The optimum combination of factor levels is obtained by minimi sation of cost function. To examine the structural safety of the keel, the deformation and stress distribution of the keel are investigated by static analysis, and failure indices are calculated by three failure criteria. Fin ally, the optimum flexible keel is designed with increased energy storage c apacity, without failure, and suitable for more active prosthetic walking; the recoverable strain energy stored in the optimum ESPF keel is 25.8J.