Abstract:
The human ankle provides a significant amount of net positive work during the stance period of
walking, especially at moderate to fast walking speeds. On the contrary, conventional ankle-foot
prostheses are completely passive during stance, and consequently, cannot provide net positive
work. Clinical studies indicate that trans-tibial amputees using conventional prostheses exhibit
higher gait metabolic rates as compared to intact individuals. Researchers believe the main cause for
the observed increase in metabolism is due to the inability to provide net positive work at terminal
stance in walking. The objective of this project is build and run a prototype of an intelligent
powered ankle foot prosthesis based on electromyography, capable of providing active mechanical
power at terminal stance, can improve amputee metabolic walking economy compared to a passive
or passive-elastic prosthesis. A powered prosthesis is designed and built that comprises a
unidirectional spring, configured in parallel with a force-controllable actuator with series elasticity.
The prosthesis is controlled to mimic human ankle walking behavior, in particular, the power
generation characteristics observed in normal human walking
