STTR Phase II:Integrated Powered Knee-Ankle Prosthetic System

This Small Business Technology Transfer (STTR) Phase II project proposes the development of an integrated powered knee-ankle prosthesis. The objective of this proposal is to investigate the use of integrated powered knee and ankle joints in trans-femoral prostheses that use sensory information from the ground and the wearer. The hypothesis is that a prosthesis with actively powered knee and ankle joints will significantly enhance the mobility of trans-femoral amputees while walking on level grounds, as well as stairs and slopes. The inability to deliver power to prosthetic systems has significantly impaired their ability to restore many locomotive functions. This proposal will derive a set of guidelines on design and control of an integrated powered knee and ankle prosthetic system which will improve locomotion function such as walking up stairs, walking up slopes, running, jumping, and as hypothesized in this proposal, even level walking. The proposed work will result in new theoretical frameworks for control and sensory systems, and the design of such systems. Major intellectual contributions will include the design of power systems; development of the sensory system to obtain information from the ground and from the user; the development of a control framework for the interactive control of prostheses; and the development of adaptive and robust controllers for impedance modulation during locomotion. This project intends to create principles that provide significantly greater functional capabilities for above-knee amputees. Specifically, our work will enable more natural, stable, and adaptable prostheses. These research elements in this proposal will also form a foundation for powered orthotic systems. Additional significant benefits of this work include fostering a broader awareness and increased sensitivity of young engineers and educational institutions to disability issues. Limb loss is also afflicting a growing number of military personnel serving in recent conflicts, as well as a far larger number of veterans from previous wars. The recent Middle East conflicts have resulted in a number of young amputees, many of whom still shoulder the responsibility of raising families and anticipate a working life ahead of them. The integrated knee-ankle prosthetic proposed here will have a direct impact on the mobility of the trans-femoral amputees and their quality of life, and most likely alleviate the long-term consequences related to musculoskeletal health.