Please use this identifier to cite or link to this item: http://hdl.handle.net/1946/4396
User Control of Lower Limb Prostheses
To move and positions one´s limbs as desired is generally taken for granted, but this is not the case for lower limb amputees who can only impose their will upon a prosthetic limb by moving it. This project is concerned with significantly improving the possibilities for amputees to control a prosthetic limb as if it were a natural limb. Specifically the first goal of this project was to investigate available methods for detecting user intent and utilise them as a control signal for a lower limb prosthesis. The second goal was to select one method and demonstrate the feasibility of using it to control a lower limb prosthesis.
Four suitable methods for detecting user intent were identified, namely electromyography, mechanomyography, pressure sensing and flexion sensing. Mechanomyography(detecting sound waves caused by muscle vibration) was selected for further development. Silicone embedded sensors were constructed and mounted in a prototype socket for normal subject testing and used to control a prosthetic ankle.
The results clearly demonstrate the feasibility of using mechanomyography to control a prosthetic ankle, with an 83% movement classification accuracy To improve this system filtering techniques must be optimized. It is therefore concluded that mechanomyography is a suitable and promising technology to capture an amputee’s conscious will and by extension improve his quality of life.