Running specific prostheses and orthoses

When people run their body behaves like a simple spring-mass system. For people with lower limb impairments their running ability can be restored or enhanced using assistive technology that supports this behavior in the leg. For amputees this application is well known as their conventional prosthetic feet are replaced by carbon blades. Also for people with weakness of the ankle muscles carbon blades could be supplied to take over the spring like action of the ankle muscles. Running performance with these devices depens much on finding the right stiffness characteristics of these blades and on the interaction of the user with these blades, that can be considered as a spring in series with the apparent spring in the biological residual leg. In a series of projects the properties of running prosthetic and orthotic blades are investigated with specific attention on the question how the interaction between user and blade affects the running performance.