The great divide - the human-machine interface. Issues in the control of prostheses, manipulators, and other human machine systems

The shortage of physiologically appropriate independent control sources is probably the biggest impediment to the development and fitting of significantly more functional artificial limb replacements. The use of open-loop velocity control with visual feedback to control today´s externally-powered artificial limb replacements further impedes the development of high performance multifunctional prostheses. Velocity control places an excessive mental burden on the user thereby limiting the number of degrees-of freedom that can be controlled in parallel. Both these issues and the implications they might have for the future control of multifunctional artificial limb replacements are explored.