Considering Limb Impedance in the Design and Control of Prosthetic Devices

Abstract

The mechanical properties of our limbs and how those properties are regulated by the nervous system endow us with the ability to interact with our environment in numerous predictable and effective ways. While there have been many recent advances in the design and control of prosthetic limbs, none yet have the capacity to regulate their mechanical impedance over the range achievable by human limbs, or to replicate the functions that neuromuscular impedance control makes possible. The premise of this chapter is that designing prosthetic limbs capa- ble of replicating the essential functions endowed by impedance controlwould lead to more natural and capable devices. The chapter summarizes current understanding of howhuman limb impedance is regulated, and attempts at replicating the functions afforded by impedance control in prosthetic limbs. It also highlights challenges and possible solutions in each of these areas.