A Control Strategy for an Active Alignment Transtibial Prosthesis

This paper presents a control approach for an experimental transtibial prosthesis that can actively realign the residual limb in relation to prosthetic foot during the stance phase of gait. The realignment objective is to inject positive power into the gait cycle while actively reducing the magnitude of the sagittal moment transferred to the residual limb. The altered gait dynamics of this new type of prosthesis require a control approach that coordinates its function with a user’s gait cycle. This paper overviews the mechanical design of the prosthesis development, the proposed finite-state adaptive controller, and presents experimental results for constant cadence walking and adaptation while changing walking speeds.