A novel control scheme incorporating voluntary contributions for the closed-loop control of neuroprostheses

Closed-loop control of neural prostheses promises to improve the performance, benefits, and acceptance of FES systems. In applications for the lower extremities the patient´s arms are essential for maintaining balance and load support during ITS-generated movements, Hence, their influence must be considered in the control strategy. Conflicts between the voluntary upper body effort and the artificial control system for the lower body is to be avoided. In this paper a novel approach is presented in which the desired movement is provided as a path in the joint angle space. The main advantage of this control strategy is the capability to respond appropriately to the contributions of the patient´s upper body. The feasibility of the approach presented is demonstrated by computer simulations of a sit-to-stand transfer