A Basic Study on MPC with a Simple Model for FES: Computer Simulation Tests in Wrist Joint Control

Model Predictive Control (MPC) is an optimal control technique where control action is obtained by minimizing the objective (cost) function subject to the model equation of the plant. In this basic study, the feasibility of MPC for Functional Electrical Stimulation (FES) using a simple identified model was investigated. The MPC-FES controller was examined in controlling the 1-DOF movement of the wrist joint through computer simulation. The dynamic models of the wrist joint movements were developed by using the step response of an electrically stimulated musculoskeletal system for each subject. The average model of the step responses of several subjects has also been used to test the feasibility of the MPC for FES. Computer simulation tests showed that the MPC-FES controller with a simple model based on step response of each subject as well as the average model was able to follow the desired movement trajectory with small error.