A Hybrid-FES Based Control System for Knee Joint Movement Control.

Area of Science:

• Biomedical Engineering
• Robotics
• Rehabilitation Technology

Background:

• Functional Electrical Stimulation (FES) and rehabilitation robots are key areas in motion control research.
• Controlling knee joint movement with combined FES and active mechanical actuators presents an ongoing challenge.

Purpose of the Study:

• To propose and evaluate a new control algorithm for knee joint motion control.
• To integrate Functional Electrical Stimulation (FES) with a rehabilitation robot for enhanced movement control.

Main Methods:

• An adaptive controller managed motor torque, while a Proportional-Derivative (PD) controller adjusted FES intensity.
• A disturbance observer triggered FES to counteract external disturbances, mitigating muscle fatigue.
• Simulations utilized muscle-joint and servo-motor models with human-recorded knee joint trajectories.

Main Results:

• Simulation studies demonstrated acceptable tracking performance, with computed RMS errors analyzed against the knee motion range.
• The proposed control strategy effectively rejected external disturbances in the simulated environment.
• The system showed the capability to compensate for muscle fatigue induced by FES.

Conclusions:

• The developed control strategy successfully integrates FES and robotic actuation for robust knee joint control.
• The approach demonstrates significant potential for improving rehabilitation outcomes by addressing disturbances and fatigue.
• This research advances the field of assistive and rehabilitative robotics through innovative control solutions.