Abstract
Our previous computer simulation study showed that the fuzzy controller based on cycle-to-cycle control would be useful in controlling the swing phase of hemiplegic gate using functional electrical stimulation (FES). However, a simplified musculoskeletal model of a swing leg with the floor reaction force eliminated was used in the previous study. In this paper, a musculoskeletal model consisting of the stance and swing legs with a floor model was developed first. Then, the fuzzy controller for controlling the swing phase was examined using computer simulation of the developed model including the toe off and initial contact. Computer simulation results showed that the fuzzy controller and the stimulation schedule developed in our previous work were adequate, and that modifying the schedule considering the strength of the plantar flexion of the ankle joint would be more effective for improving responses at an early stage of control. A control method based on using electromyograms (EMGs) was also discussed. The fuzzy controller and a previously created EMG-based stimulation schedule, which was unable to control the swing phase, were modified by changing the role of the rectus femoris muscle. The modified fuzzy controller with a new EMG-based stimulation schedule was found to develop the swing phase movement appropriately.
