Bilateral Control of Human Upper Limbs Using Functional Electrical Stimulation Based on Dynamic Model Approximation

Bilateral control is a remote-control technique that can transmit the reaction force received by a slave as feedback to its master. However, it poses several problems; hence, bilateral control using functional electrical stimulation (FES) has been proposed as a solution. Generally, in bilateral control, position synchronization and establishing the force action-reaction are considered the control targets for an acceptable force sense transmission. In this study, bilateral control using FES based on a dynamic model is proposed to achieve position synchronization and force action-reaction. The approximation of the relationship between the stimulus value and the exerted torque by the dynamic model is expected to simplify the creation of inverse models and improve the force control performance. The results obtained through comparison with other methods indicated that the proposed method reduced the angle and torque tracking errors between the master and slave. The results also revealed that the proposed bilateral control system achieved highly accurate position synchronization and force action-reaction in bilateral control using FES.