Inhibitory connections between neural oscillators for a robotic suit

A new synchronization-based control is proposed for a robotic suit which is designed for walking assistance. Neural oscillators are connected to each joint of the robotic suit to synchronize suit´s movement with human user´s movement (outer-synchronization). At the same time, mutual inhibition is incorporated between neural oscillators at each left and right joint of the suit to help to maintain a human-gait-like anti-phase relationship (inner-inhibition). We have developed a 2-DOF robotic suit, which consists of two actuators fixed to the places where the human hip joints are. Each actuator has a built-in torque sensor, which helps to measure the mutual joint torque generated by once there is any difference between the movement of a user and that of the suit. The mutual joint torque is used as input to neural oscillators, which control each actuator of the robotic suit through outer-synchronization with the mutual joint torque and inner-inhibition. The inhibitory weight, used to adjust the inhibitory strength between neural oscillators, is designed properly using series of simulations. We have conducted walking experiments to show the validity of our proposal for walking assistance of the robotic suit with mutual inhibition between neural oscillators.