On Virtual Force Control of Exoskeleton Suit

When the exoskeleton suit moves,it is hard to get the control instructions.In order to solve this problem,a reference trajectory estimation method for the exoskeleton suit is proposed which can be realized by installing some multiaxis force/torque sensors between the pilot and the exoskeleton suit.A virtual force control method is proposed to control the exoskeleton suit to follow the pilot's locomotion and to minimize the human-machine interaction force,which means the exoskeleton suit assisting the pilot to take heavy load.This method first generates the joint control torque of exoskeleton suit in joint space by the measurement information of the force/torque sensors,and then generates the virtual control force in task space to enable the exoskeleton suit to follow the pilot's motion.Stability of the presented method is proved and simulation result is given.The simulation result shows the designed controller can control the exoskeleton suit tracking the pilot's motion as well as decreasing the human-machine interaction force effectively.