The torque control system of exoskeleton ExoArm 7-DOF used in bilateral teleoperation system

The upper limb exoskeleton presented in this paper is a device that enables the operator to control machines with force feedback. This is only feasible if the operator does not feel the weight of the device. The operator should only feel the resistance coming from the controlled device i.e. loading crane. The exoskeleton’s control system should generate the motion of the exoskeleton so that the device follows the movement of the operator’s upper limb. The paper presents the method of connection of master and slave control systems in bilateral teleoperation. The developed control algorithm allows for implementation of two control methods: position control method and torque control method, obtaining the possibility of hybrid positional-force control. The torque value control algorithm can be used to maintain the exoskeleton’s force of interaction with the operator at a given level. Maintaining the torque at before set level enables the implementation of force feedback while controlling the position of the slave device. Experimental tests of the described control system were carried out on the exoskeleton’s joint responsible for the movement of the operator’s elbow joint.