Design and simulation of load dynamic compensation controller based on dynamic model for upper limb exoskeleton robot

Abstract

In this paper, we propose a dynamic load compensation controller based on two-degree-of-freedom upper limb exoskeleton dynamics model to control the upper limb exoskeleton robot follow operator's arm's movement. In this paper, the main function of the upper limb exoskeleton robot is to lift a certain weight of load and follow operator's arm's movement. Since the weight of the load is unknown when establishing the dynamic model of the upper limb exoskeleton, it is necessary for the upper limb exoskeleton's controller to conduct corresponding feedback compensation making the upper limb exoskeleton to follow the operator's arm movement better when lifting different weights of load. The practice is to install a six-dimensional force sensor between the load and the operating arm, in the dynamic movement of the arm, the controller compensate for the corresponding torque in each joint timely. At the end of the paper, we use the Matlab Simulink component to simulate the improved dynamic load compensation controller. The experimental results show that the controller with dynamic load compensation can control the upper limb exoskeleton operating arm follow operator's arm's movement with faster speed and smaller error than the controller without dynamic load compensation.