Impedance and Backstepping Controller of Delta Robot Trajectory Tracking

Abstract

A composite impedance and backstepping control scheme is developed for trajectory tracking of a planar 3-DOF Delta parallel robot. In some scenarios, the moving end of the robot interacts with the rigid environment during working, a force control technique is required for complementation in order to prevent injury from occurring. At first, an impedance controller is designed to produce the desired stiffness and generate new reference trajectory. Then, a backstepping controller takes use of states feedback control strategy is connected in series for position tracking, utilizing Lyapunov stability theory and designing intermediate virtual control parameters, it is shown that the control strategy of the robotic system realizes trajectory tracking asymptotically with exponential convergence rate in case of external force. The simulation results reveal that the proposed controller has a good impedance control effect as well as good trajectory tracking performance.