A robust end effector tracking controller formulation for robot manipulators actuated via brushless DC motors with uncertainties

Abstract

A robust controller formulation for the precise end effector tracking of robot manipulators having uncertainties throughout its entire mechanical and actuator subsystems is presented. The formulated robust controller achieves practical end effector tracking, even in the presence of uncertainties in the kinematic and dynamic parameters of the mechanical subsystem and the electrical parameters of the actuator subsystem. Specifically, a robust backstepping type controller formulation that makes use of the nominal values of the system parameters is designed to ensure an exponentially convergent, practical end effector tracking result. The stability and global convergence of the controller formulation are ensured via Lyapunov type arguments and extensive experimental studies conducted on custom-built planar robotic manipulator demonstrate the feasibility of the proposed method.