Observer-Based Robust Adaptive Tracking for Uncertain Robot Manipulators with External Force Disturbance Rejection

Abstract

With the rapid growth in technology, the industries are fast-moving from the current automation standing into robotisation to increase productivity and deliver uniform quality. This requirement, in turn, has escalated the demand for robot control schemes. This paper proposes an observer-based robust adaptive tracking control scheme to minimise model uncertainties and external force disturbance effect to control the robot manipulator. No considerations are required for the upper bound of system uncertainties and disturbances in the control design. Plus, the speed of variation and the magnitude of unknown parameters and perturbations are assumed to have no limitations. The proposed control scheme uses an adaptation mechanism for a high gain nonlinear observer along with simplicity and universality properties to ensure robust tracking and make the system follow the desired reference model. Simulation results show that the proposed robust adaptive control scheme achieves boundedness for all the closed-loop signals and convergence of the tracking error.