Disturbance Observer-Based Robust Control of A Flexible Joint Manipulator in The Presence of Unknown Disturbance

This study proposed a State feedback controller (SFC) with a Disturbance observer (DO) for a flexible joint robotic arm under disturbances. The dynamic model of flexible joint robotic arms has vibrations. Due to this system response changes while the movement of a robotic arm, which results in the position of the tip of a link is not set in a proper place. since there is a need to control the vibration of a robotic arm. The design of a traditional controller is capable only of state estimation and evaluations of internal disturbance. Since there is a need for a robust controller and this is achieved by designing the SFC + DO. Which determines the state vector, uncertainties like modeling error, parameter variation, external disturbances, etc. The proposed approach proves closed-loop stability. Simulation results show the efficacy of SFC + DO in the performance of position tracking, estimating states, and uncertainties.