Feedback linearizing controller for a flexible single-link arm under gravity and joint friction

Abstract

This paper presents a control scheme for a flexible single-link arm moving under gravity. The purpose of this controller is the precise positioning of the arm tip in presence of link vibrations and joint friction. In order to achieve this, a two nested loop control is used: The inner loop is responsible for the motor positioning, and the outer loop suppresses the vibrations in the arm structure. On the inner loop design, a linear algebraic controller is considered. On the outer loop, an input/state linearization control is chosen. Simulation results are presented to demonstrate the performance of the controller.