Friction compensation for a robust, low order H∞-optimal position control of a multi-mass system

Controlling a multi-mass system is a common problem in industrial automation. Varying or unknown parameters, especially friction, make the control problem more difficult. A powerful tool to control systems with uncertain parameters is a robust H_infin-controller. Furthermore, high static friction often still causes problems like stick slip effects. Therefore, friction compensation is needed in addition to a robust controller. This paper will present a simple yet robust friction compensation used in tandem with a robust H_infin-controller. Measurements will complete the paper.