Study on the Friction Nonlinear Control of Force Control System

A nonlinear friction(moment) compensation controller of force (moment) control system is developed. Friction is one of the important factors which affect system performance. Due to the influence of friction nonlinearity to the electro-hydraulic passive force servo system, we develop a nonlinear friction(moment) controller which is applied in force(moment) control system. This controller, which is based on the Lyapunov theorem, doesn´t need precision friction model. It only needs parameters upper bounds. It is a nonlinear friction (moment) compensation controller which is based on non-precision friction model. The simulation results show that compared with PID controller, the controller designed in this paper is better at eliminating the friction(moment) influence. This controller has the use for reference in friction(moment) eliminating of low moment or low velocity force(moment) control system.