Robust Adaptive Control Of The Dc Servo System With Friction And Backlash

In this paper, the tracking control for a mechanical system with friction and backlash is considered. Friction and backlash nonlinearities often act on the main obstacles for high precision control. Based on the LuGre friction model and the Backlash model, a robust adaptive control algorithm is developed to compensate for friction and backlash nonlinearities by using backstepping design techniques in the system. A dual observer is adopted to estimate the internal friction stale of LuGre model. A smooth and continuous backlash model is chosen to avoid the noncontinuous property which makes the system control difficult. The boundedness and convergence of the closed-loop system are guaranteed from a Lyapunov stability analysis. Simulation results illustrate the performance of the proposed control scheme.