Intelligent sliding mode control for nonlinear friction of high-precision turntable

This paper analyzes the dynamic friction models on the turntable from the engineering practicality. As turntable has the peculiarities such as large tracking range, sudden transferring, high-precision and stability at a low velocity, a control model combining PID Control and Intelligent Sliding Model Control is put forward in this paper. In this model, the switch works according to a threshold. PID Control will be adopted when the tracking error is greater than the threshold and Fuzzy Sliding Model will be used otherwise. The chattering phenomenon is effectively alleviated and the control output is softened by adopting the improved Fuzzy Sliding Model. The genetic algorithm is adopted to dynamically optimize the fuzzy rule of the Fuzzy Sliding Model Control. The global asymptotic stability of the system is proved via Lyapunov´s direct method. The effectiveness and feasibility of the presented control model is proved by the results of simulation and practical tests gained after applying it to the high-precision turntable.