Piezoelectric friction actuating mechanism is chosen to construct long traveling range sub-micro X-Y positioning table. LuGre friction model is employed to simulate the friction dynamics of this positioning mechanism. The optimization scheme of Matlab toolbox is adopted to search the optimal friction model parameters. However, this piezoelectric actuating system has obvious nonlinear and time-varying dead-zone offset control voltage due to the static friction and preload. The estimated LuGre dynamic model is still not accurate enough for model-based precision control design. Hence, the adaptive sliding mode control (SMC) with robust behavior is employed to design the nonlinear controller for this piezoelectric friction actuating mechanism. The Laypunov-like design strategy is adopted to achieve the system stability criterion. The dynamic experimental results of the proposed nonlinear controllers are compared with that of a model-based PID controller, too.
Theoretical Analysis of Friction Compensation Using Sliding Mode Control
