Intelligent control of piezoelectric actuators

An intelligent tracking control architecture is proposed for a class of continuous-time nonlinear dynamic systems actuated by piezoelectric actuators. Generally, hysteresis nonlinearity exists in the piezoelectric actuator, which may cause undesirable inaccuracy. Based on solutions of a general hysteresis model, an approximation function is introduced to compensate for effects of the hysteresis nonlinearities. This approximation function is implemented by fuzzy logic method, which is expressed as a series expansion of basis functions. Combining this approximation function with adaptive control techniques, an intelligent control algorithm is developed. As a result, global asymptotic stability of the system is established in the Lyapunov sense. Simulation results are included to demonstrate the control performance.