Online Modeling of Piezoelectric Actuators Based on Non-smooth Sandwich Model with hysteresis

In order to accurately describe the high-frequency motion characteristics of the Piezoelectric Actuators (PEA), an online modeling method is proposed in this paper. In this identification scheme, a nonlinear discrete hysteretic operator is firstly introduced to handle the non-smoothness and multi-value mapping of the hysteresis. Then, the key term separation technique is employed to obtain a special form of the sandwich model, which its expression is linearized in parameters. Finally, a Recursive General Identification Algorithm (RGIA) is applied to the estimation of the parameters of the sandwich model. The experimental results obtained by implementing the proposed identification scheme are also presented in this paper. It can satisfy the design requirement of the adaptive control the piezoelectric ultra-precision motion systems.