Nonlinear modeling of piezoelectric actuator based on SVR

The establishment of non-linear model of piezoelectric actuator is a key link of the nano-scale micro-displacement measurement and control. Due to the inherent nonlinearity and the influence of load pressure, piezoelectric actuator always causes position error in the open-loop system and instability in the closed-loop system. Based on the experiment of creep characteristics, the effect of driven voltage and load pressure on piezoelectric actuator output displacement has been researched in this paper. A non-linear model of piezoelectric actuator using orthogonal test and support vector regression (SVR) has been set up. And modeling experiments have been carried out. The experiments show that the predicted values agree well with the experimental results. The process of modeling is explicit, and the computation is simple.