When Giant magnetostrictive micro-displacement actuator(GMA) was implemented in the precision or super precision finishing occasion

The system was affected by the external load

The dynamics effect lead to the eddy current in the components and the output displacement of system exist hysterisis. Employing the linear piezomagnetism equation

mechanical electrical transformation equation and impedance analysis method to set up the vector impedance model of the system. The model divides the system vector impedance into two sections

mechanical admittance and electrical impedance. Considering the external load influence and define the coefficient of pizeomagnetism as a constant complex variable to simulate the displacement hystersis; in the solved the magnetization in the magnetostrictive material added eddy current term to simulated the system nonlinear characteristics. the sum of two sections were the system vector impedance. As indicated in the comparison between experimental and model data.

the measured vector impedance and the model data error was about 7 percent in magnitude and 7.7 percent in phase. the results show us the model can be simulated the system impedance characteristics under the precision occasion

and it can guide the design

control and the performance optimize of the GMA system.