Modeling and Simulation Analysis of 6-DOF Magnetic Levitation Vibration Isolation Platform

Magnetic levitation gravity compensator (MLGC) with cooperative Lorentz force motors (LFM) is the optimal solution to solve the vibration isolation problem of nanoscale positioning systems. In order to improve the stability and the control quality of active vibration isolation systems, it is necessary to build accurate model of 6 -DOF magnetic levitation vibration isolation platform (MLVIP). First, this paper introduces the basic structure and working principle of MLVIP and core components, such as LFM and MLGC. Second, the force characteristics model of novel LFM and MLGC proposed in this paper are analyzed. Third, the dynamic model of single DOF MLVIP considering inconstant thrust coefficient of LFM and stiffness of MLGC is established. A nd a three loops PID controller including position loop, acceleration loop and current loop is designed. What is more, vibration isolation performance is comparatively analyzed under active and passive modes at different frequencies by MATLAB SIMULINK. It is proved that active isolation method has better isolation performance in both low and intermediate frequency bands. At last, the force and torque of LFMs are decoupled and dynamic model of 6-DOF MLVIP is established.