Decoupling Control for a Magnetic Suspension Stage

A novel planar motion stage superposed with two magnetic suspension vehicles has been presented in this paper. The stage is a micro-electromechanical device which can widely be used in semiconductor manufacturing, printed circuit board processing, micro-assembling system, etc. The kinematics and dynamic models of the stage show that it is a highly coupled system. The decoupled control of the system is presented by utilizing the symmetry of the geometric configuration and space coordinates transformation techniques to eliminate the redundancy of electromagnetic force control. Then, each one of the five motion states becomes a SISO linear sub-system and the linear control theory can be used to design the feedback controller. Simulation results demonstrate that the proposed control scheme has better dynamic and static characteristics.