Decoupling Control Strategy of Magnetic Levitation Planar Motor

There is tight electromagnetic and mechanical coupling among 6-degree of freedom (DOF) motions of magnetic levitation planar motor for photolithography. For decoupling control of the 6-DOF motions, this paper presents the current-controlled model of linear motors as the electromagnetic actuators, the decoupled kinetics model based on the modal forces, and the decoupling control strategy of the planar motor. The 6-DOF kinetics models are successfully decoupled by the modal forces and become simple 2nd order linear systems. The X position servo controller of the prototype is designed. The simulation results show that the controller proposed makes the decoupled X position control with the disired performaces and the control system has good immunity and robust stability.