A high-precision, magnetically levitated positioning stage: toward contactless actuation for industrial manufacturing

In this paper, the feasibility of using iron-cored permanent magnet linear synchronous motors (PMLSM) to develop microsteppers with multiple DOFs is demonstrated. To do this, the accuracy of the mathematical model of the longitudinal and normal forces generated by one PMLSM as well as the performance of a nonlinear feedback linearization controller are investigated. Demonstration of several PMLSMs together can control three DOFs. In both experimental setups, linear guides are used to constrain the motion to be purely translational. Linear guides entail friction, which is undesirable in the photolithography process. Future research involves eliminating linear guides and controlling six DOFs (translations and rotations of the platform).