6 DOF Magnetically Suspended and Propelled Mirror

An actively controlled magnetically levitated mirror with 6 degrees of freedom (DOF) is presented. This mirror is to be used in a measurement system based on laser interferometry. A novel magnetic topology has been developed for actuating all six DOFs of the mirror. This topology almost completely decouples the different degrees of freedom. The forces and torques are independent of the rotor angle and are proportional to the applied currents. This simplifies controller design consider- ably. A contactless differential capacitive position sen- sor system has been designed to measure the position and orientation of the mirror. This capacitive sen- sor system is incorporated in the magnetic actuator topology.