Diamagnetically levitating motor with improved optical feedback reference tracking

Abstract

This paper describes the conceptual principle, operation and control of a low friction, low maintenance pow er delivering motor using a diamagnetically stabilized levitating rotor. The planar rotor described in this paper rotates due to nine electromagnets evenly spaced around the rotor. An optical encoder feedback system is designed and fabricated that controls the frequency of the levitating rotor. An improved driving circuit allows current to flow through one phase at a time, which produces a magnetic field strong enough to spin the rotor. Experiments suggest that the optical encoder feedback control system can do reference tracking on the levitating rotor system. The designed control algorithm can drive the rotor to specified reference frequencies up to 1.3 Hz using the optical encoder measurements. An improved control algorithm and an actuator system with higher switching speed are implemented to observe faster system response.