Magnet Levitation and Trajectory Following Motion Control Using a Planar Array of Cylindrical Coils

Abstract

We have formulated and implemented a control system for levitation and motion control of a disk magnet using a planar array of electromagnetic coils and an optical localizer to provide real time position feedback. The significance of this work is that this is the first magnetic levitation system which controls the orientation and position of a levitated body throughout a workspace volume whose dimensions are multiples of those of the levitated body in all directions. Furthermore, the horizontal range of motion can be extended indefinitely by adding more coils to the planar array. The potential applications of this levitation system include any robotic manipulation and positioning tasks such as camera and antenna pointing, materials handling and processing, and haptic interaction. Analysis methods, implementation details, and experimental results are given for our current system with a 37.5 mm diameter and 12.5 mm height magnet and 10 actuator coils, providing an 80×60×30 mm range of motion.