A Flux-Density-Based Electromagnetic Servo System for Real-Time Magnetic Servoing/Tracking

The goal of this paper is to develop an electromagnetic servo system for two kinds of multiaxis motion control, namely magnetic servoing and magnetic tracking. Based on the proposed space vector expression that is a function of magnetic flux density for estimating the relative position from a magnet to a Hall probe, the magnetic servoing can achieve a contouring control with respect to a fixed magnet, and the magnetic tracking can track a moving magnet. The proposed flux-density-based feedback control is a fully closed-loop scheme, which involves an inner position control loop and an outer magnetic control loop. Experiments are presented to demonstrate the validity of the space vector expression in terms of flux density and the feasibility of the electromagnetic servo system using flux density feedback control.