Design concept of a novel EM-array magnetic scanning system for continuous motion control of maximum MFD

This paper presents the design concept and operational principle of a magnetic scanning system for controlling the continuous motion of its maximum magnetic flux density (MFD) in a plane at high speed using an electromagnet (EM) array. Unlike a traditional EM-array where discrete points are controlled for stimulation, actuating or sensing, the synthetized MFD field of the EM array is accurately controlled between adjacent EMs for displaying high-resolution patterns with a relatively small number of EMs. The theory for generating the synthetized MFD that has the Gaussian function properties and three design criteria evaluating its performance as well as the algorithm for implementing it on the 2D EM-array are detailed; both 1D and 2D basic units for line and area scanning are considered. Results agree well with analytically derived exact solutions. Two illustrative application examples are given to demonstrate the applications of an EM array for magnetically reconstructing a cross-road sign pattern, and for generating a moving eddy current field.