Electromagnetic Linear Microdrive for Braille Screen: Control and Circuit Test

Abstract

Graphical interfaces based on visual representation and direct manipulation of objects make the adequate use of computers quite difficult for people with reduced sight. A new type of graphical Braille screen is developed. Permanent magnet linear actuator intended for driving a needle in Braille screen has been optimized. The recently developed permanent magnet linear electromagnetic actuator for driving a needle in a Braille screen and the circuit testing method using micro r obots are discussed. Also, a planar and spatial motion tactile display with incorporated electromagnetic linear drives into its links is designed. The optimization is carried out with respect to minimal magnet motive force ensuring required minimum electromagnetic force on the mover. The optimization factors include dimensions of the cores and movable parts under additional constraint for overall dimension of the actuator. Finite element analysis, response surface methodology and design of experiments have been employed for the optimization. The static force characteristics and magnetic field distribution is studied when varying the parameters.