Development of an Electromagnetic Haptic Display System for the Visually Impaired*

Assistive devices for the visually impaired have the purpose of reducing the stress of vision loss, and to support their more constrained lifestyles. Blindness prevents the viewing of visuals media, but the use of tactile non-visual haptic displays will reduce this limitation and improve the quality of life of these people. A 10x15-resolution electromagnetic levitation-based tactile haptic display system is developed in this paper. Series of images from a camera attached to eyeglasses are processed and converted to 10x15-resolution gray-scale images before being sent to a set of controllers that use voltage-based feedback control to raise 150 taxels of the haptic display to the heights of the corresponding gray values. A locking mechanism allows the users to press their hands on the haptic display without changing the image pattern for 5 seconds. Practical tests indicated that the developed haptic display could display low-resolution binary, grayscale and color images with the taxel displacements at millimeter accuracy.