Development of a braille display using piezoelectric linear motors

The refreshable braille displays for visually impaired people should be portable and capable of real-time display. To this end, the actuators used to move braille dots should be small and lightweight. So far various actuators such as solenoids, piezoelectric materials, electroactive polymers have been suggested, but these actuators have not been very successful for various reasons. In this research, piezoelectric linear motors were adopted for this purpose. These actuators can provides the response time fast enough to offer real-time display, and are small and lightweight enough to be employed for a portable device. In this paper, the details of the proposed braille cell consisting of six piezoelectric linear motors are discussed. The electrical circuit to drive the motors is also introduced. Various tests have been conducted for seven visually impaired people. These tests for the prototype braille display system show that it can deliver the braille information which can be well recognized by visually impaired people.