A vibro-tactile system for image contour display

This paper presents the design and testing of an image contour display system with vibrotactile array. The tactile image display system is attached on the user´s back. It produces non-visual image and permits subjects to determine the position, size, shape of visible objects through vibration stimulus. The system comprises three parts: 1) a USB camera; 2) 48 (6×8) vibrating motors; 3) ARM micro-controlled system. Image is captured with the camera and the 2D contour is extracted and transformed into vibrotactile stimulus with a “contour following” (time-spatial dynamic coding) pattern. With this system subjects could identify the shape of object without special training; meanwhile fewer vibrotactile actuators are adopted. Preliminary experiments were carried out and the results demonstrated that the prototype was satisfactory and efficient for the visually impaired in seeing aid and environment perception.