Electromagnetic Microactuator-Array Based Virtual Tactile Display

This paper describes the development and evaluation of a novel tactile display assembled from a 4 by 5 array of electromagnetic, voice-coil type micro-actuators. Each actuator is separately controlled and operates at the optimum human tactile recognition vibrating frequency and amplitude as vibrotactile actuators (tactors). As a preprogrammed, meaningful sequence of micro-actuators is actuated, the user recognizes the vibro-tactile pattern on his/her fingertip and identifies it as a single alpha-numeric character. Human subject studies have been conducted where the actuators are vibrating vertically between their resting position and the surface of the involved fingertip in a predefined sequence, which creates the tactile perception of continuous curves. The efficiency analysis by which these curves are identified as characteristic shapes by the subjects shows an average of over 70 % recognition performance.