A digital tactile actuator array with normal and shear contact force controllability for refreshable Braille display application

This paper presents a novel digital controlled tactile actuator array driven with ionic polymer metal composite (IPMC) actuators. A 5 × 5 PDMS bump array can be manipulated to touch human sensory receptors (e.g. on the fingertips) with different force levels (Fig. 1). Each element, a bump with an IPMC actuator pair underneath, can be controlled individually through delivering different electrical signals to each actuator of the pair. The contact between the fingertip and the bump on top of the actuator pair can then produce the motion in normal and shear modes to allow the fingertips receiving different feeling signals. The fast response of bump array to perform up-and-down and swing motions makes the actuator array very suitable for refreshable Braille display application.