Transforming a Monolithic Sheet of Nitinol into a Passive Reconfigurable Tactile Pixel Array Display at Braille Resolution

Shape changing materials create a unique opportunity to design reconfigurable tactile display actuators. In this paper, we present a method that transforms a single thin monolithic sheet of Nitinol into a passive reconfigurable tactile pixel array at Braille resolution. We have designed a 27x27 tactile pixel array in which each pixel can be selectively actuated with an external source of heat. The pixels rise 0.4mm vertically with a peak blocked force of 0.28kg and have an average blocked force of 0.23kg at room temperature. After cooling, the pixels can be mechanically reconfigured back to their flat state for repeatable actuation. We demonstrate this actuator’s interactive capabilities through a novel erasable tactile drawing interface.