Planar haptics: A wireless haptic glove using interwoven nitinol actuators for accelerated feedback response

Abstract

Modern haptic devices typically employ motors for feedback which are reliable but bulky, limiting the user’s range of motion and mobility. Significantly lighter Shape Memory Alloys (SMAs) such as nitinols present a promising alternative. However, they suffer from thermal and electrical constraints and require thermal management. This paper presents an innovative nitinol-based haptic glove using interwoven actuators for accelerated feedback response. A formal psychophysical evaluation explores the perception of kinesthetic fingertip force feedback through nitinol activation based on current amplitude. The haptic glove presented improves the interval needed for activating the actuators. It places the actuators on the bottom of the fingers to provide more accurate directional force feedback while taking advantage of nitinol’s low profile to significantly reduce the actuator’s footprint. It also introduces a flexible printed circuit design that replaces conventional cumbersome cabling. This significantly reduces the device’s volume, resulting in a light planar haptic device that supports flat components. The actuators embedded in the glove are controlled via a microprocessor communicating with a Virtual Reality Head Mounted Display. Our results show that there is a visible sensitivity gradient across fingers of the hand.