Wearable Mechanotransduced Tactile Sensor for Haptic Perception

Haptic tactile acuity is an important element for object recognition and manipulation. However, ascribing tactile acuity unto artificial systems is extremely challenging, as it requires active touch exploration involving multidirectional manipulation and sensing. This work reports a skin-inspired liquid-based microfluidic tactile sensor capable of haptic perception. The tactile sensor comprises a uniquely designed elastomeric structure with a microfluidic protrusion. Multidirectional forces on the protrusion result in unique fluid displacement that can be measured electrically. This unique architecture is sensitive enough to discriminate surface changes below 0.5 mm. Our sensor is thin, flexible, and robust, allowing adhesion to skin to directly discriminate surface features, contour changes, and object stiffness. We further show a proof of concept of our wearable tactile sensor for Braille reading, enabling the identification of letters by scanning across standard Braille codes. This technology has potential in enabling haptic perception for users affected by sensory neuropathy or for implementation in medical, social, and assistive robotics.