A Wearable Tactile Sensor Array for Large Area Remote Vibration Sensing in the Hand

Tactile sensing is essential for skilled manipulation and object perception. Existing sensing devices cannot capture the full range of tactile information in the naturally behaving hand, and are unable to match human abilities of perception and action. Human touch sensing is mediated via contact-generated mechanical signals in the skin. Time varying contacts elicit propagating mechanical waves that are captured via numerous vibration-sensitive neurons distributed throughout the hand, yielding a wealth of sensory information. Little engineering attention has been given to this important biological sensing system. Inspired by human sensing abilities, we present a wearable system based on a 126 channel sensor array capable of capturing high resolution tactile signals throughout the hand during natural manual activities. It employs a network of miniature three-axis sensors mounted on a flexible circuit whose geometry is adapted to the anatomy of the hand, allowing tactile data to be captured during natural manual interactions. Each sensor possesses a frequency bandwidth overlapping the entire human tactile frequency range. Data is acquired in real time via a custom FPGA and an I2C network. We also present physiologically informed signal processing methods for reconstructing whole hand tactile signals. We report experiments that demonstrate the utility of this system for collecting rich tactile signals during manual interactions.