Tactile Sensor

触觉传感器Essential

A sensor that lets a robot feel contact, measuring pressure distribution, contact location, shear force, and slip.

A tactile sensor measures the information generated when a robot contacts an object, including pressure distribution, contact location, normal and shear force, vibration, and slip; some also sense texture and temperature. Common principles include piezoresistive, capacitive, piezoelectric, and magnetic sensing, as well as vision-based tactile sensing, where a small camera behind a transparent elastomer photographs how the surface deforms at the point of contact — representative examples are GelSight, which originated at MIT, and DIGIT, a low-cost open-source sensor from Facebook AI and collaborators published in 2020. A camera can't see the small patch where a finger meets an object, and it can't measure weight, softness, or friction — exactly the information needed for tasks like twisting off a bottle cap, inserting a cable, or gently squeezing an egg. Tactile data is commonly fed into a policy as tactile images or arrays of individual sensing elements (taxels), alongside vision.

ExampleIn the DIGIT paper, researchers equipped a multi-fingered robotic hand with DIGIT sensors and trained a neural-network controller on the tactile signal to roll a glass marble around in the hand's palm.

Also called: Tactile Sensing
Related: Vision-Based Tactile Sensor · Electronic Skin · GelSight · DIGIT · Slip Detection · Visuo-Tactile Fusion
Sources: Wikipedia: Tactile sensor
arXiv 2005.14679: DIGIT: A Novel Design for a Low-Cost Compact High-Resolution Tactile Sensor