BeadSight: An Inexpensive Tactile Sensor Using Hydro-Gel Beads

TL;DR

BeadSight is an affordable, replaceable tactile sensor for robots that uses hydro-gel beads and computer vision to accurately detect contact forces and pressure distribution.

Contribution

The paper introduces BeadSight, a novel visuo-tactile sensor that is inexpensive, easily replaceable, and capable of predicting force distributions using neural networks.

Findings

Accurately predicts pressure maps from bead deformation

Effective in detecting contact location and force magnitude

Cost-effective and easily replaceable design

Abstract

In robotic manipulation, tactile sensors are indispensable, especially when dealing with soft objects, objects of varying dimensions, or those out of the robot's direct line of sight. Traditional tactile sensors often grapple with challenges related to cost and durability. To address these issues, our study introduces a novel approach to visuo-tactile sensing with an emphasis on economy and replacablity. Our proposed sensor, BeadSight, uses hydro-gel beads encased in a vinyl bag as an economical, easily replaceable sensing medium. When the sensor makes contact with a surface, the deformation of the hydrogel beads is observed using a rear camera. This observation is then passed through a U-net Neural Network to predict the forces acting on the surface of the bead bag, in the form of a pressure map. Our results show that the sensor can accurately predict these pressure maps, detecting the location and magnitude of forces applied to the surface. These abilities make BeadSight an effective, inexpensive, and easily replaceable tactile sensor, ideal for many robotics applications.