Humanoid finger tactile array senses grip contact beyond fingertips
Tactile Sensing Array for Multi-Phalanx Sensing in Humanoid Hands
RoboticsEmerging Technologies
Summary
Robots with human-like hands need to feel touches not just on their fingertips but along their fingers to grab objects properly. Vision alone can’t tell if the fingers are touching something when they block the camera’s view. The authors made a low-cost sensor using materials like Velostat that can detect touch across different parts of a robot finger. Their design senses different shapes pressing on the fingertip and registers contact on several finger parts during a grip. They also improved the sensor’s speed in letting go of touch by changing its shape, and suggest software tricks could fix remaining delays.
What this means in practice
- •For robotics engineers: Add tactile sensing along robot fingers to improve object grasping and manipulation under occluded vision.
- •For prosthetics developers: Enhance artificial hands with low-cost multi-phalanx tactile arrays for better touch feedback during object handling.
Authors
Neel Adwani, Muhaiminul Islam Akash, Rituja Bhattacharya, Cong Wang
Abstract
Humanoid hands require tactile feedback across the whole finger, not just the fingertip, to grasp and manipulate objects properly. Vision and proprioception alone cannot reliably provide this information, particularly when the hand's own fingers occlude the camera's view of the grasp. We present a low-cost tactile array for a humanoid finger, made from Velostat and conductive tape. The fingertip carries seven contact points including a 2x3 matrix wrapped across its front, left, and right faces, and a separate contact point at the tip. The proximal and middle phalanges each carry a single front-facing contact line. We measure the sensor's hysteresis and recovery time after release, through repeated loading and press-release tests. We also test a compliant, 3D-printed contact structure with a gap and a bump, inspired by similar designs in prior work, and show it cuts recovery time by 74% compared to a flush-contact baseline. We then show the sensor can produce distinct activation patterns for different contact geometries (flat, edge, corner) at the fingertip, and that it registers contact across all three phalanges during a grip. Finally, we discuss the limits of our fabrication changes and point to software-based compensation as a promising way to more directly fix the remaining hysteresis in the future.