A uSkin Fingertip with a Tactile Fingernail for Contact-Rich Dexterous Manipulation

Steven Oh, Satoshi Funabashi, Hiroki Niimi, Tai Yamada, Kazutaka Omori, Pranav Ponnivalavan, Tetsuya Ogata, Shigeki SUGANO

Keywords: Dexterous manipulation, tactile sensing

TL;DR: We add a sensorized fingernail to a uSkin fingertip and demonstrate through force/localization evaluation and card-flipping imitation learning that fingernail tactile sensing is effective for contact-rich dexterous manipulation.

Abstract:

We present a tactile robotic fingertip that extends a conventional uSkin fingertip with a sensorized fingernail. While soft fingertip tactile sensing is effective for grasping and contact monitoring, fingernails enable interactions that require edge engagement, thin-gap access, scraping, and concentrated force application. To extend tactile sensing to this regime, our design adds Hall-effect-based distributed tactile sensing beneath a rigid fingernail while preserving dense tactile sensing on the compliant finger pad. We evaluate the proposed design through contact force and localization experiments across multiple interaction directions, showing that distributed nail sensing improves estimation performance over reduced sensing configurations.
We further demonstrate its benefit in an imitation-learning card-manipulation task and several real-world nail-assisted manipulation behaviors.
These results suggest that sensorized fingernails can expand the capabilities of tactile robotic hands beyond conventional fingertip-pad interactions.

Submission Number: 23