Soft Auxetic Fingertip (SAF) for Shape-Adaptive and Stable Grasping
Peiyu Ma, Zhengquan Shen, Yukun Ge, Thrishantha Nanayakkara
Abstract
This letter presents a soft auxetic fingertip (SAF) that decouples shape adaptability from payload ability by separating rigid support from compliant conformity. A stiff outer frame carries loads while auxetic array provides passive conformity and enlarges the contact area, distal tips improve grasping of flat and thin objects. The fingertip is fabricated by 3D printing conductive thermoplastic polyurethane (TPU). Based on its piezoresistive effect, the soft auxetic layer is used as a mechanical filter to enable contact and slip detection and to drive a grip-force compensation strategy. Under identical input torques, SAF achieves a 10.66%–151.72% payload improvement over the FinRay baseline across eight objects. Combined with slip detection based on resistance signal and grip-force compensation, it achieves a 89.29% success rate in pick-and-place tests on 28 tools and food items.
BibTeX
@inproceedings{ral2026_softauxeticfinge,
title = {Soft Auxetic Fingertip (SAF) for Shape-Adaptive and Stable Grasping},
author = {Peiyu Ma and Zhengquan Shen and Yukun Ge and Thrishantha Nanayakkara},
booktitle = {RA-L 2026},
year = {2026}
}