μTouch: Enabling Accurate, Lightweight Self-Touch Sensing with Passive Magnets

Abstract

Self-touch gestures — touching one's own face, head, or body — are natural, expressive, and privacy-preserving interaction modalities. Yet detecting them accurately remains difficult: wrist-worn devices miss subtle movements, cameras raise privacy concerns, and acoustic sensors struggle with soft contact.

μTouch introduces a novel self-touch sensing platform built on passive magnets — small, wearable, and infrastructure-free. By tracking the relative magnetic field between magnets placed on different body parts, μTouch recognizes a rich vocabulary of nuanced self-touch gestures including facial touches and subtle finger scratches, without any active power source on the sensing element.

Key Insights

• Passive magnets require no battery on the sensing tag — only the receiver needs power.
• Magnetic fields pass through clothing and skin, enabling occluded and subtle touch detection.
• A lightweight signal processing pipeline enables real-time recognition on commodity hardware.

BibTeX

@inproceedings{wang2026microtouch,
  title     = {μTouch: Enabling Accurate, Lightweight Self-Touch Sensing with Passive Magnets},
  author    = {Wang, Siyuan and Li, Ke and Huang, Jingyuan and Wang, Jike and Zhang, Cheng and Sample, Alanson and Chen, Dongyao},
  booktitle = {Proceedings of the IEEE International Conference on Pervasive Computing and Communications (PerCom)},
  year      = {2026}
}