# ThumbTrak: Recognizing Micro-finger Poses Using a Ring with Proximity Sensing

arXiv: https://arxiv.org/abs/2105.14680 · HTML: https://mlsanity.com/paper/2105.14680/

## Key facts

- Cited by 1 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 31 May 2021.

## Built on by (most cited first, 1 of 1)

- [Exploring Object Status Recognition for Recipe Progress Tracking in Non-Visual Cooking](https://mlsanity.com/paper/2507.03330/) (2025)

## Abstract (arXiv)

ThumbTrak is a novel wearable input device that recognizes 12 micro-finger poses in real-time. Poses are characterized by the thumb touching each of the 12 phalanges on the hand. It uses a thumb-ring, built with a flexible printed circuit board, which hosts nine proximity sensors. Each sensor measures the distance from the thumb to various parts of the palm or other fingers. ThumbTrak uses a support-vector-machine (SVM) model to classify finger poses based on distance measurements in real-time. A user study with ten participants showed that ThumbTrak could recognize 12 micro finger poses with an average accuracy of 93.6%. We also discuss potential opportunities and challenges in applying ThumbTrak in real-world applications.