CHOMP: Multimodal Chewing Side Detection with Earphones

TL;DR

This paper introduces CHOMP, a novel earphone-based system that accurately detects chewing side preference using multimodal sensors and deep learning, enabling continuous, real-world monitoring of jaw function.

Contribution

CHOMP is the first system to use earphones with multimodal sensing and CNNs for reliable, real-time chewing side detection in everyday environments.

Findings

Microphones achieved median F1 scores over 92% in cross-validation.

Sensor fusion improved detection accuracy to over 97%.

System demonstrated robustness under noise interference.

Abstract

Chewing side preference (CSP) has been identified both as a risk factor for temporomandibular disorders (TMD) and behavioral manifestation. Despite TMDs affecting roughly one third of the global population, assessment mainly relies on clinical examinations and self-reports, offering limited insight into everyday jaw function. Continuous CSP monitoring could provide an objective proxy for functional asymmetries. Prior wearable approaches, however, mostly use specialized form factors and demonstrate limited performance. We therefore present CHOMP, the first system for chewing side detection using earphones. Employing OpenEarable 2.0, we collected data from 20 participants with microphones, a bone-conduction microphone, IMU, PPG, and a pressure sensor across eleven foods, five non-chewing activities, and three noise conditions. We apply the Continuous Wavelet Transform to each sensing modality and use the resulting multi-channel scalograms as inputs to CNN-based classifiers. Microphones achieve the strongest single-sensor unit performance, with median F1 scores of 94.5% in leave-one-food-out (LOFO) and 92.6% in leave-one-subject-out (LOSO) cross-validations. Fusing sensing modalities further improves performance to 97.7% for LOFO and 95.4% for LOSO, with additional evaluations under noise interference indicating robust performance. Our results establish earphones as a practical platform for continuous CSP monitoring, enabling clinicians and patients to assess jaw function in everyday life.