Saved in:
Bibliographic Details
Main Authors: Yeon, Taeyoung, Xu, Vasco, Hoffmann, Henry, Ahuja, Karan
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2509.04736
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912571712339968
author Yeon, Taeyoung
Xu, Vasco
Hoffmann, Henry
Ahuja, Karan
author_facet Yeon, Taeyoung
Xu, Vasco
Hoffmann, Henry
Ahuja, Karan
contents Despite advances in practical and multimodal fine-grained Human Activity Recognition (HAR), a system that runs entirely on smartwatches in unconstrained environments remains elusive. We present WatchHAR, an audio and inertial-based HAR system that operates fully on smartwatches, addressing privacy and latency issues associated with external data processing. By optimizing each component of the pipeline, WatchHAR achieves compounding performance gains. We introduce a novel architecture that unifies sensor data preprocessing and inference into an end-to-end trainable module, achieving 5x faster processing while maintaining over 90% accuracy across more than 25 activity classes. WatchHAR outperforms state-of-the-art models for event detection and activity classification while running directly on the smartwatch, achieving 9.3 ms processing time for activity event detection and 11.8 ms for multimodal activity classification. This research advances on-device activity recognition, realizing smartwatches' potential as standalone, privacy-aware, and minimally-invasive continuous activity tracking devices.
format Preprint
id arxiv_https___arxiv_org_abs_2509_04736
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle WatchHAR: Real-time On-device Human Activity Recognition System for Smartwatches
Yeon, Taeyoung
Xu, Vasco
Hoffmann, Henry
Ahuja, Karan
Computer Vision and Pattern Recognition
I.2.10; H.5.2
Despite advances in practical and multimodal fine-grained Human Activity Recognition (HAR), a system that runs entirely on smartwatches in unconstrained environments remains elusive. We present WatchHAR, an audio and inertial-based HAR system that operates fully on smartwatches, addressing privacy and latency issues associated with external data processing. By optimizing each component of the pipeline, WatchHAR achieves compounding performance gains. We introduce a novel architecture that unifies sensor data preprocessing and inference into an end-to-end trainable module, achieving 5x faster processing while maintaining over 90% accuracy across more than 25 activity classes. WatchHAR outperforms state-of-the-art models for event detection and activity classification while running directly on the smartwatch, achieving 9.3 ms processing time for activity event detection and 11.8 ms for multimodal activity classification. This research advances on-device activity recognition, realizing smartwatches' potential as standalone, privacy-aware, and minimally-invasive continuous activity tracking devices.
title WatchHAR: Real-time On-device Human Activity Recognition System for Smartwatches
topic Computer Vision and Pattern Recognition
I.2.10; H.5.2
url https://arxiv.org/abs/2509.04736