CPEP: Contrastive Pose-EMG Pre-training Enhances Gesture Generalization on EMG Signals

Wenhui Cui; Christopher Sandino; Hadi Pouransari; Ran Liu; Juri Minxha; Ellen Zippi; Aman Verma; Anna Sedlackova; Erdrin Azemi; Behrooz Mahasseni

arXiv · 2509.04699

CPEP: Contrastive Pose-EMG Pre-training Enhances Gesture Generalization on EMG Signals

Wenhui Cui·Christopher Sandino·Hadi Pouransari·Ran Liu·Juri Minxha·Ellen Zippi·Aman Verma·Anna Sedlackova·Erdrin Azemi·Behrooz Mahasseni

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Abstract

Hand gesture classification using high-quality structured data such as videos, images, and hand skeletons is a well-explored problem in computer vision. Leveraging low-power, cost-effective biosignals, e.g. surface electromyography (sEMG), allows for continuous gesture prediction on wearables. In this paper, we demonstrate that learning representations from weak-modality data that are aligned with those from structured, high-quality data can improve representation quality and enables zero-shot classification. Specifically, we propose a Contrastive Pose-EMG Pre-training (CPEP) framework to align EMG and pose representations, where we learn an EMG encoder that produces high-quality and pose-informative representations. We assess the gesture classification performance of our model through linear probing and zero-shot setups. Our model outperforms emg2pose benchmark models by up to 21% on in-distribution gesture classification and 72% on unseen (out-of-distribution) gesture classification.

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BibTeX RIS

Wenhui Cui, Christopher Sandino, Hadi Pouransari, Ran Liu, Juri Minxha, Ellen Zippi, Aman Verma, Anna Sedlackova, Erdrin Azemi, Behrooz Mahasseni. 2025-09-04. CPEP: Contrastive Pose-EMG Pre-training Enhances Gesture Generalization on EMG Signals. https://arxiv.org/abs/2509.04699

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