Optimized Feature Extraction via Custom Low-Cost sEMG Hardware for Real-Time Myoelectric Interfaces
Received: 13 November 2025 | Revised: 4 December 2025 and 17 December 2025 | Accepted: 24 December 2025 | Online: 5 January 2026
Corresponding author: Ngoc-Khoat Nguyen
Abstract
Surface Electromyography (sEMG) is a widely used modality to infer human motor intent in Human–Machine Interaction (HMI) systems. This study presents a cost-effective, custom-fabricated sEMG acquisition module with three differential channels strategically positioned to capture bioelectric activity from key forearm muscles. The analog front-end is designed with a high-gain amplification stage (2200×) and a bandpass filter spanning 48 to 482 Hz to suppress motion artifacts and ambient noise while preserving relevant myoelectric information. Acquired signals are processed through a lightweight digital pipeline including bandpass and 50 Hz notch filtering, followed by segmentation using a 200 ms sliding window with 50% overlap to balance temporal resolution and computational efficiency. Feature extraction focuses on commonly used time-domain descriptors (MAV, WL, RMS, VAR, and IEMG) and frequency-domain features (MNF and MDF). Experimental evaluation shows that the proposed system achieves a Signal-to-Noise Ratio (SNR) of 17.8–22.5 dB across three channels, while amplitude-based time-domain features (RMS and WL) exhibit less than 5% variability across repeated trials. These results indicate that the proposed hardware–software framework provides stable and reliable feature extraction suitable for real-time embedded applications. The system is therefore well-suited for wearable HMI scenarios such as myoelectric prostheses, robotic exoskeletons, and assistive robotic devices requiring low latency and low computational complexity.
Keywords:
sEMG, custom-fabricated sEMG sensor, biomedical signal processing, feature extractionDownloads
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Copyright (c) 2026 Thi-Mai-Phuong Dao, Van-Kien Nguyen, Ngoc-Khoat Nguyen, Loc Le, Tien-Dung Nguyen, Tri Nguyen, Thi-Duyen Bui, Duy-Trung Nguyen, Huu-Thang Nguyen
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