Design and Characterization of a Textile Electrode System for the Detection of High-Density sEMG

Abstract

Muscle activity monitoring in dynamic conditions is a crucial need in different scenarios, ranging from sport to rehabilitation science and applied physiology. The acquisition of surface electromyographic (sEMG) signals by means of grids of electrodes (High-Density sEMG, HD-sEMG) allows to obtain relevant information on muscle function and recruitment strategies. During dynamic conditions, this possibility demands both a wearable and miniaturized acquisition system and a system of electrodes easy to wear, assuring a stable electrode-skin interface. While recent advancements have been made on the former issue, detection systems specifically designed for dynamic conditions are at best incipient. The aim of this work is to design, characterize, and test a wearable, HD-sEMG detection system based on a textile technology. A 32-electrodes, 15 mm interelectrode distance textile grid was designed and prototyped. The electrical properties of the material constituting the detection system and of the electrode-skin interface were characterized. The quality of sEMG signals was assessed in both static and dynamic contractions. The performance of the textile detection system was comparable to that of conventional systems in terms of stability of the traces, properties of the electrode-skin interface and quality of the collected sEMG signals during quasi-isometric and highly dynamic tasks.

Toward Robust, Adaptiveand Reliable Upper-Limb Motion Estimation Using Machine Learning and Deep Learning–A Survey in Myoelectric Control

“…The motor unit behaviour can provide a novel approach for motion estimation in myoelectric control, and higher accuracy is often expected [143]. However, computational load and energy consumption are substantially increased, and experiment setup is cumbersome [144]. To summarize, sEMG acquisition via different electrodes impacts signal properties, model performances, and system complexity.…”

“…A trade-off between device portability and control accuracy should be considered in real-time applications. Currently, continuous efforts are being made to advance sEMG sensors, such as tattoo ones [145] and textile ones [144], etc. providing considerable potentials to enhance the electrode-skin contact and long-term usability.…”

Sensors for Context-Aware Smart Healthcare: A Security Perspective

“…On the one hand, intramuscular EMG methods are invasive, potentially painful, and not well aligned with smart healthcare solutions. On the other hand, surface EMG methods are non-invasive procedures that only require placing some patch electrodes on the muscle’s skin, facilitating their integration in wearable devices, such as wristbands, armbands, caps or even textiles, to enable long-term monitoring in real-time [ 125 , 126 , 127 , 128 ], tracking tremor and dyskinesia symptoms [ 129 ], preventing falls [ 130 ], recognising gestures and activities [ 131 ], controlling robotic prosthetics [ 132 , 133 , 134 ] and rehabilitation [ 135 , 136 ]. Although more comfortable, the quality of these measurements is affected by the skin’s properties, tissue structure, the adherence of the electrodes to the skin and external electromagnetic interference and noise-filtering techniques are required [ 137 ].…”

A Novel Screen-Printed Textile Interface for High-Density Electromyography Recording

“…In [ 18 ], the authors presented a single screen-printed textile electrode pad, which showed similar electrical properties compared to a hydrogel electrode, despite presenting an overall higher baseline noise. Recently, an electrode grid with multiple pads printed on textile was demonstrated in [ 19 ] and used to record EMG during physical activities, such as cycling, with promising results in terms of signal quality. Regarding the quality of the recording, the critical factor is the good contact between the electrode and the skin, which can be particularly challenging to achieve when using dry solutions [ 20 ].…”

“…Regarding the quality of the recording, the critical factor is the good contact between the electrode and the skin, which can be particularly challenging to achieve when using dry solutions [ 20 ]. For example, to overcome this issue, in [ 19 ], the authors had to apply individual 3D-printed plastic discs on the back of each conductive pad to improve contact between the electrode and the skin. Although functional, this solution complicates electrode production and is, therefore, not optimal for large-scale manufacturing.…”