A Piezoresistive Sensor to Measure Muscle Contraction and Mechanomyography


Measurement of muscle contraction is mainly achieved through electromyography (EMG) and is an area of interest for many biomedical applications, including prosthesis control and human machine interface. However, EMG has some drawbacks, and there are also alternative methods for measuring muscle activity, such as by monitoring the mechanical variations that occur during contraction. In this study, a new, simple, non-invasive sensor based on a force-sensitive resistor (FSR) which is able to measure muscle contraction is presented. The sensor, applied on the skin through a rigid dome, senses the mechanical force exerted by the underlying contracting muscles. Although FSR creep causes output drift, it was found that appropriate FSR conditioning reduces the drift by fixing the voltage across the FSR and provides voltage output proportional to force. In addition to the larger contraction signal, the sensor was able to detect the mechanomyogram (MMG), i.e., the little vibrations which occur during muscle contraction. The frequency response of the FSR sensor was found to be large enough to correctly measure the MMG. Simultaneous recordings from flexor carpi ulnaris showed a high correlation (Pearson's r > 0.9) between the FSR output and the EMG linear envelope. Preliminary validation tests on healthy subjects showed the ability of the FSR sensor, used instead of the EMG, to proportionally control a hand prosthesis, achieving comparable performances.

Publication DOI: https://doi.org/10.3390/s18082553
Divisions: College of Health & Life Sciences
College of Health & Life Sciences > School of Optometry > Optometry & Vision Science Research Group (OVSRG)
Additional Information: This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
Publication ISSN: 1424-8220
Full Text Link:
Related URLs: http://www.mdpi ... -8220/18/8/2553 (Publisher URL)
PURE Output Type: Article
Published Date: 2018-08-07
Accepted Date: 2018-08-01
Authors: Esposito, Daniele
Andreozzi, Emilio
Fratini, Antonio (ORCID Profile 0000-0001-8894-461X)
Gargiulo, Gaetano D.
Savino, Sergio
Niola, Vicenzo
Bifulco, Paolo



Version: Published Version

License: Creative Commons Attribution

| Preview

Export / Share Citation


Additional statistics for this record