Convex Hull Area in Triaxial Mechanomyography during Functional Electrical Stimulation

Guilherme N. Nogueira-Neto, Eddy Krueger, Eduardo M. Scheeren, Vera L. S. N. Button, Percy Nohama

2014

Abstract

This study employed the convex hull in the analysis of triaxial mechanomyography (MMG) to determine hull area variations along prolonged muscle contractions elicited by functional electrical stimulation (FES). Closed-loop FES systems may need real-time adjustments in control parameters. Such systems may need to process small sample sets. The convex hull area can be applied to small sample sets and it does not suffer with non-stationarities. The MMG sensor used a triaxial accelerometer and the acquired samples were projected onto all planes. The hull determined the smallest convex polygon surrounding all points and its area was computed. Four spinal cord injured volunteers participated in the experiment. The quadriceps femoral muscle was stimulated in order to cause a full knee extension. FES parameters: 1 kHz pulse frequency and a 20 Hz burst frequency. Adjustments in the stimuli amplitude were controlled by a technician to sustain the extension. The results showed that the convex hull area decreased over time. Since the polygons are related to MMG amplitude, decreasing areas were related to muscle fatigue. The convex hull area can be a candidate to follow muscle fatigue during FES-elicited contractions and analysis of short length epochs.

Paper Citation

in Harvard Style

N. Nogueira-Neto G., Krueger E., M. Scheeren E., L. S. N. Button V. and Nohama P. (2014). Convex Hull Area in Triaxial Mechanomyography during Functional Electrical Stimulation . In Proceedings of the International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2014) ISBN 978-989-758-011-6, pages 251-256. DOI: 10.5220/0004806702510256

in Bibtex Style

@conference{biosignals14,
author={Guilherme N. Nogueira-Neto and Eddy Krueger and Eduardo M. Scheeren and Vera L. S. N. Button and Percy Nohama},
title={Convex Hull Area in Triaxial Mechanomyography during Functional Electrical Stimulation},
booktitle={Proceedings of the International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2014)},
year={2014},
pages={251-256},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0004806702510256},
isbn={978-989-758-011-6},
}

in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2014)
TI - Convex Hull Area in Triaxial Mechanomyography during Functional Electrical Stimulation
SN - 978-989-758-011-6
AU - N. Nogueira-Neto G.
AU - Krueger E.
AU - M. Scheeren E.
AU - L. S. N. Button V.
AU - Nohama P.
PY - 2014
SP - 251
EP - 256
DO - 10.5220/0004806702510256