A statistical method for electromyographic envelope
determination
Ana Paula Rodrigues Ramos
Universidade Federal de Uberlândia
[email protected]
Lílian Ribeiro Mendes Paiva
Universidade Federal de Uberlândia
[email protected]
Luciano Vieira Lima
Universidade Federal de Uberlândia
[email protected]
Alcimar Barbosa Soares
Universidade Federal de Uberlândia
[email protected]
ABSTRACT
The information extracted from
electromyographic signals can provide
researchers with a number of useful
information to study muscle activity. Various
techniques can be found in the literature to
perform such analyses. However, most of
them,
when
dealing
with
dynamic
contractions, for instance, do not take
adequate care when highlighting the correct
window of the collected signal. Hence, the
results may refer not only to the muscle
contraction but also to other parts of the
collected signal that may contain inactivity or
artifact noise.
This work presents a method to
automatically detect the EMG envelope. In so
doing it is possible to find out the correct time
when the contraction begins and ends. The
proposed technique is based on statistical
analyses of the raw signal. To locate the
boundaries of the EMG envelope, the
computational algorithm searches for points
where the signal reaches, at least, three
standard deviations with regard to the average
of the whole data.
The results have shown that the
method can correctly detect EMG envelopes
even on very noise conditions.
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