Mechanomyographic Analysis with 0.2 S and 1.0 S Time Delay after Onset of Contraction

Resumo: Muscle contractions generate lateral oscillations and motion artifacts that can be detected by MMG sensors placed in the inner and outer sides of the forearm. These artifacts can significantly affect signal processing and eventually it is necessary to eliminate their influence in order to detect movements reliably. One approach is to respect a time delay after the onset of contraction. This study aimed to evaluate the correlation of 0.2 s and 1.0 s time delays after the onset of contraction during wrist movements. This work respected two different time delays before initiating the signal analysis. Two analysis window lengths were evaluated (0.25 s and 0.50 s). The results showed that there are strong correlations between the acquired signals with both time delays, mainly the devised RZ feature (0.81– 0.95). This study was a first approach to determine whether triaxial MMG features can be used for motor prosthesis control. The axial moduli presented strong correlations for all movements and can be productive in future applications. Palavras-chave: accelerometer, prosthesis control, upper limb, time delay, onset of contraction, motion artifact.