The purpose of this work is to assess the maximum energy localization in time-frequency domain of the surface EMG signal of the main lower-limb muscles usually involved in able-bodied walking. The maximum energy localization in time-frequency domain has been identified by means of Continuous Wavelet Transform (CWT), a time-scale analysis method for multiresolution decomposition of continuous-time signals. WT coefficients allowed to reconstruct the scalogram function, providing an estimate of the local time-frequency energy density of a signal. Then, localization of maximum energy density has been identified as the interval in time-frequency where the scalogram is exceeding the 72% of the peak value of energy density in both time and frequency domain. Results showed that the localization of maximum signal energy in time coincided with the region of maximum muscle recruitment during walking. A common frequency band of maximum information content was identified for all muscles between 70 and 160 Hz. These findings could be suitable for both supporting the use of WT for sEMG analysis and providing clinical indications on muscle recruitment during walking.
Time-frequency analysis of surface EMG signals for maximum energy localization during walking / Strazza, Annachiara; Verdini, Federica; Burattini, Laura; Fioretti, Sandro; DI NARDO, Francesco. - ELETTRONICO. - 65:(2017), pp. 494-497. (Intervento presentato al convegno Joint Conference of the European Medical and Biological Engineering Conference, EMBEC 2017 and Nordic-Baltic Conference on Biomedical Engineering and Medical Physics, NBC 2107 tenutosi a fin nel 2017) [10.1007/978-981-10-5122-7_124].
Time-frequency analysis of surface EMG signals for maximum energy localization during walking
STRAZZA, ANNACHIARA;VERDINI, Federica;BURATTINI, LAURA;FIORETTI, Sandro;DI NARDO, Francesco
2017-01-01
Abstract
The purpose of this work is to assess the maximum energy localization in time-frequency domain of the surface EMG signal of the main lower-limb muscles usually involved in able-bodied walking. The maximum energy localization in time-frequency domain has been identified by means of Continuous Wavelet Transform (CWT), a time-scale analysis method for multiresolution decomposition of continuous-time signals. WT coefficients allowed to reconstruct the scalogram function, providing an estimate of the local time-frequency energy density of a signal. Then, localization of maximum energy density has been identified as the interval in time-frequency where the scalogram is exceeding the 72% of the peak value of energy density in both time and frequency domain. Results showed that the localization of maximum signal energy in time coincided with the region of maximum muscle recruitment during walking. A common frequency band of maximum information content was identified for all muscles between 70 and 160 Hz. These findings could be suitable for both supporting the use of WT for sEMG analysis and providing clinical indications on muscle recruitment during walking.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
