Analysis of Digital Filtering Design Based on Surface EMG Signals

The Butterworth IIR digital filter is designed to replace the high-cost analog filter to obtain a desirable surface EMG signal by addressing both the noise of the original surface EMG signal (SEMG) in the industrial frequency interference and baseline drift. The digital filtering design includes a 50 Hz I.F. trap and high-and low-pass digital filters. Experimental results show that the filtering process achieves -60 dB trap attenuation at 50 Hz and effectively filters out both high-and low-frequency signals, which supports the subsequent miniaturization of EMG bio-devices.