HAS-Motion Software Documentation

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surface emg signals typically have a frequency content between 50 and 500 hz. these signals may have a dc bias. it is common to apply a high pass filter with a cutoff frequency of 50 hz to emg signals prior to any other processing to remove the dc bias.

note: many laboratories assume a frequency content between 20 and 500 hz

note: applying a high pass filter will effectively remove any dc bias in the signal.

! by default, visual3d uses a second order butterworth bidirectional filter (resulting in a
! fourth order filter) for lowpass/highpass filtering.

! high pass filter
highpass_filter 
/signal_types= analog 
/signal_names= emg1+emg2+emg3 
/signal_folder= original 
! /result_suffix= 
! /result_folder=processed 
! /filter_class=butterworth 
/frequency_cutoff= 50 
/num_reflected= 0 
/total_buffer_size=100 
/num_bidirectional_passes=1 
;