View Full Version : implementation of a critically damped filter in matlab

02-04-2010, 12:16 AM
Dear list members,

I was wondering how those of you who are using matlab to process their
emg data implement a critically damped zero-lag digital filter as
described by Robertson and Dowling (2003)? So far, I have been working
with a digital zero-lag lowpass Butterworth filter using the "butter"
and "filtfilt" function in matlab to create the linear envelope of an
emg signal but the signal over- and undershoots. Is there an already
implemented filter function one can use for a critically damped filter
as well (e.g. IIR or FIR) or do you determine the lowpass coefficients

Thank you in advance for you advice.


PhD Student (Biomechanics)

Centre for Sports Medicine and Human Performance

Brunel University, West London

United Kingdom