filter examples lab view william rose
DESCRIPTION
Filter Examples Lab View William Rose. filter1.vi. filter1.vi. filter1.vi. Zoom in to beginning to see filter edge effects. filter2.vi. Similar to filter1.vi, but uses Zero Phase.vi. Another example of edge effects. Another example of edge effects at each end of a data record. - PowerPoint PPT PresentationTRANSCRIPT
Filter Examples Lab View
William Rose
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
filter1.vi
Department of Kinesiology and Applied Physiology
filter1.vi
Department of Kinesiology and Applied Physiology
filter1.vi
Zoom in to beginning to see filter edge effects.
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
filter2.vi
Similar to filter1.vi, but uses Zero Phase.vi.
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
Another example of edge effects.
Department of Kinesiology and Applied Physiology
Another example of edge effects at each end of a data record.
Department of Kinesiology and Applied Physiology
Fix for Filter Edge Effects Problem
1.Extend the record by adding a segment of time-reversed, inverted-about-the-endpoint data on each end.
2.Filter the extended record.
3.Cut off the extended parts.
4.extend_data.vi does step 1.
Department of Kinesiology and Applied Physiology
extend_data.vi
Department of Kinesiology and Applied Physiology
extend_data_test.vi
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
filter3.vi
filter3.vi calls extend_data.vi to extend the raw data, then filters the extended data, then cuts off the extended parts.
Department of Kinesiology and Applied Physiology
filter3.vi
Department of Kinesiology and Applied Physiology
Department of Kinesiology and Applied Physiology
No more edge problems.
filter3.vi
Department of Kinesiology and Applied Physiology
filter1.m
Department of Kinesiology and Applied Physiology
filter1.m
Department of Kinesiology and Applied Physiology
filter1.mZoomed-in view of start
Department of Kinesiology and Applied Physiology
Phase-less Philtering•Use filtfilt.m in Matlab.
•Labview routine filter2.vi does forward –backward filtering with Zero Phase.vi, but it has edge effects at start and finish.
•We do not give a Matlab analog to filter2.vi, because, by default, Matlab’s forward-backward filter (filtfilt.m) eliminates edge effects.
Department of Kinesiology and Applied Physiology
filter3.mHighlighted lines differ from filter1.m.
Department of Kinesiology and Applied Physiology
filter3.mNo visible edge effects.
Department of Kinesiology and Applied Physiology
filter3.mNo visible edge effects at either end.
Department of Kinesiology and Applied Physiology
filter3.mNo visible edge effects.Data file: force_isometricelbowext_healthyadult_shortseg.txt
Department of Kinesiology and Applied Physiology
filter3.mNo visible edge effects at either end.Data file: force_isometricelbowext_healthyadult_shortseg.txt