Filtering/processing data in crank angle domain?

[xander.cesari]

Hey everyone,

I was wondering if anyone had tips for filtering data in the crank angle domain. I'm a test engineer for engines so I work with crank angle a lot but the current project I'm looking into this for is an instantaneous crankshaft velocity monitoring program. I'm using a CI-Period DAQmx task to monitor the time between pulses from a crank encoder. I have some various noise issues (not quantization) and I wanted to play around with filters to see if that improves it.

But I'm struggling with implementing filters on data without a consistent sampling rate. I've tried setting the sampling rate to the approximate rate based on the RPM (18-36 kHz typically) but to no avail. Has anyone heard of this being done in LabVIEW or have any pointers?

Thanks,

Xander

[preston_johnson]

The NI Sound and Vibration Measurement Suite has functions to transform time sampled data into angle domain.  There are also several functions to process and filter the data once in the angle domain. 

Hope this helps. 

Preston

[xander.cesari]

Preston,

That sounds like it might be a must-have. I'll run it by my higher ups and see if I can buy it.

-Xander