Has anyone connected a laser for distance measurement and done filtering in LabVIEW? - looking for sample code

[Jay Grassel]

With a laser running over a rough surface there is usually unwanted noise to be filtered - are there any specific examples of how to do this the best way - for LabVIEW?

[Ben]

Hi Jay,

Selecting the proper type of filter and configuring it can be tricky. There is a tutorial somewhere on the NI site that gives you a flow chart to help select the proper type.

Now once you have selcted the proper type, using it in the real world leads to another complication, i.e. Phase Shift.

The filtered signal ends up being phase shifted due to the filtering. The magnitude of this phase shift will generally be of the same order as the filter. NI has a nice example at

http://zone.ni.com/devzone/explprog.nsf/6c163603265406328625682a006ed37d/cf7004be04f4e15786256a2d0050b997?OpenDocument

(if this link does not work, search on "zero phase") That demonstrates a filter with zero phase shift.

I hope this helps,

Ben

P.S. I owe you $0.50