[Vision] Measuring the minimum and maximum radius of a particle

[Brett_Percy]

Hi all,

I'm currently developing an upgraded vision application that includes a particle sizing measurement using the IMAQ Particle Analysis VI.

Currently I'm using the Equivalent Ellipse Major and Minor axes, which works fairly well but appears to overstate the area of the particles compared to the previous implementation of the software for this system.  The original software used a maximum and minium radius measurement using the actual perimiter of the particle rather than an equivalent ellipse.

I'm looking at using Max Feret Diameter and Equivalent Ellipse Minor (Feret) instead, and I was wondering if anyone has any experience with this sort of measurement and can offer some advice?  I'm processing up to 100 particles per frame at around 7-8 fps, so I don't know if writing my own LabVIEW code to perform the measurement will be fast enough.

Cheers

Brett Percy

[ABCPrograms]

Hi Brett,

Have you tried using 'Find particles'?

It can detect circles and ellipses.  Don't have labVIEW with me right now, but can you upload an image?

I can see whether I can figure something out that might help you

[Brett_Percy]

Hi Bjorn,

I can detect the particles fine, the issue is with the particle size measurement.  As you can see from the image, most of the particles are not very round.  The previous version of the software caclulated a maxium and minimum radius of the particle, but there doesn't seem to be an exact equivalent in the LabVIEW vision library

Cheers

Brett