2D Technique for a 3D Problem

If you read as many machine vision product brochures as I do you’ll have seen more than a few screenshots of edge tools checking electronic components for bent pins. Unfortunately, the problem with this is that pins bend in three dimensions, so they can appear “good” in a 2D image while still being “bad.” So how do you check for bend, and better still, is there a way to measure the degree of bend?

A team of researchers in Japan have come up with a solution that I really like. As discussed in “Detecting and measuring bent pins on electronic components,” (spie.org, October 7th 2009,) their solution is to move a light source around the pins and look at how it reflects off the shiny metal surface. Implementation could be a little tricky because there’s some motion required (unless you individually illuminated a line of LED’s,) but that aside, this seems like a rather elegant solution to what can be a challenging problem.

As bent metal is pretty common in manufacturing industry, I suspect the technique has quite broad application. I’d be interested in hearing any ideas. Anyone?