my knowledge on what you have mentioned is very little i understand why an LVDT wont work. I am starting to think that it would be easier building a sorting system (Like a coin cointer) with sensors counting the components as they fall through. But then i will have to deal with semiconductors getting 'knotted' and clogging up the funnel.

////erik thanks for the clue, found suppliers of transducers i am waiting for a pricelist.

enjoy