The plan is to use an old steel box and add a fingerprint scanner hooked up to a pro micro (uno for prototype). The problem is that I want to enter an exact amount such as 4710 and have it output the exact notes like in this case 1000(x4) 500(x1) 100(x2) and (10x1) notes. The programming is easy but I can't figure out the mechanical layout. I've thought of using a pile of mixed notes with a color sensor (as all our notes are uniquely colored) at the top which makes the servo roll back the notes that aren't needed and rolls out the notes as they match those needed and after the money is out another servo can add back to the pile the discarded notes. The problem with this method is that it will require the pile on exact heights for the motor to properly pull/push therm. what should I do?
Also as for the depositing of money, rotating the motor backwards is a very simple solution but what can I do to sense the presence of a new note?