I actually work in a company that has a similar voting system. We print out a card, and we also burn the content of the vote in a rfid chip, that voters can check themselves. The rfid speeds up the counting, but you can always do the manual count to check up with the system. Neither the machine nor the card contain any information that can identify the person, so we can preserve the anonimity. Perhaps you can check out our site :) http://www.vot-ar.com.ar/en/system-votation/
