Grab the code from this Github. You need to uncomment the uniqueSet array and index tracker in the code for the first time your compile the firmware. Compile and upload to the Arduino.
Scan all the tags that will be used as voting tokens. The UID for each will be printed to the terminal in a C header format. Copy this to your own uniqueSet.h file.
Purchase a high power electric motor, a speed controller, batteries, heavy duty wire, battery chargers, a DC vacuum pump, a DC-DC converter, and main power relays.