A bar scan reader mounted each side of the trailer doors and each pallet with a large bar code or QR reader that auto scans each pallet on and off. 
Seems logical to me but I stand to be corrected as I have not done this type of work.
A bar scan reader mounted each side of the trailer doors and each pallet with a large bar code or QR reader that auto scans each pallet on and off.
Seems logical to me but I stand to be corrected as I have not done this type of work.