Airport dollies for unit load device (ULD) and cargo pallets are standard sized flatbed trolley or platform, with many wheels, roller bars or ball bearings protruding above the top surface for easy loading and unloading of ULD and cargo pallets respectively.
Since ULD/pallet rest on ball bearings, these dollies are equipped with hinge/locks to secure the position of the ULD/pallet on them during tugging transportation.
Therefore, these dollies are custom designed to complement the ULD/pallet's dimension, hinge/fixture position, weak overall physical strength and transportation need.
The apron is a large area that using direct eyesight to find an item is not easy.
Major airports are starting to attach battery power active RFID tags to dollies to facilitate their fleet management.