Milling is performed by construction equipment called milling machines or cold planers.^[10] These machines use a large rotating drum to remove and grind the road surface. The drum consists of scrolls of tool holders.^[2] The scrolls are positioned around the drum such that the ground pavement is moved toward the center and can be loaded onto the machine’s conveyor belt.^[2] The tool holders can wear out over time and can be broken if highway structures like manholes are encountered while milling.^[2]