Container Chassis Alignment and Measurement Based on Vision for Loading and Unloading Containers Automatically

A vision-based chassis alignment and measurement system (CAMS) is proposed in this paper, which can be applied to loading (unloading) containers to (from) the chassis of external trucks automatically at yard stack area working in side-feeding manner. A vision system is designed to guide and align a chassis to a preset transfer area on floor of yard, which can be also used for measuring the position of the chassis. The vision system consists of seven cameras carefully calibrated and it is implemented on floor of yard to be able to work independently of an automated transfer crane. The CAMS can deal with a chassis with a 40/20 feet container as well as an empty chassis. Through experiments in a 14:1 scaled environment, we found that the CAMS could guide and align a chassis in real time and measure the position of the chassis within a permissible error.