Keeping robots on the right route

, a manufacturer of automatic guided vehicles (AGV) and the

(NIST) are developing advanced sensor processing and modelling algorithms. They hope their research will help robot forklifts verify the location and orientation of pallets laden with goods.

The experimental system utilises two onboard, single scan-line LADAR devices to negotiate obstacles and hone in on warehouse pallets. LADAR (Laser Detection and Ranging) is an optical technology which measures properties of scattered laser light to find range and other information about a distant target. One LADAR device, located at the base of the AGV, is used as a safety sensor to detect obstacles such as humans in the forklift's path. It can also be used to scan inside a truck's cargo area to detect the presence of a pallet or define distances from the forklift to the truck's inside walls.

The other sensor, called the Panner, is a panning laser ranger mounted on a rotating motor at the top front of the AGV. The Panner acquires many scan lines of range data that allows the scene in front of the device to be reconstructed in various visual formats such as a pseudo-coloured coded image (where colours indicate relative proximity to an object) or a 3-dimensional data point "cloud."

A computer model is then derived from the data with the output sent immediately to the AGV's control centre. This allows the robot forklift to manoeuvre, load and unload pallets, verify the remaining space within the truck being loaded, and track the number of pallets still needing handling.