A demonstration on the cooperative driving with 5 automated vehicles was conducted in November 2000 as "Demo 2000 Cooperative Driving" to show the feasibility and potential of the technologies. In this paper the technological overview on the demonstration is described. The cooperative driving, aiming at the increase in the safety and throughput of road traffic, here means that automated vehicles drive in a flexible platoon with a short inter-vehicle distance over a couple of lanes. The vehicles for the demonstration are equipped with the RTK-GPS for the vehicle localization, a laser radar for the detection of an obstacle or a preceding vehicle, the inter-vehicle communication unit, and the onboard display for passenger to locate the neighboring vehicles. The localization data acquired at every 200 msec are employed for the lateral and longitudinal control of the automated vehicles with the precise map of the demonstration site. The data on the location and speed of each vehicle in the platoon and the location of an obstacle are transmitted at every 100 msec over the inter-vehicle communications. The protocol, nicknamed as DOLPHIN (Dedicated Omni-purpose inter-vehicle communication Linkage Protocol for Highway automatioN) after the ecology of the dolphins, is designed for the dedicated use in the demonstration, and is based on the CSMA with the 5.8 GHz Dedicated Short Range Communication (DSRC). The 5 automated vehicles drove at 40 - 60 km/h on a test track according to the demonstration scenario including stop and go, platooning, lane changing, passing, merging, and obstacle detection and avoidance.
Abstract