CACS - Urban traffic control system featuring computer control

In Japan, the number of automobiles has exceeded thirty million and the number of driver's license holders reached thirty-five million (approximately thirty-five percent of the total population) at the end of 1976. Automobile traffic in many cities has been increasing rapidly year by year. Automobiles and trucks, at present in Japan, perform the most important part of a means for transporting passengers and goods. In fact, for seven years, the amount of transportation by automobiles exceeded that by railways in Japan. Increased use of automobiles in cities, on the other hand, has caused many serious problems: traffic congestion, traffic accidents, air pollution from exhaust gas etc. For example, more than thirty persons are killed by automobile accidents every day. These problems impose great losses and strains on city dwellers. The city traffic problem has become one of the most important social problems in Japan. To solve this traffic problem, many means and systems have been considered and applied to the cities. Area traffic signal control systems have been installed in the major cities of Japan. Many big cities have also been equipped with air pollution surveillance systems. Enforcing traffic regulations, extending safety facilities, developing new city transportation systems and many other means have been tried. It cannot be said, how~ver, that the situation has changed for the better. Both time involved and area covered by traffic congestion in the city are still increasing. As a result even with an increase in the number of vehicles, the transporting capacity of automobiles in the city is decreasing. In order to solve the city traffic problem, it is basically necessary, in addition to the above, to consider a means for increasing efficient utility of the road network in a city. For this purpose, Comprehensive Automobile Control System (CACS) project, which is introduced in this paper, was established and is continuing. The purpose of the CACS project is to develop an effective means and system for controlling the city automobile traffic comprehensively and efficiently. Technically, this project aims to develop a total information processing system for the automobile traffic by combining car electronic device, car-ground communication, computer control ~nd network technologies. This sys-