Environment: Trafficking by Computer

• Share

The computer, which is supposed to solve all problems, has now been handed the problem of traffic control in downtown Washington, D.C.

The experiment, covering half a square mile near the White House, was devised by the Sperry Rand Corp. under a $4.1 million contract with the Federal Highway Administration. Electronic sensors, embedded in the streets, monitor the flow of vehicles above them. Telephone wires carry the information to a central computer that is programmed to analyze these data immediately, and to send back the appropriate commands to street lights.

Similar but less sophisticated systems are at work in a number of cities from Berlin to New York to Tokyo, but the Washington program has special features. Some 450 Washington buses are now being equipped with radio transmitters that will link them to the central computer. Thus, if the driver wants to set up a series of green lights for himself, he can press a button requesting the computer to give him those signals at cross streets. If the computer, upon scanning the traffic in the area, decides that the request is justified, it will send commands to the appropriate street lights. If the computer thinks otherwise, it will ignore the request.

Just to make sure all systems are go, the computer also shows the traffic flow on a war-room-type display board at the control center. There, traffic engineers can take personal command of the lights if the computer shows signs of faltering. So far, it hasn't. Already, 117 intersections have been wired into the network, and by November it will be fully operational.