Computer-controlled vehicular traffic

It is no exaggeration that a kid on roller skates can propel himself crosstown, from the East River to the North River, on any of Manhattan's midtown streets in considerably less time than that required by a motorist. And we all have had the frustrating experience of spending more time in a bus between an airport and center city than in making the actual flight of 500 km or more. About five years ago, Boston, Mass., got a foretaste of what complete vehicular strangulation can be like when the granddaddy of traffic jams immobilized all surface transportation downtown for more than three hours. But the future may not be completely bleak: thanks to the digital computer, sensor inputs-and a lot of software synthesis-traffic intersections can be placed under machine control to break up the traffic bottlenecks that have become one of the major blights of our cities.