After two years of testing in a downtown section of Tokyo, an experimental driver information system known as the Comprehensive Automobile Traffic Control Project (CAC) has been expanded to include a stretch of expressway linking downtown with Narita Airport. The CAC system can transmit information three ways: Data from a magnetic field of transmitters buried under the pavement surface are picked up by an antenna mounted under specially equipped vehicles (330 such cars are currently in use) with dashboard instrumentation which gives drivers a visual indication of their desired route (which has been indicated by entering a 7-digit destination code), with illuminated arrows indicating where to enter and exit expressways, and when to start planning a lane change turn, as well as warning of congesiton ahead and recommending an alternate route (The instrumentation also includes warning lights that draw the driver's attention to pedestrian crossings, changing road width, a stop and go traffic, emergency vehicle priority lanes, road construction and the need to reduce speed, with a buzzer sounding whenever the speed limit is exceeded). Roadside antennas transmitt audio communciations to car radios within the immediate area. There are also roadside visual displays carrying messages that can be transmitted and changed from a central control point. Travel time of CAC- equipped vehicles has been shown to be reduced by as much at 15.5 percent.

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Filing Info

  • Accession Number: 00303275
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jan 30 1980 12:00AM