COMMUNICATION SYSTEMS FOR TODAY'S AND TOMORROW'S MOTORISTS

COMMUNICATION SYSTEMS DEVELOPED BY GENERAL MOTORS RESEARCH LABORATORIES TO AID THE MOTORIST IN DRIVING TASKS ARE COVERED. A REVIEW OF THE RESEARCH LABORATORIES' PROGRAMS INCLUDES ROADSIDE LOW FREQUENCY SIGNALLING, VISUAL SIGNING, DRIVER AID INFORMATION AND ROUTING, AND RECENT WORK FOR THE FEDERAL HIGHWAY ADMINISTRATION, BUREAU OF PUBLIC ROADS INVOLVING AN ELECTRONIC ROUTE GUIDANCE SYSTEM, IN ADDITION, A NATIONWIDE COMMUNITY PROGRAM FOR COORDINATING CITIZENS TWO-WAY RADIO FACILITIES IN LOCAL EMERGENCIES ALONG WITH THE CITY OF DETROIT DRIVER AID NETWORK IS DESCRIBED. ONE OF THE EARLIEST ELECTRONIC DRIVER AIDS WAS THE ROADSIDE LOW FREQUENCY SIGNALLING SYSTEM. THIS EXPERIMENTAL SYSTEM WAS LATER PRODUCED BY THE DELCO RADIO DIVISION UNDER THE NAME HY-COM. TODAY THIS SYSTEM IS CALLED AUDIO SIGNING. THE TRANSMITTER OUTPUT FED A WIRE LOOP ADJACENT TO THE ROADWAY. THE LENGTH OF THE LOOP WAS ADJUSTED SO THAT A MOTORIST TRAVELLING AT THE SPEED LIMIT WOULD RECEIVE TWO COMPLETE MESSAGES. THE MESSAGES WERE EITHER RECORDED ON A CONTINUOUS TAPE LOOP OR COULD BE CONTROLLED FROM A MASTER STATION. MESSAGES WOULD BE HEARD THROUGH THE CAR RADIO SPEAKER ONLY WHEN PASSING A HY-COM TRANSMITTER, WHILE THE ENTERTAINMENT AUDIO WAS AUTOMATICALLY MUTED. THIS WAS ACCOMPLISHED BY PLACING A TRIGGER LOOP AHEAD OF THE MESSAGE LOOP TO SIGNAL THE PRESENCE OF A HY-COM TRANSMITTER. THE HY-COM SYSTEM WAS TESTED AND THE RESULTS DOCUMENTED IN A 1967 REPORT BY THE GEORGIA INSTITUTE OF TECHNOLOGY. INTERESTINGLY, A SYSTEM SUCH AS DESCRIBED IS NOW BEING INSTALLED ON ROUTE M-4 IN ENGLAND. THE SYSTEM WILL OPERATE AT 100 KHZ WITH LOOPS 3/4 MILE LONG TO PROVIDE TWO COMPLETE MESSAGES AT 70 MPH. TWO CHANNELS WILL BE EMPLOYED, ONE FOR DIRECTIONS AND THE OTHER FOR EMERGENCY MESSAGES. THE USE OF TWO CHANNELS WAS FIRST PROPOSED IN 1959. THE POSSIBILITY OF IN-CAR DISPLAY OF ROAD SIGNS SUCH AS SPEED LIMITS, CURVES, STOP, RAILROAD, ETC., LED TO THE DEVELOPMENT OF VISUAL SIGNING. A GENERAL MOTOR'S SYSTEM EMPLOYED CYLINDRICAL MAGNETS BURIED IN THE ROADWAY TO ESTABLISH A CODED SEQUENCE OF NORTH-SOUTH MAGNETIC FIELDS CORRESPONDING TO THE CODE ASSIGNED TO THE MESSAGE ON THE ADJACENT ROADSIDE SIGN. TECHNIQUES OTHER THAN THE MAGNETS CAN BE EMPLOYED TO GENERATE THE DISPLAYED SYMBOLS BUT THE MAGNETS OFFER A MAINTENANCE-FREE SCHEME WHICH SHOULD BE ATTRACTIVE TO HIGHWAY AUTHORITIES. /HSRI/

• Supplemental Notes:
  • 9 Pp, Figs, PHOTS, REES
• Corporate Authors:

  General Motors Corporation

  Research and Development Center, 30500 Mound Road
  Warren, MI  United States  48090
• Authors:
  • Weller, E F
• Publication Date: 1970-3

Subject/Index Terms

• TRT Terms: Communication; Communication systems; Drivers; Electronic equipment; Highway traffic control; Information display systems; Information management; Information, data, and knowledge; Loops (Control systems); Low frequency; Magnets; Motorist aid systems; Radio; Roadside; Routing; Signs; Visual aids
• Uncontrolled Terms: Guidance
• Old TRIS Terms: Displays; Electronics (Traffic); Highway user services; Loops (Electrical); Two way communication
• Subject Areas: Data and Information Technology; Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00225937
• Record Type: Publication
• Source Agency: Highway Safety Research Institute
• Files: TRIS
• Created Date: Apr 25 1971 12:00AM