Radio/computer bus control system
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• A system which will provide the traffic controller of a bus undertaking with a continuously up-dated picture of the location of each bus in the operational fleet is being developed by Marconi Co. Ltd., Chelmsford, and a practical demonstration was given at the head office of the Bristol Omnibus Co. Ltd. on Wednesday.
The Marconi Myriad on-line digital computer is installed in the bus fleet control room, which is kept in automatic radio contact with each bus in the fleet and continuously monitors its progress along its route. Computer output is fed to visual display units which can be selected at will by the controller to show various aspects of the overall situation, such as the position of individual buses in a selected area; this enables remedial action to be taken if necessary.
Communication between the control room and the bus is by a VHF radio link which provides both automatic recovery of data regarding its position and for two-way communication between driver and controller by radio-telephone. Using the latter, instructions can be relayed to the driver. An alarm system is also incorporated which, when actuated on a bus, indicates an emergency together with the position of the bus.
The Marconi system provides the bus position data by means of an optical scanner on the vehicle picking up coded responses from static "beacons" placed at fixed locations along the routes. The beacons consist of strips of reflective material arranged in such a form as to give a positive indication of their location in coded form—they are fitted to lamp posts or the sides of buildings along the route.
A distribution of 10 beacons per mile is suggested as being an acceptable level. The information from the beacons could equally
well be used by police, ambulance, fire brigade or other service vehicles fitted with the visual scanner and using different radio frequencies.
The Marconi X2000 display is claimed to be highly versatile and will possess a selection switch enabling the display of the entire bus system or a single route or number of routes. An alternative display mode permits a "window" or rectangular box to be steered over the whole area by a manual control and for a magnified picture of the enclosed area to be displayed on pressing a button. A positive identification code for each bus on the display is shown against its position.
Advantages of the system are the simplification of staff supervision, the correction of irregularities and a substantially reduced need for inspectors and regulators. Greatly improved vehicle utilization should also be possible.