Advantages of Autran System over the AHS

The proposed AHS (Automated Highway System) would require use of autos which have special steering and speed control equipment that would be very difficult to add to an existing auto and that would be add considerable expense even when installed as original equipment. Not many people would buy such autos until specially equipped roadways exist on which they might operated. Transportation departments are not likely to approve construction of the roadways when most people would not be able use them. It is not clear how AHS is expected to come into being. By contrast, guideways and auto stations or the Autran system can be immediately usable to carry any auto, van or SUV that is not oversize or overweight, particularly including older gas-guzzling and highy polluting vehicles. The AHS has other disadvantages in comparison to the Autran system:

• A user of the AHS system would rely on other users for proper installation, maintenance and control of the required equipment. By contrast, a user of the Autran system relies only on the system operator who has complete control of the carrier vehicles and who could be expected to do everything possible to make sure that carrier vehicles and other components of the system are properly constructed, controlled and maintained.
• The automobiles used in the AHS are powered from gasoline or diesel fuel or, in the case of EVs, from batteries. By contrast, the Autran system uses utility-supplied electrical energy. It thereby avoids petroleum consumption and pollution. It can also reduce EV range problems and the environmental problems that are associated with use of batteries.
• Tires of the vehicles of the AHS are very noisy, produce high traction losses, consume petroleum when being made and present enviornmental problems in their disposal after use. In addition, they can lead to very serious multi-vehicle accidents either from blow-outs or from loss of steering or braking control when rain or ice is on the dedicated roadways. By contrast, the Autran carrier vehicles are supported and guided through wheels moving on tracks in protected positions within tubular guideways. Noise is minimized. No petroleum is consumed. No disposal problems are presented. No blow-outs can occur. Rain, snow and ice have no effect on control. A high degree of safety is obtained which is further enhanced by a control feature that automatically increases traction forces for braking or acceleration when necessary.
• In radar systems proposed for use in the AHS and all other arrangements that might be used to control the speed and path of movement of a AHS vehicle, substantial risks of malfunction would be presented because transmission of energy through substantial distances would necessarily be required between control components of the vehicle and components associated with the roadway. By contrast, risks of malfunction are minimal in the Autran system in which communication components are along and in protected positions in the guideways to be within very short distances from and closely coupled to components on the vehicles at all times.
• AHS proponents have advocated operation of cars in platoons with very close following distances. A loss of control could happen, especially in bad weather, and could be catastrophic. By contrast, vehicles of the Autran system are designed to operate at a following distance that is a function of speed and that produces at least a certain minimum time interval between vehicles. Each vehicle can respond in a small fraction of a second to even a slight reduction in speed of a vehicle ahead so as to provide a high degree of protection against any collision. Even greater protection can be obtained by increasing the time interval when it is possible to do so without decreasing overall traffic flow. It is also possible to increase the time interval between vehicles and/or decrease the speed of vehicles during adverse weather conditions.

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