Cars drive themselves at automated highway demo
Demo `97, sponsored by the National Automated Highway System Consortium (NAHSC) in August in San Diego, CA, gave a whole new meaning to the Greyhound Bus line slogan "Leave the driving to us." Indeed, at the public unveiling of the 7.5-mile automated highway test track, demonstrations of intelligent transportation systems included not only a self-driving bus (Houston METRO; Houston, TX), but a smart tractor-trailer (Eaton Vorad; Cleveland, OH).
Demo `97 was a major milestone in the Automated Highway System (AHS) project, and the staging area was the scene of furious activity. Seven different automation scenarios were played out during the course of the demonstration, ranging from a platoon of self- driving cars that tracked magnetic nails in the roadway to a bus that relied on machine vision to warn of lane departures. One scenario not for the faint-hearted involved an automatically piloted semi-truck bearing down on a stationary Corvette at approximately 65 mph. Radar systems and machine-vision units on the truck registered the presence of the fiberglass vehicle and brought the truck safely to a stop behind it.
Many vehicles incorporated machine vision, liquid-crystal displays, and laser radar systems. In the scenario headed by researchers at the University of Ohio (Dayton, OH), for example, CCD cameras monitored the lane position of the test car. A front-mounted laser radar system (Honda; Tochigi, Japan) integrated with the car`s intelligent cruise control system monitored the size, velocity, and position of a leading vehicle and used the data to maintain following distance by automatically applying brakes. The test car also checked its blind spot and automatically changed lanes to pass a slow vehicle, then moved back into the travel lane. The scenario ended when the test car detected a stationary vehicle a head and came safely to a stop.
Prototype system targeted for 2002
Next up on the AHS agenda is the demonstration of the complete prototype automated highway system in 2002. Gradually, the technology will be integrated into the nation`s highways (see Laser Focus World, June 1996, p. 108). One important transportation requirement has not been provided for in this grand scheme, however--at present, none of the vehicle sensors have been fitted with pattern recognition to permit them to identify hitchhikers. On the automated highways of the future, it would appear that the free ride will be a thing of the past.o
Smart cars are fitted with redundant sensor systems (machine vision, conventional radar, laser radar) to detect obstacles and maintain lane positions. Computers control the steering, acceleration, and braking systems through actuators, and liquid-crystal displays provide the driver interface.