Not long ago the biggest contribution modern electronics had made to safe driving was the synthesized voice that announced, "Your door is ajar." But with innovations such as computer-coordinated fleet routing and digital navigation harnessed to wheel sensors, vehicles have become much smarter.

The latest advance is vehicular on-board radar (VORAD), an electronic system that warns drivers of impending collisions and promises to save lives and sheet metal. And insurance expenditures as well? "Ultimately, we hope the technology will drive the cost of insurance down by reducing or even eliminating rear-end accidents," says Rich Rosenthal, assistant vice-president of strategic planning at All State Insurance in Northbrook, Ill.

Indeed, with All State capital behind it to hasten development, one company, IVHS (Intelligent Vehicle Highway System) Technologies, of San Diego, has already begun installing VORAD in trucks, following extensive field testing. A VORAD collision-warning unit works essentially like a police speed gun. It emits a low-output microwave signal that bounces off another vehicle -- so you don't.

Technical roadblocks to electronic collision avoidance have been daunting. In a split second, a sensor must be able to recognize the difference between a harmless object and the rear of a rapidly slowing car in a fog patch. In VORAD's case, that distinction is determined by complex algorithms that analyze the shape of the return signal. Expected soon: automatic application of the brakes and throttle control.

A VORAD unit costs about $1,000 per truck. Contact IVHS at 619-674-1200. -- Robert A. Mamis

* * *