Improve Traffic: Let Your Car Drive

A new study concludes that many traffic jams could be prevented if onein five vehicles on the road used new adaptive cruise-control.

1 minute read

August 1, 2004, 7:00 AM PDT

By Chris Steins @planetizen


"Synchronized flow is, in physics-speak, in unstable equilibrium: The slightest change, such as a driver changing lanes and forcing others to brake, tips the system into a new state. The result is stop-and-go traffic, a true jam.Physicists are exploring whether adaptive cruise control can prevent this. In ACC, a radar sensor gauges the distance between cars, automatically adjusting speed to maintain a safe distance. Because ACC, which has become standard on some luxury vehicles, can adapt instantly if the lead car brakes (humans take about 0.75 second to react), cars can tailgate safely. ACC can therefore pack more cars into a mile of highway, increasing a road's de facto capacity."

[Editor's note: The link below is available to non-subscribers for a period of 6 days.]

Thanks to Chris Steins

Saturday, July 31, 2004 in Wall St. Journal

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