The headlines singled out Firestone radials and Ford Explorers, but the real problem is much bigger: Underinflated tires can overheat, fail, and help set up a scenario in which the driver loses control and the vehicle flips over. But what if drivers had a little warning or a little help from an onboard computer? A German electronics manufacturer thinks that a so-called smart tire could spell the difference between life and death.
Researchers at Siemens have come up with a sensor built right into the rubber that reports to an onboard computer. The smart tire contains tiny piezoelectric crystals, ceramic chips that vibrate when an alternating voltage is applied. The speed at which the vibration travels depends on temperature and pressure, so the embedded crystals can reveal precisely how the tires are rolling— whether they are performing normally, turning sharp corners, or slipping on slick roads. Those readings, relayed as radio signals to a central computer, could trigger application of the brakes or ease up on the gas. Similar electronic controls are increasingly common in modern vehicles. The computer could also remind drivers to pump up underinflated tires to help prevent them from overheating.
In 1999, tire-related problems led to 830 deaths in the United States alone, according to data from the National Highway Traffic Safety Administration. The total toll from overaggressive driving is much higher. "If you can avoid just 20 percent of these accidents, that would be a very great bonus for everyone," says physicist Hartmut Runge of Siemens. Properly inflated tires also handle more safely, deliver better gas mileage, and last longer. That could mean fewer radials clogging the landfills. Smart tires are currently undergoing tests at the Technical University of Darmstadt in Germany and could appear on production cars in as little as a year.