Ian Sample, science correspondent Monday July 12, 2004 The Guardian
A hi-tech device that can bring speeding cars to a halt at the flick of a switch is set to become the latest weapon in the fight against crime.
Police forces in Britain and the US have ordered tests of the new system that delivers a blast of radio waves powerful enough to knock out vital engine electronics, making the targeted vehicle stall and slowly come to a stop.
David Giri, who left his position as a physics professor at the University of California in Berkeley to set up a company called ProTech, is developing a radio wave vehicle-stopping system for the US marine corps and the Los Angeles police department.
Tomorrow, at the Euroem 2004 science conference in Germany, Dr Giri will describe recent trials of the device. The tests proved that the system could stop vehicles from up to 50 metres away.
The bulk of the device is designed to fit in a car boot and consists of a battery and a bank of capacitors that can store an electrical charge. Flicking a switch on the dashboard sends a burst of electricity into an antenna mounted on the roof of the car. The antenna then produces a narrow beam of intense radio waves that is directed at the vehicle ahead.
When the radio waves hit the targeted car, they induce surges of electricity in its electronics, upsetting the fuel injection and engine firing signals. "It works on most cars built in the past 10 years, because their engines are controlled by computer chips," said Dr Giri. "If we can disrupt the computer, we can stop the car." A prototype is due to be ready by next summer.
The Association of Chief Police Officers confirmed that researchers at the Home Office's police scientific development branch are testing a radio wave vehicle-stopping system. "There's a potential to use this type of device to stop criminals on the road. High speed pursuits are very dangerous, especially in built-up areas," said an association spokesman.