Plessey Co Plc has developed a radar-operated device designed to be used as a car speedometer, or as part of an alarm system warning drivers that they are too close to objects ahead. When used as a speedometer, Plessey’s speed sensor is attached to the underside of a car and emits two beams; the device then measures the speed between the beams and displays the car’s speed to the driver. Plessey claims the device, which operates at 24GHz, gives figures that are accurate to within 1% of actual speed, whereas conventional systems can be as much as 10% inaccurate. Data from the speed sensor will be used to enhance anti-lock brakes, suspension and other features; Plessey adds that the device is impervious to the elements, can be fitted to any vehicle, and is cheaper than conventional mechanical speedometers. Though Plessey says it can deliver the device immediately, car manufacturers are likely to wait two years before incorporating it into new vehicles. A second application for the systems warns drivers that they are dangerously close to vehicles ahead; adoption of such a system is likely to be delayed further, however, as car manufacturers decide whether such systems should merely inform drivers of possible danger, or automatically reduce the car’s speed. Car manufacturers, demanding just in time delivery, will look for joint venture deals for the device’s production: Volkswagen is among the first to express interest. The technology was derived from a number of military devices. – Andy Evagora