October 2003

Prototype

Continued from page 4

By Technology Review

Out of Gas?

Your car's fuel gauge is on "e." should you stop for gas, or can you eke out a few more kilometers? You can't know for sure, because the mechanical floats used in most automobile gas tanks are imprecise. But a cheaper, more durable type of fuel gauge, based on technology used in flat electronic keypads, could tell you exactly, with digital accuracy, how much fuel is in your tank. The pads, based on technology from Wheaton, IL-based TouchSensor Technologies, consist of electrodes mounted behind a plastic plate that create an electric field above the plate. Liquid sloshing over the plate interrupts this field, tripping a switch. Material Sciences, in Elk Grove Village, IL, has licensed the core technology and plans to further develop and market the pads to Detroit automakers, which could embed vertical columns of the devices into the walls of gas, oil, coolant, or windshield wiper fluid tanks; the pads would sense falling fluid levels and transmit precise data to a dashboard display. And because the devices could be placed directly in the walls of plastic tanks as the tanks are molded, they should be cheaper than mechanical-float systems as well.