Engineers from Duke University have invented an inexpensive printed sensor that can monitor the tread of car tires in real time, warning drivers when the rubber meeting the road has grown dangerously thin. If adopted, the device will increase safety, improve vehicle performance and reduce fuel consumption.
“With all of the technology and sensors that are in today’s cars, it’s kind of crazy to think that there’s almost no data being gathered from the only part of the vehicle that is actually touching the road,” said Aaron Franklin, Associate Professor.
In collaboration with Fetch Automotive Design Group, the researchers demonstrated a design using metallic carbon nanotubes (tiny cylinders of carbon atoms just one-billionth of a meter in diameter) that can track millimetre-scale changes in tread depth with 99 per cent accuracy. In a paper published June 9 in IEEE Sensors Journal, Franklin and his colleagues flesh out their sensor design.
The core of the sensor is formed by placing two small, electrically conductive electrodes very close to each other. By applying an oscillating electrical voltage to one and grounding the other, an electric field forms between the electrodes. While most of this electric field passes directly between the two electrodes, some of the field arcs between them.
When a material is placed on top of the electrodes, it interferes with this so-called “fringing field.”
Original reporting from Ken Kingery, Duke University
