Duke University researchers invented an inexpensive printed sensor that can monitor the tread of car tires in real time. The sensor warning drivers when the rubber meeting the road has grown dangerously thin.
The device will increase safety, improve vehicle performance and reduce fuel consumption.
Researchers have demonstrated a design using metallic carbon nanotubes that can track millimeter-scale changes in tread depth with 99 percent accuracy.
The technology relies on the well-understood mechanics of how electric fields interact with metallic conductors. 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.
However, measuring the interference through the electrical response of the grounded electrode, it is possible to determine the thickness of the material covering the sensor.
The sensor made from a variety of materials and methods. The researchers optimized performance by exploring different variables from sensor size and structure to substrate and ink materials.
Printing electrodes made of metallic carbon nanotubes on a flexible polyimide film. Besides providing the results, the metallic carbon nanotubes are durable enough to survive the harsh environment inside a tire.
The sensors printed on most anything using an aerosol jet printer, even on the inside of the tires. Well, it is not certain that direct printing will be the best manufacturing approach, whatever approach is ultimately used.
Researchers also want to explore other automotive applications for the printed sensors, such as keeping tabs on the thickness of brake pads or the air pressure within the tires. This is consistent with a key trend in the automotive sector toward using embedded nanosensors.
More information: [IEEE]