One of the most common ways that car owners will know that they should change tires is through the ‘penny’ method. It involves inserting a Lincoln-head penny into the tread and check whether Lincoln’s entire head remains visible. If it does, then the owners should already take it a sign that the tire is old.
Researchers at Duke University in Durham, North Carolina in the United States have found a smarter, easier, cheaper (yup) and more accurate way to do this.
Electrical engineers there developed an inexpensive sensor which monitors the tread of car tires. In real time.
Designed together with Fetch Automotive Design Group, the sensor uses metallic carbon nanotubes that can track millimeter-scale changes in tread depth, and with an accuracy of 99%. The system is all about the mechanics of how electric fields interact with metallic conductors.
Two very close electrically conductive electrodes are applied with an oscillating electrical voltage to one and grounding to another. This forms an electric field, some of which arcs between them.
Photo by Duke University
But when a material is placed on top of the electrode, it interferes with what is called the “fringing field.” This interference is measured through the electrical response of the grounded electrode, allowing to determine the thickness of the material covering the sensor. That’s how the sensor detects that the tires have gone too thin.
Photo by Duke University
The researchers say that the sensors can be printed on any surface using an aerosol jet printer. Franklin noted that sensors should cost far less than a penny apiece once they’re being made in quantity.
“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 of electrical and computer engineering at Duke.
He referred to the tire tread sensor they developed as the “perfect marriage between high-end technology and a simple solution.”
Furthermore, Franklin said that the technology is not at all limited to cars.
“This setup could be used with just about anything that isn’t metallic or too thick,” he said. “Right now we’re focusing on tires, but really anything you’d rather not have to cut apart to determine its thickness could be monitored by this technology in real time.”
Source: Phys.org
