UW-Madison researchers have created a technology for sensing vibrations at “much lower cost” than traditional systems, with possible applications in health monitoring, predicting natural disasters and structural testing.
WARF included the technology in its latest roundup of top licensing prospects among its portfolio of engineering and computer science university research.
Its inventors note the importance of real-time vibration sensing, as it can help predict earthquakes, typhoons and avalanches, along with other uses in geological surveys. And while vibrations from human breathing and heartbeats are key signals for health monitoring, the ability to monitor vibrations in structures can also be used to test industrial equipment, vehicles and buildings.
Existing approaches usually involve an electronic sensor attached directly to the vibrating surface to gather accurate measurements of frequency and motion. But the inventors say these current options can involve “prohibitively high” costs, especially if it’s necessary to monitor multiple locations at the same time.
“In many sensor applications providing electrical power to the sensor location or by batteries can be impractical,” they wrote in the patent. “For this reason, there is substantial interest in non-contact vibration sensing, that can monitor multiple locations or that avoids the need for a local source of power.”
To address this demand, the scientists created a “passive vibration sender” to boost the amplitude of target vibrations, giving remote sensing systems the ability to detect it in a nuanced way.
Non-contact vibration sensing systems can involve video imaging of a vibrating surface, or measuring changes in radio waves reflected from the surface, according to the patent.
But inventors say low sensitivity is a major limitation to non-contact approaches, as camera systems used for this purpose need “extremely high” resolution to gain meaningful information, while radio signals’ long wavelength result in “nearly undetectable” changes for measurement.
Their solution offers a way to amplify vibration signals to make these approaches more viable. The design outlined in the patent “potentially provides a much lower cost” than active electronic sensors, doesn’t require a power source and reduces vibration at other frequencies, improving the signal.
The patent includes diagrams of the technology’s structure, as well as potential ways to mount it on the body, either with a wearable strap or article of clothing.
The inventors listed on the patent include Profs. Chu Ma and Bhuvana Krishnaswamy of the UW-Madison College of Engineering as well as Dajun Zhang and Muhammad Osama Shahid.
See the overview from the Wisconsin Alumni Research Foundation.
