Army scientists have developed a high spatial resolution, high-sensitivity pressure sensing system for dangerous and difficult-to-access locations. The patented technology is available via license agreement to companies that would make, use, or sell it commercially.
Material science and civil engineering applications require measurements of localized pressure loading to a high degree of spatial resolution. Localized material responses are associated with high pressure from shocks, explosives, gas-gun, and laser-driven events. Unfortunately, traditional pressure sensors, such as bonded resistance strain gauges are impractical for taking measurements at locations that are difficult to access, for example, exterior surfaces of skyscrapers or undersides of bridges. These sensors require extensive wiring and instrumentation, increasing overall system size, making deployment complicated and slow. In addition, the scale of traditional pressure sensors reduces possible pressure mapping resolution.
More sophisticated sensors rely on the measurement of a wavelength shift in carbon nanotubes or measurement of quantum dot fluorescence. However, they’re commonly only sensitive to pressures on the order of gigapascals (GPa) and are inadequate for measuring pressures on the order of megapascals (MPa) or lower.
There is a need for a readily deployable sensor for dangerous or inaccessible locations, which can be used to probe a localized material response to pressure both at high spatial resolution and high sensitivity.
A team of Army scientists has developed a solution to this challenge in the form of a pressure sensing system, comprising a visible light laser source with 5mW power, and a nanocomposite pressure sensor with quantum dots embedded in the sensor matrix. Under pressure, the quantum dots in the sensor matrix fluoresce when illuminated by the laser. A spectrometer detects the fluorescent signals and transforms them into a digital format. The data processor then calculates the actual fluorescence intensity ratio and compares it against intensity ratios and pressure values in a coupled database. The system outputs the pressure value correlated with the detected fluorescence intensity ratio.
- The system is sensitive to compression loading in the range of approximately 0.5 MPa to 110 MPa
- The pressure sensor itself can be a solid device or a coating on an object or structure, with the sensor matrix being made of epoxy or another polymer with a transmittance of approximately 95% to 100% for the visible light spectrum
- The quantum dots can range from approximately 1nm – 10 nm in diameter and be CdSe/ZnS core-shell quantum dots or made of core-shell semiconducting nanocrystals
- Businesses can commercialize the technology by licensing U.S. Patent 10,330,541 from the Army
- License fees paid to the Army are negotiable
- Businesses that license the technology may have the opportunity to pursue collaborative research with the inventors
- Testing data may be available to companies evaluating the technology
- TechLink guides businesses through evaluation and licensing; services provided at no cost