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Our Sensor Related ResearchGenerously funded by NASA, NIH, and NSF. We are developing several new remote query sensor platforms for environmental sensing. The exciting aspect about our technology is that sensor information can be obtained remotely, without any direct physical connections such as wires, nor any specific alignment requirements as needed for laser telemetry. Magnetoelastic Sensors
Magnetoelastic thin-film sensor Magnetoelastic thin-film sensors can be considered the magnetic analog of an acoustic bell: in response to an externally applied magnetic field impulse the sensors ring like a bell, emitting both magnetic flux and acoustic energy with a characteristic resonant frequency. The magnetic flux can be detected remotely, external to the test area, using a pick-up coil, or the acoustic energy by a microphone. By monitoring changes in the characteristic resonant frequency of the sensor multiple environmental parameters can be measured including temperature, pressure, velocity of ambient medium and, when immersed in a liquid, viscosity, liquid density, and surface tension. In combination with mass changing, chemically responsive layers, such as polymers or ceramics, remote query chemical sensors can be made.
Remote query mechanism for magnetoelastic sensors The remote query capability as illustrated above allows the magnetoelastic sensors to be monitored from inside sealed, opaque containers such as food packages or people. Depending upon the application magnetoelastic sensors can be sized from micrometer to millimeter dimensional scales, and have a material cost of approximately $0.001 allowing for their use on a disposable basis. Printed-Circuit Resonant SensorsThese sensors are comprised of an inductor-capacitor (LC) printed circuit pair, in planar form, the resonant frequency of which changes in response to different environmental parameters including pressure and, when made in conjunction with a humidity-responsive thin film, humidity levels. The resonant frequency of the sensor is detected using a remotely located loop antenna. Within the interrogation zone the sensor perturbs the impedance spectra of the loop antenna, from which the resonant frequency of the sensor is determined. Phytoplankton-Based Chemical SensorsWe have used the printed-circuit resonant circuits to monitor changes in the electrical properties of phytoplankton laden solutions in response to different atmospheric concentrations of CO and CO2. In this fashion instead of designing expensive chemically responsive materials, such as polymers, we use very inexpensive ($20/gallon) splashes of phytoplankton in combination with smart signal processing as our chemical sensors. If you are interested in our sensor work, please download some of our sensor related publications.
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