A wireless magnetoelastic micro-sensor array for simultaneous measurement of temperature and pressure

Magnetoelastic thick film sensors mechanically deform when subjected to a m agnetic field impulse, launching elastic waves within the sensor the magnit ude of which is greatest at the mechanical resonant frequency. As the senso rs are magnetostrictive, the mechanical deformations launch magnetic flux t hat can be detected remotely. The characteristic resonant frequency of a ma gnetoelastic sensor, which is a function of the length, density, elasticity and Poisson's ratio of the sensor material, changes in response to tempera ture, pressure, ambient flow rate and, in combination with a mass changing, chemically responsive layer different analyte concentrations. By using an array of such sensors different environmental parameters can be simultaneou sly determined in a complex environment; we have designed and fabricated su ch an array for the simultaneous measurement of temperature and pressure.