A Chipless Piezoresistive Strain Sensor

Strain sensors are widely used in various applications and, depending on the specific application, it is necessary they operate completely wireless. The first step for the realization of a wireless strain sensor is the choice of the transducing material. Piezoresistive materials, whose surface impedance varies when a mechanical stimulus is applied, are suitable candidates for fabricating a strain sensor. Here an innovative and simple wireless strain sensor is proposed which exploits the intrinsic properties of piezoresistive materials combining with a suitably designed frequency selective surface.