Search

The performance of quartz crystal resonator (QXR) force sensors, which utilize symmetrical incomplete circular QXR's as indicative factors are affected by transverse force. However, the main focus of the effect of transverse force is mainly on the two types of QXR force sensors that are sensitivity and linearity.

Changes in the resonance frequencies of thickness-shear vibration of symmetrical incomplete circular AT-cut quartz crystal resonators (QXR), used as sensing elements in digital force sensors or pressure transducers, are discussed. Changes are brought about by application of diametrical forces, and piezoelectric effects and anisotropic characteristics of crystal plates are examined.

A multi-resolution wireless force sensing system, including a passive time-delay surface acoustic wave (SAW) device and a specific interrogation unit, is described. An interdigital transducer (IDT) is used as the force sensing element, transducing electromagnetic waves into surface acoustic waves and vice versa.