Self-excited Oscillation for High-viscosity Sensing and Self-excited Coupled Oscillation for Ultra-senseitive Mass Sensing

In the paper, we introduce the applications of self-excited oscillation to high-viscosity sensing and mass-sensing. Vibration-type sensing allows us to do the instantaneous and continuous measurements of changes in viscosity, mass and so on occurring with time. In the usual procedure, the external or forced excitation has been employed to the resonators. The viscosity sensing is carried out by using the change of the resonance amplitude in the frequency response curve, i.e., Q factor, depending on the viscosity. The mass sensing is carried out by using the shift of the resonance frequency corresponding to the natural frequency, depending on the mass. In order to realize the high-viscosity sensing and the mass-sensing in viscosity environments, we introduce the application of self-excited oscillation as an excitation method.