Design and Experiment of Mass Warning Resonant Sensor Induced by Modal Coupling

A new mass warning scheme via integrating modal coupled vibration of T-type resonant sensor is proposed in this paper, which can utilize the amplitude jump induced by mass perturbation to achieve the first and second mass warnings. A T-type resonant sensing structure with 1:2 internal modal coupling is designed and its coupling dynamic behavior is experimentally measured. Then, the theoretical expression is established and derived by Hamilton’s principle and multi-scale method to predict the amplitude-frequency curve with respect to the effect of mass perturbation. Besides, the physical conditions of modal coupled vibration under different perturbation masses are obtained. The working range of the resonant mass sensor is investigated by bifurcation analysis. Both theoretical and experimental results show that when the driving frequency is slightly greater than the upper critical frequency of the modal coupled vibration of the resonator, the resonant sensor has the first mass warning and the second mass warning with the increase of the perturbation mass.