Synchronous mass detection based on 1:1:2 internal resonance of piezo-driven resonator

The bifurcation-based mass sensor can take advantage of amplitude jumps between multiple steady states to realize quantitative mass detection and mass warning. Compared with the classical detection based on the frequency shift induced by an added mass, sudden jumps in amplitude make the detection of a very small mass possible. Most research has been focused on the mass detection of a single analyte, but less research has been done on the detection of double analytes. In this study, the concept of synchronous mass detection for double analytes based on bifurcation induced by 1:1:2 internal resonance is first proposed and verified experimentally. Firstly, a piezo-driven three-degree-of-freedom (3-DOF) magnetic coupling resonant structure with the potential of 1:1:2 internal resonance is designed. Through driving the high-frequency resonant beam, the parametric vibration of two low-frequency resonant beams is realized, which causes the modal coupling vibration phenomenon in the three frequency intervals. The physical conditions of multi-mode coupling vibration are also deduced theoretically. Typically, by measuring the shifts of the upper and the lower critical bifurcation frequencies, the quantitative mass detection of the double analytes can be carried out simultaneously. Beside, a conceptual scheme with multiple mass warnings for double analytes is also creatively proposed. The experimental results show that with the increase of the adsorption mass, the resonant amplitude of the system obviously changes near the equilibrium point, accompanied by a bifurcation phenomenon. The research results provide a systematic framework for the development of resonant mass sensing devices based on multi-mode coupled vibration.