Multi Fields Coupled Dynamics Character Research Of Micro Resonant Gas Sensor

Sensor technology is referred to as one of the three pillars of the modern information technology. Micro resonant gas sensor has broad application prospects in consumer electronics industry, automobile industry, aerospace, chemical, medical industry and other fields because of the advantages such as small size, simple structure, high sensitivity and good reliability. In this paper, multi-field coupled vibration characteristics of micro resonator gas sensor is studied, the design and manufacturing of the sensor is done with MEMS technology, and test of the sensor are completed.Firstly, the mechanical, chemical and molecular force coupled dynamics model of micro resonator gas sensor is established, and the dynamics equation of free vibration is deduced. The expression of instantaneous frequency is calculated by Multi-scale method, and the effects of main system parameters on natural frequency and instantaneous frequency are analyzed.Secondly, the mechanical, electrical, chemical and molecular force coupled dynamics model is established, and the dynamics equation of free vibration and forced vibration is deduced. The expression of instantaneous frequency is given, and the effects of electric field force on natural frequency and instantaneous frequency and the interaction between field are analyzed.Using Taylor series expansion, nonlinear term to the molecular force and electric field force is added, and the nonlinear natural frequency and instantaneous frequency of micro resonator gas sensor is calculated. The nonlinear error and the nonlinear dynamic characteristics of the sensor are analyzed.The micro resonator gas sensor is manufactured with MEMS technology. Its natural frequency and instantaneous frequency are detected and the influence of molecular force on natural frequency is verified by the test system. The experimental phenomena is analyzed, and the theoretical analysis is illustrated.