基于高阶多模态可调机理的MEMS静电谐振器及谐振式传感器研究

MEMS electrostatic resonators and resonant sensors have better performance when they work at higher modes, but higher modes are difficult to be excited, detected and tuned. In this project, resonators with higher-multi modes and adjustable mechanism are proposed, Based on the mechanism, resonant sensors (accelerometer and electrometer) with adjustable sensitivity, high resolution and large dynamic range are studied. The project includes three scopes: (1) investigating electrodes configuration and multi-node excitation and detection, building models for parametric excited vibration, analyzing coupling effect between multi modes, proposing selectable excitation and switching control strategy; (2) investigating nonlinear dynamic characteristics of each mode of the resonator, and seeking method of eliminating nonlinearity in amplitude-frequency for high modes; (3) designing sensitivity-adjustable resonant accelerometers and electrometers based on the higher-multi modes resonator, studying sensing mechanism to input force for the resonant element, revealing influence rule of mode order on sensitivity, resolution and range of the sensors, putting forward a control strategy of mode switching and sensitivity gradient, establishing optimal strategy of multi thresholds for acceleration and charge detection. The project achievements provide theoretical guidance and technical support for the realization of broadband modulation resonators and resonant sensors with high sensitivity, high resolution and large dynamic range.

MEMS静电谐振器及谐振式传感器工作在高阶模态时有更好的性能，但高阶模态难以被激励、检测和调制。本项目提出谐振器的高阶多模态可调机理，并基于该机理研究高分辨率、大量程的灵敏度可调谐振式传感器（加速度计和静电计）。研究内容包括:(1)研究谐振器的电极配置方法及多点激振和检测机制，建立高阶模态多点参激振动的力学模型，分析多模态耦合效应，提出多模态的可选择性激振和切换控制策略；(2)研究谐振器各阶模态的非线性动力学特征，探索高阶模态振幅-频率非线性的消除方法；(3)基于高阶多模态谐振元件设计灵敏度可调谐振式加速度计和静电计，研究谐振元件对外部输入力的敏感机制，揭示模态阶数对传感器灵敏度、分辨率、量程的影响规律，提出模态切换与灵敏度梯度的控制策略，建立多阈值加速度、电荷检测的最优策略。本项目成果为实现宽频调制谐振器，以及高分辨率、大量程的灵敏度可调谐振式传感器供理论指导和技术支持。