梯形变截面悬臂梁式微质量传感器设计与分析

针对微小集中质量测量问题,提出并制备了一种梯形变截面悬臂梁式微质量传感器,建立了梯形变截面悬臂梁式微质量传感器的振动分析模型。采用有限元方法求解其振动控制方程,获得了微质量传感器的灵敏度。仿真分析结果表明,相对于等截面矩形悬臂梁式微质量传感器,单层压电和双层压电结构的变截面悬臂梁传感器的灵敏度分别提高了127.00%和263.00%。采用线切割工艺,加工制备了单压电层梯形变截面结构的微质量传感器并对传感器进行了实验测试,在误差允许范围内,仿真结果与实验结果基本一致,验证了采用梯形变截面悬臂梁式结构可以有效的提高传感器的灵敏度。

Design and analysis of micro-mass sensor based on trapezoidal variable cross-section cantilever

In this paper, a trapezoidal variable cross-section cantilever sensor was designed and fabricated for measuring small lumped masses, and the dynamic vibration model in the form of second order differential equation with variable coefficients is established. The corresponding mass sensitivity was obtained by finite element method. Comparing with the rectangular constant cross-section type, the sensitivities of the proposed mass sensors with single PZT layer and double PZT layers are improved by 127.00% and 263%, respectively. By utilizing wire cutting technology, a trapezoidal variable cross-section cantilever sensor was designed and fabricated which is comprised of one PZT layer bonding to the elastic cantilevers for self-exciting. Finally, the feasibility of introducing trapezoidal variable cross-section cantilever to improve the sensitivity was validated by the experimental results. Additionally, the mass detecting sensitivity can be improved by adjusting the changing rate of the cantilever cross-section.