Microsystems Technology Group, Institute of Micro- and Nanotechnologies MacroNano®, Technische Universität Ilmenau, Max-Planck-Ring 12, 98693 Ilmenau, Germany.
Force Measurement and Weighing Technology Group, Institute of Process Measurement and Sensor Technology, Technische Universität Ilmenau, Gustav-Kirchhoff-Str. 1, 98693 Ilmenau, Germany.
Sensors (Basel). 2023 Mar 22;23(6):3342. doi: 10.3390/s23063342.
In this paper, a miniaturized weighing cell that is based on a micro-electro-mechanical-system (MEMS) is discussed. The MEMS-based weighing cell is inspired by macroscopic electromagnetic force compensation (EMFC) weighing cells and one of the crucial system parameters, the stiffness, is analyzed. The system stiffness in the direction of motion is first analytically evaluated using a rigid body approach and then also numerically modeled using the finite element method for comparison purposes. First prototypes of MEMS-based weighing cells were successfully microfabricated and the occurring fabrication-based system characteristics were considered in the overall system evaluation. The stiffness of the MEMS-based weighing cells was experimentally determined by using a static approach based on force-displacement measurements. Considering the geometry parameters of the microfabricated weighing cells, the measured stiffness values fit to the calculated stiffness values with a deviation from -6.7 to 3.8% depending on the microsystem under test. Based on our results, we demonstrate that MEMS-based weighing cells can be successfully fabricated with the proposed process and in principle be used for high-precision force measurements in the future. Nevertheless, improved system designs and read-out strategies are still required.
本文讨论了一种基于微机电系统（MEMS）的小型称重单元。基于 MEMS 的称重单元的灵感来自宏观电磁力补偿（EMFC）称重单元，并且分析了一个关键系统参数，即刚度。首先使用刚体方法对运动方向上的系统刚度进行了分析评估，然后使用有限元法进行了数值建模以进行比较。已经成功地微加工了基于 MEMS 的称重单元的原型，并且在整体系统评估中考虑了制造过程中出现的系统特性。通过使用基于力-位移测量的静态方法，实验确定了基于 MEMS 的称重单元的刚度。考虑到微加工称重单元的几何参数，所测量的刚度值与计算的刚度值相匹配，偏差在-6.7%到 3.8%之间，具体取决于测试的微系统。基于我们的结果，我们证明了可以使用所提出的工艺成功地制造基于 MEMS 的称重单元，并且原则上可以在未来用于高精度力测量。然而，仍需要改进系统设计和读取策略。
