Hussein Hussein, Wang Chen, Amendoeira Esteves Rui, Kraft Michael, Fariborzi Hossein
Department of Mechanical Engineering, MSFEA, American University of Beirut, Beirut, 1107 2020 Lebanon.
King Abdullah University of Science and Technology, Thuwal, 23955-6900 Saudi Arabia.
Microsyst Nanoeng. 2024 Mar 22;10:43. doi: 10.1038/s41378-024-00657-w. eCollection 2024.
Pre-shaped microbeams, curved or inclined, are widely used in MEMS for their interesting stiffness properties. These mechanisms allow a wide range of positive and negative stiffness tuning in their direction of motion. A mechanism of pre-shaped beams with opposite curvature, connected in a parallel configuration, can be electrothermally tuned to reach a near-zero or negative stiffness behavior at the as-fabricated position. The simple structure helps incorporate the tunable spring mechanism in different designs for accelerometers, even with different transduction technologies. The sensitivity of the accelerometer can be considerably increased or tuned for different applications by electrothermally changing the stiffness of the spring mechanism. Opposite inclined beams are implemented in a capacitive micromachined accelerometer. The measurements on fabricated prototypes showed more than 55 times gain in sensitivity compared to their initial sensitivity. The experiments showed promising results in enhancing the resolution of acceleration sensing and the potential to reach unprecedent performance in micromachined accelerometers.
预成型的微梁，无论是弯曲的还是倾斜的，因其有趣的刚度特性而在微机电系统（MEMS）中得到广泛应用。这些机构在其运动方向上允许进行广泛的正刚度和负刚度调谐。一种具有相反曲率的预成型梁机构，以平行配置连接，可以通过电热调谐，在制造位置达到接近零或负刚度行为。这种简单的结构有助于将可调弹簧机构纳入不同设计的加速度计中，即使采用不同的传感技术。通过电热改变弹簧机构的刚度，加速度计的灵敏度可以显著提高或针对不同应用进行调谐。在电容式微机械加速度计中采用了相反倾斜的梁。对制造的原型进行的测量表明，与初始灵敏度相比，灵敏度提高了55倍以上。实验在提高加速度传感分辨率以及在微机械加速度计中实现前所未有的性能方面显示出了有前景的结果。
