Zhang Tongtian, Wu Junhui, Zhou Guangya
Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore.
Micromachines (Basel). 2025 Mar 28;16(4):397. doi: 10.3390/mi16040397.
MEMS stiffness-tunable devices, owing to their low resonant frequency and high sensitivity, have been widely adopted in fields such as biological force sensing, vibration sensing, and inertial sensing. However, traditional stress-effect-based stiffness-adjustment methods offer limited tuning range. This paper introduces a novel stiffness-tuning mechanism based on the principle of stiffness compensation, integrating positive stiffness springs with V-shaped negative stiffness springs in a parallel configuration. A self-locking mechanism enables precise control of the mechanical preloading on the negative stiffness structures to realize stiffness adjustment. This design is prototyped by microscale fabrication techniques and is suitable for miniaturization. The experimental results confirm a stiffness reduction of over 90% and demonstrate bistability. These findings highlight the potential of the design for high-sensitivity MEMS accelerometers and dual-mode optical switches with low switching voltage.
微机电系统（MEMS）刚度可调装置由于其低谐振频率和高灵敏度，已在生物力传感、振动传感和惯性传感等领域得到广泛应用。然而，传统的基于应力效应的刚度调节方法的调节范围有限。本文介绍了一种基于刚度补偿原理的新型刚度调节机制，将正刚度弹簧与V形负刚度弹簧以并联配置集成在一起。一种自锁机制能够精确控制负刚度结构上的机械预载，以实现刚度调节。该设计通过微尺度制造技术制作成原型，适用于小型化。实验结果证实刚度降低超过90%，并展示了双稳态。这些发现突出了该设计在高灵敏度MEMS加速度计和低开关电压双模式光开关方面的潜力。
