Wu Haitao, Lai Leijie, Zhu Limin
College of Mechanical and Automotive Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Rev Sci Instrum. 2021 May 1;92(5):055109. doi: 10.1063/5.0047420.
In this paper, an analytical model of elliptical bridge-type compliant mechanism is established. Compared with the traditional bridge mechanism, the elliptical bridge-type compliant mechanism has the advantages of light weight, high natural frequency, and more uniform stress distribution. Based on the strain energy and Castigliano's displacement theorem, a static model for calculating the displacement amplification ratio and input stiffness is established. Then, the Lagrange equation is used to establish the dynamic model to calculate the natural frequency. After that, finite element simulation and experimental test are both used to verify the proposed analytical model. The results show that the maximum error between the analytical model and finite element simulation is within 8.25% and that of the experimental results is within 6.25%. The conclusion of this paper provides an accurate prediction analytical method for the mechanical performance index design of the elliptical compliant mechanism, which has important theoretical significance.
本文建立了椭圆桥式柔顺机构的解析模型。与传统桥式机构相比，椭圆桥式柔顺机构具有重量轻、固有频率高、应力分布更均匀等优点。基于应变能和卡斯蒂利亚诺位移定理，建立了用于计算位移放大比和输入刚度的静态模型。然后，利用拉格朗日方程建立动态模型来计算固有频率。之后，通过有限元模拟和实验测试对所提出的解析模型进行验证。结果表明，解析模型与有限元模拟之间的最大误差在8.25%以内，与实验结果的最大误差在6.25%以内。本文的结论为椭圆柔顺机构的力学性能指标设计提供了一种准确的预测分析方法，具有重要的理论意义。
