新型变厚度柔性铰链的设计与研究

Design and Research on Variable Thickness Flexure Hinge

针对传统的直梁型柔性铰链转动精度低的缺点,本文提出一种新型的变厚度柔性铰链,使得该铰链的变形主要集中在铰链的中心位置,以此提高柔性铰链的转动精度。为了研究变厚度柔性铰链,首先列出变厚度柔性铰链的厚度公式,然后以Euler⁃Bernoulli梁理论为基础,搭建出变厚度柔性铰链的力学模型,并通过牛顿迭代法进行具体数值求解,为了验证力学模型的正确性,将铰链模型导入有限元仿真软件ABAQUS中进行静力学仿真,验证了力学模型的正确性;基于力学模型与有限元仿真,研究了变厚度柔性铰链的变形特性与圆弧半径r之间的关系,通过分析结果表明,变厚度柔性铰链相对传统的直梁型柔性铰链具有较大的转角范围和更小的中心轴漂n,以本文提出的变厚度柔性铰链为基本单元,搭建出具备大转角能力的柔性转动铰链,为需要大转角、大承载能力的仿生关节的设计提供一定的理论参考。

The traditional straight beam flexure hinge often has low rotation accuracy,this paper presents a new type of flexible hinge with variable thickness,the new hinge deformation is mainly concentrated in the center of the hinge,so as to improve the rotational accuracy of the flexure hinge.Firstly,the thickness formula of variable thickness flexure hinge is listed.Then,based on Euler⁃Bernoulli beam theory,the mechanical model of variable thickness flexure hinge is established,and the numerical solution is carried out with Newton iteration method.In order to verify the correctness of the mechanical model,the hinge model is imported into the finite element simulation software ABAQUS for static simulation,and the correctness of the mechanical model is verified.Based on the mechanical model and finite element simulation,the relationship between the deformation characteristics of variable thickness flexure hinge and the arc radius r is studied.The results show that compared with the traditional straight beam flexure hinge,the variable thickness flexure hinge has larger angle range and smaller center axis drift n.Taking the variable thickness flexure hinge proposed in this paper as the basic unit,a flexible rotating hinge with large turning angle is built,which provides a theoretical reference for the design of bionic joint with large rotation angle and large bearing capacity.