S-LET复合型柔性铰链设计与性能研究

综合LET型铰链与S型铰链结构性能特点,提出了一种S-LET复合型柔性铰链,设计了该铰链的外形结构,并对其等效刚度进行分析,推导出铰链弯曲时的等效刚度计算公式。通过对不同尺寸S-LET复合型铰链弯曲等效刚度的分析,得出弯曲等效刚度修正系数,并验证了该系数的有效性。最后,通过对S型、LET型及S-LET复合型铰链弯曲变形及扭转变形的有限元仿真结果的比较,得出S-LET弯曲变形能力在S型与LET型铰链之间,而扭转变形则是三者中最小。

Design and Performance Analysis of Lamina Emergent Mechanisms S LET-shaped Flexure Hinge

Flexure hinges are significant components for achieving the action of lamina emergent mechanisms (LEMs). It has always been a challenge to design the suitable flexure hinges. The key problem is how to design and accomplish the flexible hinges with fine performance and high accuracy. Analysis on bending deformation of S-shaped flexible hinge and LET-shaped flexure hinge was compared to find a higher precision flexure hinge which was more stable in working status. A new type of flexure hinge was designed which combined the features of LET-shaped hinge with S-shaped hinge. It was named as S-LET-shaped flexure hinge. The structure of the S-LET-shaped flexure hinge was designed and the bending stiffness equivalent was presented. According to the characteristics of the bending stiffness, the bending stiffness equivalent correction coefficient of S-LET-shaped flexure hinge was proposed. By analyzing of bending equivalent stiffness for different dimensions of S-LET-shaped flexure hinges, the correction coefficient of bending equivalent stiffness was obtained and the effectiveness of bending equivalent stiffness was verified. Finally, the results of the finite element simulation of hinge bending deformation and torsion deformation were compared among S-shaped, LET-shaped and S-LET-shaped hinges. The bending deformation capacity of S-LET-shaped hinge was between S-shaped and LET-shaped hinges and the torsional deformation capacity of S-LET-shaped hinge was the smallest among the three kinds of hinges.