剪切型阻尼U型柔性铰链设计与实验分析

根据柔性铰链的无阻尼结构特点,并利用黏弹性阻尼材料的剪切损耗特性,提出一种剪切型阻尼U型柔性铰链的结构模型,并结合GHM(Goulla-Hughes-MacTavish,简称GHM)黏弹性理论模型建立带阻尼铰链动力学方程。该铰链通过提高外加黏弹性阻尼层材料的剪切效应,达到增强结构阻尼目的。为了测试剪切型阻尼结构对该U型铰链的振动抑制效果,对其进行自由振动信号测试和动态力学分析(dynamic mechanical analysis,简称DMA)实验。结果显示,该阻尼结构能使铰链结构在120~150Hz的共振频段内因振幅增大,阻尼层剪切效应加剧,出现明显的阻尼损耗峰值,有效增强了铰链的结构阻尼。

Design and Experimental Analysis of U-shaped Flexure Hinge with Shearing Damping

Flexible mechanism can transfer or transform the motion, force and energy through the elastic deformation of flexure hinge. This paper propose a novel structural model for U-shaped flexure hinge with large damping based on the damping-free property of flexure hinge and the loss modulus characteristic caused by the shear of viscoelastic damping material. Combined with GHM (Goulla-Hughes-Mactavish) viscoelastic model, a pseudo-rigid-body model with damping hinge is also introduced.The structural damping property of the flexure hinge could be highly strengthened with the help of the shearing effect of viscoelastic damping material. To identify the vibration suppression effect of damping structure for the U-shaped flexure, this paper measured the free vibration signal and conduct the experiments of DMA (dynamic mechanical analysis). The results show that damping loss peak appear in the frequency range of 120~150 Hz through the damping structure design, which effectively enhanced the structural damping property of the flexure hinge.