Structural Application of Sealant to Make Flexible Joint System and Behavior of Joint

本文研究了由各种矩形截面的密封胶制成的柔性接头，所得结果如下。(1)接头材料的弹性模量和焊缝形状是影响接头力学性能的主要因素。对于后者，在拉伸和压缩变形中，在焊道中产生的应力取决于深度（D）/宽度（W）的比值，在弯曲变形中，取决于D^2/W的比值。但是，没有观察到的形状依赖性的剪切变形。(2)胎圈变形时的应力分布胎圈横截面上的应力从中心向角部逐渐增大。(3)接头材料的抗疲劳性疲劳过程中，焊缝表面靠近基体的两端出现裂纹，直到裂纹出现的循环次数（N）可用下式表示：log N = -A log（D^n/W）+ B：其中A和B为常数。(4)柔性节点二维结构的荷载-变形关系除了节点材料的弹性模量外，节点的形状对结构的刚度有很大的影响。随着D的增加或W的减小，结构变得更加刚性。(5)基于以上研究的知识，开发了一种新型的高自由度柔性关节系统，并对该系统的性能进行了研究。

Flexible joints made of sealants with various rectangular cross sections were investigated, and the results obtained are as follows.(1) Mechanical behavior of a joint with various cross sections Mechanical behavior of a joint was mainly affected by modulus of a joint material and the shape of a bead. As for the latter, stress induced in a bead is depend on the ratio such as depth(D)/width(W) in tensile and compressive deformation, D^2/W in bending deformation. But, no dependence to the shape was observed in shearing deformation.(2) Stress distribution in a bead deformed Stress in cross sectional area of a bead is gradually increasing from the center to the corner.(3) Fatigue resistance of joint materials Cracks appeared at the both ends, near substrate, on the surfaces of a bead during fatigue operation, and the number of cycles till cracking (N) can be expressed the next equation , log N = -A log ( D^n/W ) + B :where A and B are constants.(4) Load-deformation relation of a two dimensional structure with flexible joints Rigidity of a structure is much affected by the shape of a bead in addition to the modulus of a joint material. The structure becomes more rigid according to an increase of D or a decrease of W.(5) Development of a new flexible joint system Based on the knowledge studied above, a new flexible joint system with higher degree of freedom was developed, and the behavior of the system was investigated.