Abstract This paper proposes a rigid–flexible coupling parallel mechanism with variable stiffness based on a novel 3-5R parallel mechanism, which is derived from a special form of anti-parallelogram mechanism. A spring is used as the fourth limb of the 3-5R parallel mechanism to endow the mechanism with elasticity, and then the motion of the 3-5R parallel mechanism is accompanied by the spring's length and curvature. Four driving cables are installed to actuate the mechanism, and the elastic spring limb makes the stiffness of the mechanism adjustable. The working process, kinematics, and stiffness of the proposed mechanism are analyzed, the lateral flexion of the spring and rigid–flexible coupling of the mechanism are also studied. Finally, a physical prototype is fabricated, the motion trajectory and stiffness of the moving platform are tested to show the feasibility of the proposed mechanism.

中文翻译：

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变刚度索驱动刚柔耦合并联机构的设计与分析

摘要 本文基于一种新颖的3-5R并联机构，提出了一种变刚度刚柔耦合并联机构，该并联机构源自一种特殊形式的反平行四边形机构。弹簧作为3-5R并联机构的第四臂，赋予该机构弹性，然后3-5R并联机构的运动伴随着弹簧的长度和曲率。装有四根驱动拉索驱动机构，弹性弹簧臂使机构刚度可调。分析了所提出机构的工作过程、运动学和刚度，还研究了弹簧的横向弯曲和机构的刚柔耦合。最后，制造了一个物理原型，