Abstract A variable stiffness mechanism (VSM) is used to connect the principal motor and the load of a serial-configuration variable stiffness actuator (VSA) and can adjust the intrinsic stiffness of the VSA to improve the dynamic performance, energy efficiency, and safety of robotic systems. This paper presents a new configuration synthesis method to design VSMs based on guide-bar mechanisms through the addition of linear springs and the use of length-adjustable links. The springs are used to constrain the mechanism and generate compliant behaviour, and the length-adjustable links are used to adjust the transmission ratio and modulate the apparent stiffness. The conditions for designing VSMs with symmetrical stiffness characteristics, capable of low-power cost stiffness modulation and decoupled control of equilibrium position and stiffness, are also derived. By selecting different spring-constrained joints, length-adjustable links, initial angles of input joints, and length ranges of the adjustable links, twelve energy-efficient VSMs with different stiffness performance are constructed. In addition, the concept design of a VSA that can vary its stiffness from zero to infinity is presented; this design uses only one linear torsion spring without a preload.

中文翻译：

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基于带长度可调连杆的导杆机构的变刚度机构构型综合

摘要 变刚度机构（VSM）用于连接串联配置的变刚度执行器（VSA）的主电机和负载，可以调节VSA的固有刚度，以提高动力性能、能效和安全性。机器人系统。本文提出了一种新的配置综合方法，通过添加线性弹簧和使用长度可调连杆来设计基于导杆机构的 VSM。弹簧用于约束机构并产生柔顺行为，长度可调连杆用于调节传动比和调节表观刚度。设计具有对称刚度特性的 VSM 的条件，能够低功耗成本刚度调制和平衡位置和刚度的解耦控制，也是衍生出来的。通过选择不同的弹簧约束关节、长度可调连杆、输入关节的初始角度和可调连杆的长度范围，构建了十二种具有不同刚度性能的节能VSM。此外，还介绍了刚度从零到无穷大变化的 VSA 的概念设计；这种设计仅使用一个线性扭力弹簧，没有预紧力。