For the majority of tasks performed by traditional serial robot arms, such as bin picking or pick and place, only two or three degrees of freedom (DOF) are required for motion; however, by augmenting the number of degrees of freedom, further dexterity of robot arms for multiple tasks can be achieved. Instead of increasing the number of joints of a robot to improve flexibility and adaptation, which increases control complexity, weight, and cost of the overall system, malleable robots utilise a variable stiffness link between joints allowing the relative positioning of the revolute pairs at each end of the link to vary, thus enabling a low DOF serial robot to adapt across tasks by varying its workspace. In this paper, we present the design and prototyping of a 2-DOF malleable robot, calculate the general equation of its workspace using a parameterisation based on distance geometry---suitable for robot arms of variable topology, and characterise the workspace categories that the end effector of the robot can trace via reconfiguration. Through the design and construction of the malleable robot we explore design considerations, and demonstrate the viability of the overall concept. By using motion tracking on the physical robot, we show examples of the infinite number of workspaces that the introduced 2-DOF malleable robot can achieve.

中文翻译：

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可塑性机器人的设计和工作空间表征

对于传统串行机械臂执行的大部分任务，例如拣选或取放，仅需要两个或三个自由度 (DOF) 来进行运动；然而，通过增加自由度的数量，可以实现机器人手臂在执行多项任务时的灵活性。与增加机器人的关节数量以提高灵活性和适应性不同，这会增加整个系统的控制复杂性、重量和成本，可塑性机器人利用关节之间的可变刚度链接，允许每端的旋转副相对定位链接的变化，从而使低自由度串行机器人能够通过改变其工作空间来适应任务。在本文中，我们介绍了一个 2-DOF 可塑性机器人的设计和原型制作，使用基于距离几何的参数化计算其工作空间的一般方程——适用于可变拓扑的机器人手臂，并表征机器人末端执行器可以通过重新配置追踪的工作空间类别。通过可塑性机器人的设计和构建，我们探索了设计考虑因素，并展示了整体概念的可行性。通过在物理机器人上使用运动跟踪，我们展示了引入的 2-DOF 可塑性机器人可以实现的无限数量工作空间的示例。并证明整体概念的可行性。通过在物理机器人上使用运动跟踪，我们展示了引入的 2-DOF 可塑性机器人可以实现的无限数量工作空间的示例。并证明整体概念的可行性。通过在物理机器人上使用运动跟踪，我们展示了引入的 2-DOF 可塑性机器人可以实现的无限数量工作空间的示例。