In applications of human-robot physical interaction, it is important to guarantee high accuracy not only in terms of the position of the end-effector, but also in terms of its orientation. While translational movements are easily understandable for a human, rotational ones do not have an immediate interpretation. This does not allow the operator to achieve an adequate positioning accuracy when a target orientation is set. In this work, a suitable strategy that facilitates the human in accomplishing rotational motion is proposed through the formulation of rotational virtual fixtures. This is obtained thanks to a clever description of the orientation that allows to draw an equivalence between the formulation of translational virtual fixtures and their rotational counterparts. To further improve the human comprehension of the best motion direction in the rotational world, a variable admittance control is also designed. We finally propose to jointly exploit these techniques to achieve the best possible performance in terms of positioning accuracy. The performance are evaluated by means of rotational point to point cooperative motions involving several subjects and an ABB IRB-140 robot.

中文翻译：

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手动引导应用中虚拟夹具和目标驱动可变导纳控制的统一方法


在人机物理交互应用中，保证末端执行器位置和方向的高精度非常重要。虽然平移运动对于人类来说很容易理解，但旋转运动却没有直接的解释。当设定目标方向时，这不允许操作员获得足够的定位精度。在这项工作中，通过制定旋转虚拟夹具，提出了一种有助于人类完成旋转运动的合适策略。这是由于对方向的巧妙描述而获得的，该描述允许在平移虚拟夹具的公式与其旋转对应物之间建立等价关系。为了进一步提高人类对旋转世界中最佳运动方向的理解，还设计了可变导纳控制。最后，我们建议联合利用这些技术，以在定位精度方面实现最佳性能。通过涉及多个受试者和 ABB IRB-140 机器人的旋转点对点协作运动来评估性能。