During physical human robot collaboration, it is important to be able to implement a time-varying interactive behaviour while ensuring robust stability. Admittance control and passivity theory can be exploited for achieving these objectives. Nevertheless, when the admittance dynamics is time-varying, it can happen that, for ensuring a passive and stable behaviour, some spurious dissipative effects have to be introduced in the admittance dynamics. These effects are perceived by the user and degrade the collaborative performance. In this paper we exploit the task redundancy of the manipulator in order to harvest energy in the null space and to avoid spurious dynamics on the admittance. The proposed architecture is validated by simulations and by experiments onto a collaborative robot.

翻译：在人类物理机器人协作期间,必须能够实施时间变化式互动行为,同时确保稳健稳定。可以利用接受控制和被动理论来实现这些目标。然而,如果接受动力是时间变化式的,那么,为了确保被动和稳定行为,可以在接受动力中引入一些虚假的消散效应。这些效应为用户所理解,并降低协作性能。在本文中,我们利用操纵者的任务冗余,以便在空空空空间中收获能量,避免在接纳上出现虚假动态。提议的建筑通过模拟和实验对协作机器人进行验证。