In robotic manipulation, end-effector compliance is an essential precondition for performing contact-rich tasks, such as machining, assembly, and human-robot interaction. Most robotic arms are position-controlled stiff systems at a hardware level. Thus, adding compliance becomes essential. Compliance in those systems has been recently achieved using Forward dynamics compliance control (FDCC), which, owing to its virtual forward dynamics model, can be implemented on both position and velocity-controlled robots. This paper evaluates the choice of control interface (and hence the control domain), which, although considered trivial, is essential due to differences in their characteristics. In some cases, the choice is restricted to the available hardware interface. However, given the option to choose, the velocity-based control interface makes a better candidate for compliance control because of smoother compliant behaviour, reduced interaction forces, and work done. To prove these points, in this paper FDCC is evaluated on the UR10e six-DOF manipulator with velocity and position control modes. The evaluation is based on force-control benchmarking metrics using 3D-printed artefacts. Real experiments favour the choice of velocity control over position control.
翻译:在机器人操作中,终端效应合规性是完成诸如机械、组装和人-机器人互动等接触丰富任务的必要先决条件。大多数机器人武器都是硬件级的定位控制硬系统。因此,增加合规性变得至关重要。这些系统的合规性最近已经使用远方动态合规性控制(FDCCC)实现。 由于其虚拟前方动态性能模式,该系统可以在位置和速度控制机器人上同时实施。本文件评估了控制接口(因而也是控制域)的选择,尽管这些接口被认为微不足道,但因其特性不同而必不可少。在某些情况下,这种选择仅限于现有的硬件界面。然而,由于选择,基于速度的控制界面可以更顺利地进行合规性控制,互动力减少,而且工作已经完成。为了证明这些点,FDCC在本文中用速度和位置控制模式对UR10e 6-DOF 操纵器进行了评价。评价基于使用3D打印的手工艺品的强制控制基准指标。实际实验有利于选择对位置控制进行速度控制。