Robot manipulation in cluttered environments often requires complex and sequential rearrangement of multiple objects in order to achieve the desired reconfiguration of the target objects. Due to the sophisticated physical interactions involved in such scenarios, rearrangement-based manipulation is still limited to a small range of tasks and is especially vulnerable to physical uncertainties and perception noise. This paper presents a planning framework that leverages the efficiency of sampling-based planning approaches, and closes the manipulation loop by dynamically controlling the planning horizon. Our approach interleaves planning and execution to progressively approach the manipulation goal while correcting any errors or path deviations along the process. Meanwhile, our framework allows the definition of manipulation goals without requiring explicit goal configurations, enabling the robot to flexibly interact with all objects to facilitate the manipulation of the target ones. With extensive experiments both in simulation and on a real robot, we evaluate our framework on three manipulation tasks in cluttered environments: grasping, relocating, and sorting. In comparison with two baseline approaches, we show that our framework can significantly improve planning efficiency, robustness against physical uncertainties, and task success rate under limited time budgets.
翻译:在杂乱的环境中,机器人操纵往往需要复杂和顺序地重新排列多个物体,以便实现目标物体的预期重组。由于这种情景涉及复杂的物理互动,基于重新安排的操纵仍然局限于少数的任务,特别容易受到物理不确定性和感知噪音的影响。本文件提出了一个规划框架,利用抽样规划方法的效率,通过动态控制规划视野来结束操纵循环。我们的方法是,在流程中纠正任何错误或路径偏差的同时,逐步接近操纵目标的规划和实施。与此同时,我们的框架允许在不需要明确的目标配置的情况下确定操纵目标,使机器人能够灵活地与所有目标进行互动,以便利对目标的操纵。在模拟和真实机器人方面进行广泛的实验,我们评估了我们在封闭环境中的三个操作任务的框架:掌握、迁移和排序。与两个基线方法相比,我们表明我们的框架可以大大提高规划效率,在有限的预算下,应对物理不确定性和任务成功率。