Planning motions to grasp an object in cluttered and uncertain environments is a challenging task, particularly when a collision-free trajectory does not exist and objects obstructing the way are required to be carefully grasped and moved out. This letter takes a different approach and proposes to address this problem by using a randomized physics-based motion planner that permits robot-object and object-object interactions. The main idea is to avoid an explicit high-level reasoning of the task by providing the motion planner with a physics engine to evaluate possible complex multibody dynamical interactions. The approach is able to solve the problem in complex scenarios, also considering uncertainty in the objects' pose and in the contact dynamics. The work enhances the state validity checker, the control sampler, and the tree exploration strategy of a kinodynamic motion planner called KPIECE. The enhanced algorithm, called p-KPIECE, has been validated in simulation and with real experiments. The results have been compared with an ontological physics-based motion planner and with task and motion planning approaches, resulting in a significant improvement in terms of planning time, success rate, and quality of the solution path. Index Terms-Motion and path planning, manipulation planning, physics-based planning, planning under uncertainties.
To deal with grasping an object in cluttered and uncertain environments, Moll et al. raise a rearrangement method to make space for the gripper to reach and grasp the target REF .
Randomized Physics-Based Motion Planning for Grasping in Cluttered and Uncertain Environments
IEEE Robotics and Automation Letters
IEEE Robotics and Automation Letters
Computer Science Engineering Physics