Planning manipulation movements of a dual-arm system considering obstacle removing

Abstract

The paper deals with the problem of planning movements of two hand-arm robotic systems, considering the possibility of using the robot hands to remove potential obstacles in order to obtain a free access to grasp a desired object. The approach is based on a variation of a Probabilistic Road Map that does not rule out the samples implying collisions with removable objects but instead classifies them according to the collided obstacle(s), and allows the search of free paths with the indication of which objects must be removed from the work-space to make the path actually valid, we call it Probabilistic Road Map with Obstacles (PRMwO). The proposed system includes a task assignment system that distributes the task among the robots, using for that purpose a precedence graph built from the results of the PRMwO. The approach has been implemented for a real dualarm robotic system, and some simulated and real running examples are presented in the paper.

Combining motion planning and task assignment for a dual-arm system

“…The use of a dual-arm robotic system is becoming quite common to perform manipulation tasks, either involving manipulation of a single object using both arms [1], [2], or manipulation of multiple objects using each arm in an independent way [3], [4].…”

“…The proposed approach follows the work in [3], which presents a variation of a probabilistic roadmaps planner to compute the robot paths and uses a precedence graph to represent the tasks to be executed by each robot arm. The nodes of the precedence graph represent the target objects and the removable objects O j , j = 1, ..., n, and the arcs represent each robot R i , i = 1, 2.…”

Comparison of motion planners in an environment with removable obstacles

“…The probabilistic roadmap [27] is a motion planner based on the classic PRM [3], but in this case the random samples are generated around a straight line in the configuration space from the initial to the goal robot configuration.…”

Simultaneous Dual-Arm Motion Planning for Minimizing Operation Time

“…Specifically, they successfully moved two robot arms simultaneously and efficiently grasped a target object from among multiple objects [4]. Although Rodriguez et al did not use dual-arm robots, they proposed a motion planning method for efficiently grasping a target object from multiple objects using multiple manipulators [5]. Moreover, Saut et al, using a dual-arm robot, proposed a method of transporting an object from one end of the workspace to the other by the handover of an object [6].…”