Local Path Replanning for Unforeseen Obstacle Avoidance by Autonomous Sweeping Robots

In this paper, we propose a planning algorithm for sweeping tasks in environments with unforeseen obstacles. Sweeping means a motion that a robot covers a 2-dimensional area. When a mobile robot finds an unforeseen obstacle, it has to not only avoid collision but also sweep the whole area including where the obstacle is located. In the proposed algorithm, a robot determines local area where sweeping path should be arranged based on it's limited sensing ability. The algorithm avoids heavy calculation cost by limiting the planning area. A robot minimizes length of path when it connects path inside and outside the local area. An autonomous mobile robot can omit running time by the algorithm. We verify the efficiency of the algorithm and discuss the trade-off between running time and sensing/calculation time by simulations and experiments.