Two-Layers Workspace: A New Approach to Cooperative Object Transportation With Obstacle Avoidance for Multi-Robot System

In this paper we present a new approach to cooperative overhead object transportation with obstacle avoidance for multi-robot systems. This approach considers situations in which there are obstacles that only pose a risk to the robots involved in the transport and not necessarily to the group of robots with the load. Thus, we propose to separate the workspace into two layers in a way that the obstacles which only pose risk of collision to the robots can be transposed by a local planner. This new approach to the load transportation problem allows the system to find shorter paths or even find a solution in situations which would not be possible with the classic approach. Furthermore, the developed method has a configuration space independent of the number of robots and it is robust to environmental variation, not reducing its performance in more complex environments as in narrow passages or long corridors. The proposed approach was tested by simulation and the results are compared to the classic one.