Outdoor Navigation with a Coordinated Multi-Robot System that maintains Spatial Constraints

Multi-robot systems are considered as one mean to manage large disasters like earthquakes or chemical factory incidents. Here robots can help to save lives without risking additional ones. But especially in large incidents the use of a single robot is sometimes questionable. Large groups of robots will have a much bigger impact. To gain most benefit out of such a multi-robot system the robots have to be coordinated and have to cooperate with each other. In this paper we present a coordinated navigation planning framework for a multi-robot system. This planning framework enables one person to control a complete multi-robot system. While the robots can be sent to different target positions the multi-robot system will obey predefined spatial constraints. Such spatial constraints may be to keep a communication link between the robots or to hold line-of-sight. This paper will focus on test runs in simulation and reality with this framework. We show advantages of different approaches and test the feasibility in real world environments with up to six outdoor-robots.