Semi-autonomous Coordinated Exploration in Rescue Scenarios

In this paper we study different coordination strategies for a group of robots involved in a search and rescue task. The system integrates all the necessary components to realise the basic behaviours of robotic platforms. Coordination is based on iterative dynamic task assignment. Tasks are interesting points to reach, and the coordination algorithm finds at each time step the optimal assignment of robots to tasks. We realised both a completely autonomous exploration strategy and a strategy that involves a human operator. The human operator is able to control the robots at different levels: giving priority points for exploration to the team of robots, giving navigation goal points to team of robots, and directly tele-operating a single robot. For building a consistent global map, we implemented a centralised coordinated SLAM approach that integrates readings from all robots. The system has been tested both in the UsarSim simulation environment and on robotic platforms.