NimbRo Explorer: Semi-Autonomous Exploration and Mobile Manipulation in Rough Terrain

Fully autonomous exploration and mobile manipulation in rough terrain are still beyond the state of the art—robotics challenges and competitions are held to facilitate and benchmark research in this direction. One example is the DLR SpaceBot Cup 2013, for which we developed an integrated robot system to semi-autonomously perform planetary exploration and manipulation tasks. Our robot explores, maps, and navigates in previously unknown, uneven terrain using a 3D laser scanner and an omnidirectional RGB-D camera. We developed manipulation capabilities for object retrieval and pick-and-place tasks. Many parts of the mission can be performed autonomously. In addition, we developed teleoperation interfaces on different levels of shared autonomy which allow for specifying missions, monitoring mission progress, and on-the-fly reconfiguration. To handle network communication interruptions and latencies between robot and operator station, we implemented a robust network layer for the middleware ROS. The integrated system has been demonstrated at the DLR SpaceBot Cup 2013. In addition, we conducted systematic experiments to evaluate the performance of our approaches.