M. Sc. Frank Engelhardt

Wireless Mesh Networks (WMNs) provide a promising foundation for a flexible and reliable communication infrastructure in industrial environments. Meeting the QoS demands of real-time applications, though, requires the deployment of various advanced mechanisms. Compared to wired networks, applications face higher packet loss rates in wireless networks due to the inherent unreliability of wireless communication. Furthermore, if mobile stations are involved, links that fail due to node movement frequently cause packet losses. In this paper, we present an approach to tolerate those specific losses by locally recovering lost packets and transiently re-routing them over an alternative path. The evaluation in real-world experiments shows that we can completely prevent packet loss without significantly increasing the end-to-end latency. This allows the deployment of WMNs for real-time applications without explicitly considering the increased error-proneness of wireless communication and station mobility.

Kurzfassung
Die Fähigkeit eines autonomen mobilen Roboters, während der Fahrt seine Umgebung zu kartieren, eröffnet ihm ein weites Spektrum von Anwendungen. In dieser Arbeit wird ein Online-SLAM-Verfahren präsentiert, das auf dem cRIO-Echtzeitsystem des Roboters VolksBot-Lab lauffähig ist und bei Indoor-Szenarien sowohl im Zeitverhalten als auch in der Kartenqualität sehr zuverlässige Ergebnisse liefert. Das Robotersystem kommt derzeit im Rahmen einer Lehrveranstaltung der Universität Magdeburg zum Einsatz.

Abstract
The ability of an autonomous mobile robot to explore and map its environment during operation opens a variety of applications. In this paper we present an online-SLAM solution, which runs on the cRIO realtime controller of the robot VolksBot-Lab. It provides reliable results in both its map quality and timing behavior concerning indoor scenarios. The robot is currently used within the scope of a student project at the University of Magdeburg.

@inproceedings{VIP2011,
  author = {Frank Engelhardt and Timo Lindhorst and Ansgar Bredenfeld},
  title = {{Umsetzung eines Online-SLAM-Verfahrens auf der Roboterplattform VolksBot-Lab}},
  booktitle = {{Virtuelle Instrumente in der Praxis 2011}},
  publisher = {VDE Verlag},
  year = {2011},
  month = {September}
}