Uhura: a Software Framework for Swarm Management in Multi-Radio Robotic Networks

In a swarm of unmanned aerial (UAVs) or ground vehicles (UGVs), nodes can autonomously coordinate their activities and cooperate to accomplish a given task as for instance the data exchange with Internet of Things (IoT) devices. However, due to the unpredictable environmental conditions, wireless communication on the air-to-air, ground-to-air and ground-to-ground links can experience completely different channel conditions. For this reason, several Machine-to-Machine (M2M) communication technologies have been proposed with different Quality of Service (QoS) characteristics in terms of range, bandwidth and energy consumption profile: at the same time, new challenges have arisen from the integration or joint utilization of multiple M2M stacks in heterogeneous robotic environments. In this work, we address such challenges through the design and development of a new framework, called Uhura, that eases the interaction among heterogeneous devices e.g., aerial platforms, ground vehicles, robots, sensors, and more. The Uhura framework provides communication facilities for swarm of UAVs/UGVs by abstracting from the underlying M2M technologies; in addition, it supports automatic selection of the M2M stack on multi-adapter UAVs/UGVs based on QoS requirements of the application. In this paper, we describe the Uhura architecture and its ROS-based implementation. Also, we report some results of two real-world experiments involving (i) a small swarm of UAVs and (ii) a multiadapter UAV communicating to a ground IoT gateway.