UAV Networks in Rescue Missions Mahdi Asadpour, Domenico Giustiniano, Karin Anna Hummel, Simon Egli ETH Zurich, Communication Systems Group Zurich, Switzerland {mahdi.asadpour,domenico.giustiniano,karin.hummel,simon.egli}@tik.ee.ethz.ch ABSTRACT Small-scale unmanned aerial vehicles (UAVs) have received high attention by the robotics community for delivering sen- sory data of limited size. Yet, the communication capabil- ities of off-the-shelf UAVs are insufficient for high volume data, such as images and videos. In this demo, we present our networking solution to this problem, residing next to the auto-pilot, and able to create an ad-hoc multi-hop network of UAVs. We show the effectiveness of our implementation in two representative scenarios of rescue missions: (i) the es- tablishment of end-to-end connectivity for a smartphone in an area with network outage and (ii) the delivery of a high- resolution video of a supervised area from a flying UAV to the ground station. Categories and Subject Descriptors C.2.1 [Computer-Communication Networks]: Network Architecture and Design—Wireless communication Keywords Unmanned Aerial Vehicles, 802.11n, Aerial Links 1. INTRODUCTION Unmanned aerial vehicles (UAVs) play an increasingly im- portant role in time-critical search and rescue (SAR) mis- sions. Here, UAVs can provide a swift first overview of the target area for 3D mapping or spot a missing person. This is viable, as state-of-the art UAVs can have an optional light- weight high-resolution camera [4]. However, this large-size data cannot be delivered in real-time by means of, e.g., the 802.15.4 communication protocol used in modern solutions to control the UAVs. The immediate availability of bulk picture and video data at the ground station would be a breakthrough in SAR missions, traditionally carried by hu- mans and dogs. For instance, delivering high-resolution im- ages of the supervised surface to rescuers is a “must-to-have” necessity to spot an injured individual in short time. In this Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage, and that copies bear this notice and the full ci- tation on the first page. Copyrights for third-party components of this work must be honored. For all other uses, contact the owner/author(s). Copyright is held by the author/owner(s). WiNTECH’13, September 30, 2013, Miami, Florida, USA. ACM 978-1-4503-2364-2/13/09. http://dx.doi.org/10.1145/2505469.2506491. Gumstix WiFi Xbee Pro Figure 1: The UAV: Arducopter. contribution, we present our multi-hop UAV networking so- lution to this problem in two representative use cases: es- tablishing end-to-end connectivity to the smartphone of a missing person, and, streaming high-resolution videos of the area of interest. 2. FLYING PLATFORM We employ two “Arducopters” as our UAVs, which are quadrocopters equipped for outdoor flights (see Figure 1). Their firmware is based on Arduino [1]. For each UAV, an electrical motor drives its four propellers and enables flying. A lithium polymer battery is used that provides flight autonomy of up to 20 minutes. We operate the UAVs at the default cruise speed of about 4.5 m/s and at a safe altitude (up to 100 m). The main electronic system of the UAV is the autopilot, which integrates a GPS unit, pressure sensors, and inertial sensors. The autopilot enables the UAV to take off and land autonomously and to navigate through defined way-points. Way-points can be set through a graphical user interface (GUI) on the ground station. We have selected QGround- Control as GUI [5] since it is open source, easy to extend, and well-documented. 3. HYBRID NETWORK In SAR missions, UAV networks should support two dif- ferent types of data: one are light-weight status, sensor data, and commands, and the other are bulk data. On the one hand, commands and status information demand only low throughput but reliable links, and on the other hand, trans- 91