SEARCHING LOST PEOPLE WITH UAVS: THE SYSTEM AND RESULTS OF THE CLOSE-SEARCH PROJECT

This paper will introduce the goals, concept and results of the project named CLOSE-SEARCH, which stands for ’Accurate and safe EGNOS-SoL Navigation for UAV-based low-cost Search-And-Rescue (SAR) operations’. The main goal is to integrate a medium-size, helicopter-type Unmanned Aerial Vehicle (UAV), a thermal imaging sensor and an EGNOS-based multi-sensor navigation system, including an Autonomous Integrity Monitoring (AIM) capability, to support search operations in difficult-to-access areas and/or night operations. The focus of the paper is three-fold. Firstly, the operational and technical challenges of the proposed approach are discussed, such as ultra-safe multi-sensor navigation system, the use of combined thermal and optical vision (infrared plus visible) for person recognition and Beyond-Line-Of-Sight communications among others. Secondly, the implementation of the integrity concept for UAV platforms is discussed herein through the AIM approach. Based on the potential of the geodetic quality analysis and on the use of the European EGNOS system as a navigation performance starting point, AIM approaches integrity from the precision standpoint; that is, the derivation of Horizontal and Vertical Protection Levels (HPLs, VPLs) from a realistic precision estimation of the position parameters is performed and compared to predefined Alert Limits (ALs). Finally, some results from the project test campaigns are described to report on particular project achievements. Together with actual Search-and-Rescue teams, the system was operated in realistic, user-chosen test scenarios. In this context, and specially focusing on the EGNOS-based UAV navigation, the AIM capability and also the RGB/thermal imaging subsystem, a summary of the 1 INTRODUCTION The use of Unmanned Aerial Vehicles (UAVs) —more in gen- eral, Unmanned Aerial Systems (UASs)— for SAR operations is not new and has been traditionally fed by developments made in other fields. The main driver of UAV technology has been (and still is) the military field and this is because the nature of military developments is fairly overlapping SAR needs. As a example of that, we recall the UAVs used in the Iraq and Afghanistan wars were deployed to find people trapped in New Orleans buildings devastated by Hurricane Katrinas flood waters. Those platforms were equipped with thermal imaging systems to detect the body heat of storm survivors. A second example was the use of rotary- wing UAV platforms providing on-site imagery from the nuclear incident in Fukushima. More recently, a field that is increasingly putting effort on UAV development is Geomatics: the potential of those light-weight, easy-deployable platforms to quickly provide aerial and/or ground, good quality imagery is huge. A clear ex- ample of this interest raised within the geomatic community is the recent acquisition of Gateway, a provider of lightweight UAVs for photogrammetry and rapid terrain mapping applications, by Trimble. Indeed, the multi-application of the UAV potential to other fields, such as SAR, shall not be neglected. And even if [the lack of] regulations have been the stopper of the final jump to commercial applications, the willingness of regulators seems finally positive on pulling the trigger. As stated in the Institute of Navigation newsletter in winter 2011, ”the United States trans- portation secretary must develop a comprehensive plan to safely accelerate the integration of civil UAS into the national airspace system as soon as practicable, but not later than September 30th, 2015.” results is presented

Geometric Calibration and Radiometric Correction of LiDAR Data and Their Impact on the Quality of Derived Products

LiDAR (Light Detection And Ranging) systems are capable of providing 3D positional and spectral information (in the utilized spectrum range) of the mapped surface. Due to systematic errors in the system parameters and measurements, LiDAR systems require geometric calibration and radiometric correction of the intensity data in order to maximize the benefit from the collected positional and spectral information. This paper presents a practical approach for the geometric calibration of LiDAR systems and radiometric correction of collected intensity data while investigating their impact on the quality of the derived products. The proposed approach includes the use of a quasi-rigorous geometric calibration and the radar equation for the radiometric correction of intensity data. The proposed quasi-rigorous calibration procedure requires time-tagged point cloud and trajectory position data, which are available to most of the data users. The paper presents a methodology for evaluating the impact of the geometric calibration on the relative and absolute accuracy of the LiDAR point cloud. Furthermore, the impact of the geometric calibration and radiometric correction on land cover classification accuracy is investigated. The feasibility of the proposed methods and their impact on the derived products are demonstrated through experimental results using real data

Precision measurement of the speed of propagation of neutrinos using the MINOS detectors

We report a two-detector measurement of the propagation speed of neutrinos over a baseline of 734 km. The measurement was made with the NuMI beam at Fermilab between the near and far MINOS detectors. The fractional difference between the neutrino speed and the speed of light is determined to be (v/c-1) = (1.0±1.1) × 10^−6, consistent with relativistic neutrinos

First record of the rare freshwater alga Tetrasporopsis fuscescens (Chrysomerophyceae, Ochrophyta) in North America

Multiple alignments of the nuclear SSU rDNA and plastid rbcL, psaA, psbA and psbC loci sequences built either manually in MEGA6 or using MAFFT v6, applying the Q-INS-i strategy

Comparing morphological and molecular estimates of species diversity in the freshwater genus Synura (Stramenopiles): a model for understanding diversity of eukaryotic microorganisms.

Multiple alignments of the nuclear ITS rDNA, SSU rDNA and LSU rDNA, plastid rbcL, psaA and LSU rDNA, and mitochondrial coxI loci sequences built either manually in MEGA6 or using MAFFT v6, applying the Q-INS-i strategy. In more variable loci alignments, those positions included in subsequent evolutionary analyses are indicated by mask

Diversity of Eukaryotic microorganisms: Comparing morphological and molecular estimates in a freshwater genus Synura (Stramenopiles)

Multiple alignments of the nuclear ITS rDNA, SSU rDNA and LSU rDNA, plastid rbcL, psaA and LSU rDNA, and mitochondrial coxI loci sequences built either manually in MEGA6 or using MAFFT v6, applying the Q-INS-i strategy. In more variable loci alignments, those positions included in subsequent evolutionary analyses are indicated by mask

Speciation in protists: Spatial and ecological divergence processes cause rapid species diversification in a freshwater chrysophyte: Supplementary datasets

Multiple alignments of the ITS rDNA, psaA, coxI, rbcL and SSU rDNA loci sequences built either manually in MEGA6 or using MAFFT v6, applying the Q-INS-i strategy. Positions included in subsequent evolutionary analyses are indicated by mask

Photobiont-mediated guilds in green algal lichens – an insight into the life of terrestrial symbiotic communities

Multiple alignment of the ITS rDNA locus sequences built using MAFFT v6, applying the Q-INS-i strategy, and improved by eliminating the ambiguously aligned regions using Gblocks v. 0.91b. Positions included in subsequent evolutionary analyses are indicated by mask