Infrared Remote-Sensing and Results of the DLR FireBIRD Mission

Forest- and vegetation fires have become more and more out of control worldwide resulting in a devastating impact on the world’s environment. Beside the detection of the fire hotspot itself it is important to evaluate different parameters to support the work of the firefighters (e.g. mean fire temperature, length-of-fire front, cluster size and fire location). On the other hand fires around the world have a major impact on the atmosphere and influence the climate. This influence can be calculated by the fire-radiative -power (FRP) which measures the radiant energy released per time unit by the fires. The German Aerospace Center (DLR) is making a major contribution to fire detection with the FireBIRD constellation. This constellation consists of the two satellites TET-1 (Technology Experiment Carrier) built by industry, launched in 2012 and BIROS (Bi-spectral Infrared Optical System) built by DLR in Berlin and launched in 2016. A new compact bi-spectral infrared system was developed for both satellites capable to detect and evaluate smaller fires and hot spots compared to other infrared remote-sensing systems (e.g. Modis sensor, Sentinel-3). The BIROS satellite is also carrying different new technological experiments for the in-orbit demonstration of features for the next generation of remote sensing satellites. The BIROS primary mission objectives are: - Test of a two-satellite-constellation together with TET for infrared remote sensing of high-temperature events (HTE) on Earth surface - Active fire detection and monitoring and analysis of results The secondary mission objectives consist of: - Development and test of new high-torque-wheels (HTW) for high agility - Development and test of a small cold-gas propulsion system for station keeping and proximity operations - Formation flying with BEESAT-4 satellite from TU-Berlin (separation from BIROS) with InterSatellite-Link - Experiments of space debris analysis in using laser reflectors - Real-time information generation (on-board) and extraction of fire attributes with distribution to the user via an Orbcomm modem The main payload is a multi-sensor system designed to fulfill the scientific requirements under the conditions of a micro satellite. The sensor system consists of the following main components: an infrared sensor system based on cooled CdHgTe detectors in the medium infrared (3.4-4.2µm), a thermal infrared channel (8.5-9.3µm) and 3-line CCD-pushbroom camera with green-, red- and near/infrared -channel. The BIROS satellite bus was funded as a DLR external-project by the German Ministry of Education and Research (No. 01LK0904A). All other mission segments are covered by DLR. The scientific mission results will be demonstrated by different examples of fire products and applications taken around the world. The in-orbit results for the technological experiments will show on one hand the potential for new space components as “smart devices”. On the other hand these new technologies and methods on board BIROS will initiate new applications and research topics for the next generation of small satellites: for e.g. remote sensing, on-board autonomy, formation-flying or space-robotics

High Torque Wheels for agile Satellite Maneuvers - in Orbit Experiences and future Steps with Recuperation of Energy

Agility is a necessary skill for several tasks. This applies in particular to remote sensing applications, but is also useful for optical communication from satellite to ground. While discussing a new reconnaissance satellite, the need for suitable actuators for agile maneuvers was identified several years ago. Developments for robotics at DLR (e.g. ROKVIS experiment on board the ISS (2004-2011) resulted in the possibility to further develop the reaction wheel principle for the special application "high torque" for fast accelerations. This was in competition with the widespread use of control momentum gyros (CMG). It was decided to equip the small satellite BIROS (launch 2016) with three “High Torque Wheels” (HTW) as additional technological payload. With this down-scaled version of the HTWs, the proof of the concept should be made under real conditions in space. This included various agile satellite maneuvers such as for “in track stereo”, scanning up to 5 parallel image strips on ground or switching between different targets on ground. This of course required changes to the ACS and the power supply system, which was a reuse of technology from the DLR small satellite TET-1. The attitude control system (ACS) uses several “attitude modes” for a comfortable and autonomous attitude control of the satellites in space. This was extended by a special “Fast Slew Mode”, which was developed for fast maneuvers using HTWs. The standard satellite slew rate is 0.5 degrees per second with a freely selectable single slew axis. A fast slewing maneuver intends to reorient the satellite by up to 30 degrees within 10 seconds. Actually however, the satellite achieved angular speeds of up to 10 degrees per second in space. A fast slew maneuver is finished, when all the HTWs are nearly stopped and the default ACS actuators took over the remaining angular momentum. This process of momentum exchange between the actuator systems was one important aspect of investigations. Another test case was the usage of these 3 experimental HTWs as actuator of the ACS. After successful completion of the first experimental phase in orbit the work will be continued by improving the fast slew maneuver algorithms and by preparing a second experimental phase in space including active payload cameras in the defined image scenarios. The HTW will be equipped now with an energy recuperation system storing electrical energy instead of kinetic energy within a spinning CMG

Projekt-Abschlussbericht DLR-FB-2019-33 DLR-FuE-Projekt Peak Power Platform Programm: GigaStore

Die Aufgabenstellung des Projektes Peak Power Platform war für eine konkrete Anwendung, ne-ben Grundlagenbetrachtungen zur Technologie, einen sogenannten strukturintegrierten Energie-speicher mit einem speziellen elektrischen Energieeinspeisungs- und -rückspeisesystem zu definieren und als Demonstrator aufzubauen. Dabei soll die Technologie durch eine Weltraum-Qualifizierung und elektrochemische Charakterisierung überprüft und als System modelliert bzw. nach den folgenden Parametern bewertet werden: Optimiertes Leistung/Gewichts-Verhältnis ( Leistungsdichte ) Qualifikation des Systems (Radiation, Thermal, Vibration, Pyro-Shock, EMV) Hohe Zyklen-Festigkeit, Langzeitstabilität ( Degradation ) Integrationsfähigkeit in Satellitenstrukturen Kaskadierbarkeit in Kondensatorbänken mit hoher Zuverlässigkeit der Zellen Hybridisierbarkeit mit Standard-Batteriesystemen kurzfristig (innerhalb 3 Jahren) Erreichung eines anwendbaren Technologielevels (TRL5

High Torque Wheels for agile Satellite Maneuvers - in Orbit Experiences and future Steps with Recuperation of Energy

Agility is a necessary skill for several tasks. This applies in particular to remote sensing applications, but is also useful for optical communication from satellite to ground. While discussing a new reconnaissance satellite, the need for suitable actuators for agile maneuvers was identified several years ago. Developments for robotics at DLR (e.g. ROKVIS experiment on board the ISS (2004-2011) resulted in the possibility to further develop the reaction wheel principle for the special application "high torque" for fast accelerations. This was in competition with the widespread use of control momentum gyros (CMG). It was decided to equip the small satellite BIROS (launch 2016) with three “High Torque Wheels” (HTW) as additional technological payload. With this down-scaled version of the HTWs, the proof of the concept should be made under real conditions in space. This included various agile satellite maneuvers such as for “in track stereo”, scanning up to 5 parallel image strips on ground or switching between different targets on ground. This of course required changes to the ACS and the power supply system, which was a reuse of technology from the DLR small satellite TET-1. The attitude control system (ACS) uses several “attitude modes” for a comfortable and autonomous attitude control of the satellites in space. This was extended by a special “Fast Slew Mode”, which was developed for fast maneuvers using HTWs. The standard satellite slew rate is 0.5 degrees per second with a freely selectable single slew axis. A fast slewing maneuver intends to reorient the satellite by up to 30 degrees within 10 seconds. Actually however, the satellite achieved angular speeds of up to 10 degrees per second in space. A fast slew maneuver is finished, when all the HTWs are nearly stopped and the default ACS actuators took over the remaining angular momentum. This process of momentum exchange between the actuator systems was one important aspect of investigations. Another test case was the usage of these 3 experimental HTWs as actuator of the ACS. After successful completion of the first experimental phase in orbit the work will be continued by improving the fast slew maneuver algorithms and by preparing a second experimental phase in space including active payload cameras in the defined image scenarios. The HTW will be equipped now with an energy recuperation system storing electrical energy instead of kinetic energy within a spinning CMG

Valorisation des races anciennes de poulets : facteurs sociaux, technico-économiques, génétiques et règlementaires.

National audienc

Les services écosystémiques dans les espaces agricoles. Paroles de chercheur(e)s

International audienceÉvaluer la biodiversité et les services écosystémiques : pourquoi, comment, pour quels résultats, avec quelles limites ? Jean-Pierre Amigues (Inra-UMR TSE-Lerna) Gérer les services écosystémiques : le cas de l'eau et des milieux aquatiques David A. Bohan (Inra-UMR Agroécologie) Networking Agro-Ecology-reconciling the different needs for ecological functions provided by biodiversity Pascal Carrère (Inra-UREP) Valoriser la diversité des services rendus par la prairie : une voie pour assurer la durabilité des systèmes d'élevage herbagers ? Philippe Lemanceau (Inra-UMR Agroécologie) La biodiversité des sols : un fantastique patrimoine à préserver et valoriser par les services écosystémiques Mickaël Henry (Inra-UR Abeilles et Environnement) Promouvoir la pollinisation entomophile : une vision à large échelle Marc Deconchat, Aude Vialatte, Antoine Brin, David Sheeren (Inra-UMR Dynafor) Concepts et méthodes de l'écologie des paysages pour aider à mieux gérer les services écosystémique

In-Orbit Verification of an Optical Frequency Reference on the ISS Bartolomeo Platform

Within the DLR project COMPASSO, optical clock and link technologies will be evaluated in space on the Bartolomeo platform attached to the Columbus module of the ISS. The system utilizes two iodine-based frequency references, a frequency comb, an optical laser communication and ranging terminal and a GNSS disciplined microwave reference. While COMPASSO is specifically dedicated to test optical technologies relevant for future satellite navigation (i.e. Galileo), the technologies are also crucial for future missions related to Earth observation and science. The optical frequency reference is based on modulation transfer spectroscopy (MTS) of molecular iodine near a wavelength of 532 nm. An extended cavity diode laser (ECDL) at a wavelength of 1064 nm is used as light source, together with fiberoptical components for beam preparation and manipulation. The laser light is frequency-doubled and sent to a mechanically and thermally highly stable free-beam spectroscopy board which includes a 20 cm long iodine cell in four-pass configuration. The iodine reference development is lead by the DLR-Institute of Quantum Technologies and includes further DLR institutes, space industry and research institutions. Phase B of the project will be finalized soon and an Engineering Model of the iodine reference, which represents the flight models in form, fit and function, will be realized by mid 2023. The launch of the COMPASSO payload is planned for 2025

Der Kleinsatellit BIROS in der FireBIRD Mission

Dieser Bericht enthält eine detaillierte Abhandlung des gesamten Entwicklungsprozesses des Bi-spektralen Infrarot-Optischen Systems (BIROS) in der FireBIRD Mission, beginnend mit der wissenschaftlichen Aufgabenstellung zur Detektion und Bewertung von Hochtemperaturereignissen (HTE) aus dem Weltraum über die Auslegung des IR-Kamerasystems als primäre Nutzlast von BIROS, seiner Sekundärnutzlasten, des BIROS Satellitenbusses, dem Nutzerinterface zur Datenanforderung bis hin zu ausgewählten Anwendungsbeispielen der FireBIRD Datenprodukte. Es wird neben der technischen Beschreibung der Subsysteme des Satelliten und der bi-spektralen IR-Kamera, mit Bändern im mittleren Infrarot (MIR) und im thermalenInfrarot (TIR) die adaptive Anpassung der radiometrischen Dynamik der IR-Signaltrakte erklärt. Diese stellt ein Alleinstellungsmerkmal dar im Hinblick auf die bildhafte Erkennung und Bewertung von Feuern oder heißer Lava, welche Temperaturen zwischen 300 °C und 1300 °C erreichen, im sogenannten Sub-Pixelbereich. Anhand von verschiedenen Anwendungsbeispielen wird aufgezeigt, dass mit der IR-Kamera kleine Feuer von nur 10 m2 Ausdehnung zu erkennen sind und gleichzeitig bei der Beobachtung von riesigen Busch-bränden oder groß- flächigen Lavaströmen die IR-Kamera Signaltrakte nicht 'in die Sättigung' gehen, d.h. das Feuersignal nicht begrenzen. Aus der Beobachtung HTE einerseits und von NormalTemperatur-Phänomenen (NTP) konnten die adaptiven Dynamikbereiche für die MIR- und TIRBänder der Kamera nachgwiesen werden, die von keinem anderen IR-Kamaerasystem eines Kleinsatelliten bekannt sind. Die mit BIROS gesammelten Erfahrungen erlauben Schlussfolgerungen für zukünftige Kleinsatellitenmissionen zur räumlich und radiometrisch höher auflösenden Erdbeobachtung im MIR und TIR