Under the catchphrase 'Knowledge for Tomorrow', the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) is presenting its technological innovations in aerospace at the Paris Air Show. The 51st Air Show in Paris, one of the largest and most important aerospace exhibitions in the world, provides an exciting platform for leading representatives of the industry. From 15 to 21 June, 2015, the latest developments in aerospace will be on show at Le Bourget airport. In Hall 2C, in the German Pavilion, DLR will showcase 17 exhibits. In the outdoor area, DLR will display the largest member of its research fleet, the Airbus A320 Advanced Technology Research Aircraft, D-ATRA.
Early detection of forest fires
Forest fires are a danger for both humans and nature; they contribute to air pollution and can harm the economy. However, if they are they discovered early enough, the risks can be reduced and the damage minimised. The Bi-spectral Infrared Optical System (BIROS), a mini-satellite developed at the DLR Institute of Optical Sensor Systems should, as part of the FIREBIRD mission and in conjunction with the TET-1 satellites, be able to detect forest fires early.
Early detection of forest fires
The two Earth observation satellites TerraSAR-X and
The objective of the TanDEM-X mission (TerraSAR-X add-on for Digital Elevation Measurement) is to produce a highly accurate, three-dimensional image of our Earth with uniform quality and unprecedented accuracy. For large parts of the earth, only rough, non-uniform or incomplete elevation models from different data sources and survey methods existed before the mission began. The previous maps therefore often have breaks, for example at national borders, or they are difficult to compare because they were created with different measurement methods and time-staggered measurement campaigns. TanDEM-X closes these gaps and provides a homogeneous elevation model as an indispensable basis for many commercial applications and scientific questions.
For this purpose, two almost identical satellites orbit the earth at an altitude of around 500 kilometres and scan the surface with radar equipment. The first of the two satellites, TerraSAR-X, has been operating successfully in space since 2007. Since 2010, it has been followed by the almost identical satellite TanDEM-X. Both fly only a few hundred metres apart in close formation, thus enabling the simultaneous imaging of the terrain from different angles. From this, precise elevation information is derived in a 12-metre grid and with a vertical accuracy of better than two metres.
The TanDEM-X Mission
TanDEM-X and TerraSAR-X form the first configurable SAR interferometer (SAR = Synthetic Aperture Radar) in space. The TanDEM-X satellite is a replica of TerraSAR-X with minor extensions. It has an additional cold gas propulsion system and can therefore fine-tune its orbit for formation flight with TerraSAR-X. TanDEM-X also receives attitude and position data from its twin satellite. Since SAR systems actively "illuminate" the earth's surface with its radar signals, measurements can be carried out around the clock, independent of daylight. In addition, SAR systems are largely independent of weather conditions, as the radar signals are able to penetrate clouds. Compared to optical sensors, images of the earth's surface can therefore be taken at any time. This contributes significantly to the reliability of the entire system, a feature that is increasingly demanded by many users.
In the period from 2011 to 2015, both satellites have surveyed the entire land surface of the Earth, i.e. 150 million square kilometres, several times completely in order to ensure the main objective of the mission, the creation of the global Digital Elevation Model (DEM). The global TanDEM-X terrain model has a grid size of 12 meters × 12 meters and has a high vertical accuracy, which is mostly better than 2 meters. Furthermore, it is homogeneous throughout and thus forms the basis for a globally uniform map material.
The production of the global terrain model from the acquired data set of both satellites was completed in September 2016. About 3 petabytes (equivalent to 3000 terabytes) of data were processed into the final digital 3D map product, which is now available in the form of 19,000 tiles. Each tile represents an area of 1° × 1° (longitude × latitude), corresponding to about 100 km × 100 km near the equator. The global TanDEM-X terrain model is also available in different product variants with a grid size of 12 m, 30 m and 90 m.
The three-year acquisition phase for the global elevation model was followed by an acquisition phase to explicitly serve scientific needs such as forest mapping, snow and ice detection, observation of volcanoes, urban areas, ocean currents and the demonstration of new radar techniques to develop new applications.
If the earth's surface is analysed with the accuracy of TanDEM-X, it can be clearly seen that this is an extremely dynamic system. Not only altitude changes in glaciers, permafrost areas and forests, but also agricultural activities and changes in infrastructure leave clear traces in the digital terrain model. Therefore, since September 2017 a further complete survey of the Earth's landmass has been carried out in order to obtain another independent and unique data set. The resulting product, called "Change DEM", will make it possible to track topographic changes worldwide.
A German key project
Following in the footsteps of European radar satellites ERS-1, ERS-2, Envisat and TerraSAR-X, as well as the joint US-German-Italian Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew on the Space Shuttle and the US Shuttle Radar Topography Mission, TanDEM-X seeks to support scientific and commercial applications of radar-based Earth observation. Demonstrating Germany's expertise in satellite-based radar technology, the mission is the result of a long-term focus in Germany's national space programme.
TanDEM-X was launched on behalf of DLR as a public-private partnership (PPP) project with Airbus Defence and Space (formerly Astrium) with funding from the German Federal Ministry of Economics and Energy (BMWi).
DLR is responsible for the scientific use of the TanDEM-X data, the planning and execution of the mission, the control of the two satellites and the generation of the digital elevation model.
Airbus Defence and Space built the satellite and contributes to the development and utilisation costs. As with TerraSAR-X, the "Geo-Intelligence" programme line is responsible for the commercial marketing of the TanDEM-X data. Since 2016, the project has been continued under a continuation agreement with Airbus.
|TanDEM-X quick facts|
|Launch:||21 June 2010, 04:14:03 CEST|
|Launch site:||Baikonur (Kazakhstan)|
|Orbit altitude:||514 kilometres|
|Orbit inclination:||97.4 degrees|
|Satellite mass:||1330 kilograms|
|Satellite dimensions:||Height: 5 metres|
Diameter: 2.4 metres
|Power consumption:||730 watts (average)|
|Mission operation:||German Space Operations Center, Oberpfaffenhofen|
|Satellite command:||Weilheim ground station|
|Data reception:||Ground stations:|
- Inuvik, Canada
- O'Higgins, Antarctic
- Kiruna, Sweden
|Satellite lifetime:||5.5 years (6.5 years for consumables)|
|Radar centre frequency:||9.65 gigahertz (X-band)|
The mission involves the DLR Microwaves and Radar Institute, the DLR Remote Sensing Technology Institute and the DLR German Remote Sensing Data Centre, who jointly form the "SAR Centre of Excellence". The institutes complement each other by covering all relevant fields from sensor technology and mission design to high-precision operational processing and value-added end-user products. Together with DLR's German Space Operations Centre, they are also responsible for setting up the ground segment respectively the infrastructure for operating the satellites and processing the data. The DLR Microwaves and Radar Institute in Oberpfaffenhofen is responsible for scientific coordination.
DLR presents a mission concept
Tandem-L is a satellite mission for the global observation of dynamic processes on Earth’s surface. At a never previously achieved quality and resolution, the two satellites will cover a 350-kilometre wide swathe while flying in formation – regardless of the time of day and the weather. DLR is presenting the mission concept at the show stand.
Quick overview in the event of disaster
When a natural disaster occurs, geographical images and accurate altitude information on the affected area are very important for providing rapid assistance and making an assessment of the damage. With the Modular Aerial Camera System (MACS-Himalaya project homepage), developed and built by DLR, this is now possible. Detailed, colour 3D models can be computed from the MACS images. In January 2014 for example, images were acquired of Pokhara, Kathmandu and the Mount Everest region of Nepal; after the devastating earthquake in April 2015 these were sent to aid workers at the scene.
New test stand for European Ariane launcher
In September 2014, DLR and ESA laid the foundation stone for the new P5.2 upper stage test stand at the DLR Lampoldshausen site. Here, future upper stages of the new Ariane-6 launcher will be tested. These include tests for assessing refuelling and defueling as well as hot running tests of the stage with the Vinci engine. With this new facility at DLR in Lampoldshausen, complete cryogenic upper stages can be qualified as well as engines and components – a new possibility for Europe – demonstrating the leading position of DLR in this area. At the same time, DLR is making a decisive contribution to the development of the Ariane program and is contributing to the preservation of autonomous access to space for Europe. The commissioning of the unique European P5.2 test stand will take place in 2018.
Around the world at 20 times the speed of sound
Travel from Europe to Australia in 90 minutes – the DLR SpaceLiner concept will make exactly that possible. Similar to a Space Shuttle, the SpaceLiner, developed at the DLR Institute of Space Systems will use its rocket engines to take off vertically. The reusable booster stage then separates from the orbiter and the passenger capsule, which seats 50 people, begins its glide at 20 times the speed of sound after eight minutes.
The Rosetta mission is designed to investigate the origins of the Solar System. For this purpose, one of the oldest bodies in the Solar System was chosen – a comet from the Kuiper belt named 67P/Churyumov-Gerasimenko. ESA's Rosetta spacecraft has been orbiting the 4.5-million-year-old comet since May 2014. On 12 November 2014, the Philae spacecraft landed on the comet. The lander is a joint project of DLR, the Max Planck Institute for Solar System Research, the French Space Agency, CNES and the Italian Space Agency (ASI). All ten instruments installed on Philae were used in its first 64 hours on the comet's surface. After that, the lander transitioned into a dormant phase because the power from its batteries were exhausted.
As part of the Helmholtz Robotic Exploration of Extreme Environments (ROBEX) project, together with its partners the DLR Robotics and Mechatronics Center is developing a Docking Interface System. The involved institutions are collaborating on technologies that will enable extreme environments such as the ocean depths and Earth's moon to be explored. The semi-automatic docking system is able to transmit power and data between a robot arm and scientific instruments and is more secure, reliable and robust.
Always in touch
Since May 2013, the ESA PROBA-V satellite has been orbiting Earth with an Automatic Dependence Surveillance Broadcast (ADS-B) signal receiver on board. These signals are transmitted from the aircraft and contain information on their position, speed and identity. However, ground stations can only cover certain areas, for example, an aircraft over the Atlantic is not covered. This gap will now be closed with the aid of monitoring from space.
Fuel research for aircraft
Together with NASA and the Canadian National Research Council, DLR scientists are working towards answering the question of how carbon dioxide emissions from aviation can be reduced. The purpose of the ACCESS-II project (Alternative Fuel Effects on Contrails and Cruise Emissions) in 2014 was to measure the emissions of a biofuel-kerosene mixture at a typical cruising altitude of 100 metres to 20 kilometres. In future, as part of ECLIF (Emission and Climate Impact of Alternative Fuels), DLR will continue to research alternative fuels.
Combustion chamber optimisation
On their test stand, researchers at the DLR Institute of Combustion Technology can look into the innermost part of engines – the combustion chamber. These observations and analyses provide important basic knowledge, enabling innovative gas turbines to be developed. Amongst other things, how flames behave in different air-fuel mixtures is being explored. In this way, the efficiency can be increased and emissions reduced.
The Optimode project will be tested using the example of 'airport transfer hubs'. How do passengers get to the airport? What happens if a train with 80 passengers is delayed? In the control centre, all relevant planned and actual times and dates of flights, as well as movements by transportation providers and travellers are collected and merged. The aim of the project is to be able to make adjustments depending on the situation - such as opening more security checks, changing the departure time or rerouting passengers to their gate.
Improved wing leading edges
At the DLR Institute of Composite Structures and Adaptive Systems, researchers have merged design contradictions with one another; the 'droop nose' is a smooth, flexible leading edge that combines flexibility with rigidity. The aim of this development is to reduce drag, fuel consumption and noise emission caused by the airframe.
A different way of flying
A FanWing is characterised by a cylindrical rotor cage along the leading edge of the wing, which rotates to generate propulsion and lift. A FanWing aircraft is not equipped with the standard engines beneath the wing or on the fuselage. Instead, the blades of the rotor cage causes the air required for propulsion to flow directly across the wings, enabling the FanWing to operate from extremely short runways.
DLR ATRA research aircraft
In the static display at the Paris Air Show, DLR is exhibiting its A320 Airbus, D-ATRA (Advanced Technology Research Aircraft). It is the largest member of the DLR fleet and has been in service since 2008. Numerous modifications had to be made to the aircraft for its use as a research and test aircraft. The focus lies on, amongst other things, tests of aeroelastic measurement procedures, research into interior acoustics, measurements of flow noise, new comfort and safety features, as well as the measurement of vortex drag. ATRA is a unique research platform in the field of aerodynamics, avionics and propulsion technology.
Is it also quieter?
Slower landing also means quieter landing. How much slower, steeper and quieter a modern airliner can fly to its destination airport is being tested by DLR researchers in the High lift Inflight Validation (HINVA) project. For this purpose, observing how the airflow behaves over the wings, high-lift devices and engine nacelles is crucial. This has now be measured with unprecedented accuracy and detail. The results are important for new concepts of aviation and benefit the entire aviation industry. The measurement probes are still mounted on the wings of ATRA and the instrumentation racks on the aircraft can be viewed.