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Sandqvist A.,Albanova University Center | Hjalmarson A.,Chalmers University of Technology | Frisk U.,Omnisys Instruments AB | Lundin S.,OHB Sweden | And 3 more authors.
Astronomy and Astrophysics | Year: 2017

Context. The Odin satellite is now into its sixteenth year of operation, much surpassing its design life of two years. One of the sources which Odin has observed in great detail is the Sgr A complex in the centre of the Milky Way. Aims. To study the presence of NH3 in the Galactic centre and spiral arms. Methods. Recently, Odin has made complementary observations of the 572 GHz NH3 line towards the Sgr A +50 km s-1 cloud and circumnuclear disk (CND). Results. Significant NH3 emission has been observed in both the +50 km s-1 cloud and the CND. Clear NH3 absorption has also been detected in many of the spiral arm features along the line of sight from the Sun to the core of our Galaxy. Conclusions. The very large velocity width (80 km s-1) of the NH3 emission associated with the shock region in the southwestern part of the CND may suggest a formation/desorption scenario similar to that of gas-phase H2O in shocks/outflows. © ESO, 2017.


Bergh M.,Swedish Defence Research Agency | Garcia V.,OHB Sweden
Shock Waves | Year: 2017

Man-made space debris is dominating the background meteorite environment with a growing debris population leading to increased collision risks for satellites, especially in the low Earth orbit and geostationary orbit protected environments. Here we present a computational model for estimating the effect of hypervelocity impact from debris particles on non-shielded propellant and pressurant tanks. Eulerian hydrocode simulation is utilised to model firstly penetration and shock wave formation in the propellant and secondly subsequent detonation wave propagation and interaction with the tank wall. Furthermore, reactive molecular dynamics is used to estimate the risk of detonation in a liquid hydrazine layer. We present simulations of a 3.5 mm aluminium spherical debris particle at a velocity of 14 km/s relative to a hydrazine tank. We find that the degree of damage is strongly dependent on tank temperature and hence on the satellite thermal configuration at its end of life. © 2017 The Author(s)


Rathsman P.,OHB Sweden | Demaire A.,OHB Sweden AB | Rezugina E.,OHB Sweden AB | Lubberstedt H.,OHB System AG | De Tata M.,OHB System AG
Proceedings of the International Astronautical Congress, IAC | Year: 2013

In September 2003, ESA launched the lunar probe SMART-1. Using a single electric thruster providing only 70 mN of thrust, SMART-1 traversed the radiation belts under the worst solar storm conditions ever recorded to successfully reach the Moon in November 2004. Ten years later, the legacy of SMART-1 has been an important contributor to the implementation of the Electra programme, aimed at developing Europe's first all-EP telecommunications satellite. Thanks to the significant mass saving offered by electric propulsion, Electra will be able to host the same payload capability as traditional mid-sized telecom satellites, whilst achieving a much lower launch mass. The paper discusses the challenges associated with the implementation of all-electric propulsion on telecom satellites, and explains how the experiences of SMART-1 and other relevant missions have contributed to Electra. The first Electra mission is planned to be launched in the 2018-2019 timeframe.


D'Amico S.,German Aerospace Center | Ardaens J.-S.,German Aerospace Center | Larsson R.,OHB Sweden | Larsson R.,German Space Operations Center
Journal of Guidance, Control, and Dynamics | Year: 2012

The Prototype Research Instruments and Space Mission Technology Advancement (PRISMA) represents the first European technology demonstration of formation-flying and on-orbit-servicing techniques. Several hardware and software experiments, either at subsystem or system levels, have been successfully conducted since the launch of the dual-satellite mission in June 2010. This paper describes the guidance, navigation, and control functionalities and presents key flight results from the so-called Spaceborne Autonomous Formation-Flying Experiment (SAFE) executed in September 2010 and March 2011 as one of the primary PRISMA mission objectives. SAFE is intended to demonstrate autonomous acquisition, keeping, and reconfiguration of passive relative orbits for advanced remotesensing and rendezvous applications. As shown in the paper, the onboard Global Positioning System navigation system provides relative orbit information in real time with an accuracy better than 10 cm and 1 mm=s (threedimensional, root mean square) in position and velocity, respectively. The impulsive formation control achieves accuracies better than 10m(three-dimensional, root mean square) for separations below 2 km with minimum usage of thrusters, ensuring high predictability for simplified mission operations and minimum collision risk for increased safety. © 2011 by Simone D'Amico, Jean-Sebastien Ardaens, and Robin Larsson.


Karlsson T.,OHB Sweden | Larsson R.,OHB Sweden | Jakobsson B.,OHB Sweden | Bodin P.,OHB Sweden
Advances in the Astronautical Sciences | Year: 2014

PRISMA was launched on June 15, 2010 to demonstrate strategies and technologies for formation flying and rendezvous. OHB Sweden is the prime contractor for the project which is funded by the Swedish National Space Board with additional support from DLR, CNES, and DTU. In April 2013, when both the nominal and extended mission phases were successfully completed, new objectives were assigned to the Mango spacecraft and the Tango spacecraft was shut down permanently. An eighteen month journey was started towards a new, non-cooperative space object to demonstrate rendezvous and inspection within an experiment called IRIDES (Iterative Reduction of Inspection Distance with Embedded Safety). Since the start of IRIDES, the Mango spacecraft has completed a series of optimized orbit maneuvers, involving semi-major, inclination and eccentricity changes that have put the spacecraft on a drift towards the new object. The rendezvous is expected in the second half of 2014 and will demonstrate optical relative navigation technologies and the characterization of the rendezvous object and its motion with the use of the on-board video system. The inspection strategy within IRIDES includes a series of inherently collision free drift maneuvers through the cross-track/radial plane of the rendezvous object, and a successively reduction of the closest relative distance.


Bodin P.,OHB Sweden | Nylund M.,Swedish Defence Research Agency | Battelino M.,OHB Sweden
Acta Astronautica | Year: 2012

The satellite simulator SATSIM was developed during the experimental PRISMA multi-satellite formation flying project and was primarily aimed to validate the Guidance, Navigation and Control system (GNC) and the on-board software in a simulated real-time environment. The SATSIM system has as a main feature the ability to simulate sensors and actuators, spacecraft dynamics, intra-satellite communication protocols, environmental disturbances, solar illumination conditions as well as solar and lunar blinding. The core of the simulator consists of MATLAB/Simulink models of the spacecraft hardware and the space environment. The models run on a standard personal computer that in the simplest scenario may be connected to satellite controller boards through a CAN (Controller Area Network) data bus. SATSIM is, in conjunction with the RAMSES Test and Verification system, able to perform open-loop, hardware-in-the-loop as well as full-fledged closed-loop tests through the utilisation of peripheral sensor unit simulators. The PRISMA satellites were launched in June 2010 and the project is presently in its operational phase. This paper describes how a low cost but yet reliable simulator such as the SATSIM platform in different configurations has been used through the different phases of a multi-satellite project, from early test of onboard software running on satellite controller boards in a lab environment, to full-fledged closed-loop tests of satellite flight models. © 2011 Elsevier Ltd. All rights reserved.


Gohardani A.S.,Springs of Dreams Corporation | Stanojev J.,OHB Sweden | Demaire A.,OHB Sweden | Anflo K.,ECAPS | And 3 more authors.
Progress in Aerospace Sciences | Year: 2014

Currently, toxic and carcinogenic hydrazine propellants are commonly used in spacecraft propulsion. These propellants impose distinctive environmental challenges and consequential hazardous conditions. With an increasing level of future space activities and applications, the significance of greener space propulsion becomes even more pronounced. In this article, a selected number of promising green space propellants are reviewed and investigated for various space missions. In-depth system studies in relation to the aforementioned propulsion architectures further unveil possible approaches for advanced green propulsion systems of the future. © 2014 Elsevier Ltd.


Vinterhav E.,OHB Sweden | Genberg M.,Luna Resort | Von Scheele F.,Omnisys
62nd International Astronautical Congress 2011, IAC 2011 | Year: 2011

The House on the Moon could be the first deep space art installation ever. The project is an endeavour to put a traditional red Swedish house with white corners on the surface on the lunar surface as a cultural symbol. The project is set up as a public private partnership where private interests participate for commercial returns and public organisation participate for scientific returns. In the process of moving the project forward a feasibility study of a national Swedish lunar lander mission was prepared that indicated that placing 30kg payload on the lunar surface could be achieved at a cost of less than 100 million Euros. Technical studies on the house indicate that it is possible to design a 10kg and 6-litre payload that will deploy autonomously into a house with the dimensions of 2,5 x 3.0m x 2.0m. The House payload is estimated to fit inside a cost of 3 million Euros. Finding a way to finance the House on the Moon is a challenge and the funding model for the mission is a combination of inviting external partners to pay for sharing the additional 20 kg payload capacity and sponsorship. The paper outlines the House on the Moon project, its artistic concept, commercial models and technical models and its progress to date. Copyright ©2010 by the International Astronautical Federation. All rights reserved.


Lundin S.,OHB Sweden | Silverlind S.-O.,OHB Sweden | Vinterhav E.,OHB Sweden
62nd International Astronautical Congress 2011, IAC 2011 | Year: 2011

The mission Odin remains a Swedish-led, scientific, 3-axis stabilised, fine-pointing, small satellite with two payloads that provides high quality spectroscopy data in the optical, mm and submm regions. End-users are atmosphere and astronomy scientists in Canada, France, Finland and Sweden. The satellite may with favour be regarded as the second stage in a three-stage rocket of increasingly precise astronomy research in the submm wavelength band. It started with NASA's Submillimeter Wavelength Astronomy Satellite, SWAS (1998-2005), continued with Odin (2001-) and ends with ESA's Herschel satellite launched in 2009. After 10 years in orbit, me main interest is in the atmosphere science mission and the satellite is now in a continuous atmosphere observation mode interrupted only for calibrations and observations of occasional comets and otfier irregularly occurring astronomical objects. Routines have settled and the behaviour of the spacecraft is well known. Operations are now performed by a minimum of staff validating, monitoring and commanding the satellite. After more than 55000 orbit revolutions, over 10 years in space, Odin has outperformed its design lifetime with a factor of five. Scientists are now hoping that Odin will collect atmospheric data continuously over a full solar cycle. After ten years Odin has to be operated more carefully but this has little impact on the quality of scientific data. Occasional hiccups occur but these are efficiently analysed and problems are resolved by a team of engineers that can be called in on short notice. The paper summarizes Odin's 10 years in space with highlights of important milestones.


News Article | February 22, 2017
Site: phys.org

Even the most complex of systems comes down to properly configured wires and cables, such as those pictured here on the Propulsion Qualification Model of the Orion service module. ESA's contribution to NASA's Orion spacecraft is the European Service Module, designed to provide the spacecraft's propulsion, electrical power, water and thermal control. The model, designed by Airbus Defence and Space, was assembled by OHB Sweden. Made from steel and containing propellant and helium tanks, among various electronics and command systems, the Propulsion Qualification Model allows engineers to determine how well systems are working together. The model was built in January in Stockholm, Sweden and has since been shipped to the White Sands Test Facility in New Mexico (USA), where it will undergo more extensive testing by NASA, ESA and main contractor Airbus DS. Explore further: European space agency to help NASA take humans beyond moon

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