This paper reviews solar sail trajectory design and dynamics, attitude control, and structural dynamics. Within the area of orbital dynamics, methods relevant to transfer trajectory design and non-Keplerian orbit generation are discussed. Within the area of attitude control, different control strategies, including utilisation of solar radiation pressure and conventional actuators, are discussed. Finally, the methods of modelling structural dynamics during and after deployment are discussed, before considering possible future trends in developing of solar sailing missions.

Review on solar sail technology

Solar sailing technology challenges

Gossamer-1: Mission concept and technology for a controlled deployment of gossamer spacecraft

Space debris is growing dramatically with the rapid pace of human exploration of space, which seriously threatens the safety of artificial spacecraft in orbit. Therefore, the active debris removal (ADR) is important. This review aims to review the ADR methods and to advance related research in the future. The current research and development status are clearly demonstrated by mapping knowledge domain and charts. In this paper, the latest research results are classified and summarized in detail from two aspects of space debris capture and removal. The scheme comparison and evaluation of all ADR methods are performed, and the applicable scopes of various methods are summarized. Each ADR method is scored using a cobweb evaluation model based on six indicators. Future development of ADR is discussed to promote further research interest.

Survey on research and development of on-orbit active debris removal methods

One possible avenue that may improve design against buckling is to recognise and account for the random nature of initial geometric imperfections introduced by manufacturing. This paper presents the application of a probabilistic methodology to the design and analysis of cylindrical shells under axial compression. Results from two cases are presented and compared: the first involves stringer-stiffened steel cylinders failing elastoplastically, whereas the second examines unstiffened composite cylinders buckling elastically. In both cases, the method is underpinned by statistical analysis of imperfections measured on nominally identical specimens. Non-linear FE analysis is used for strength assessment and the results of the statistical analysis are introduced in the imperfection modelling. It is demonstrated that the method has advantages over code design based on 'lower bound' curves, in terms of the calculated buckling loads but also in offering a systematic and rational way by which randomness in imperfections can be assessed.

Stochastic imperfection modelling in shell buckling studies

DE-ORBIT SAIL is a cubesat based drag sail for the de-orbiting of satellites in a low earth orbit It is scheduled for launch in late 2014 and will deploy a 25m² sail supported by deployable carbon fiber booms designed and manufactured by DLR This boom possesses a closed cross-section formed by two omega-shaped half-shells Due to this cross-sectional design the boom features a high torsional stiffness Thereby a high bending strength is achieved compared to other boom concepts for similar applications as the boom is less sensitive to flexural torsional buckling The boom concept selection is based on a detailed analysis of three types of deployable booms which differ in their cross-sectional design From this analysis the double-omega boom was determined as most suited for DE-ORBIT SAIL For the manufacturing of the booms a novel method is used where the booms are manufactured in an integral way in one piece

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The Boom Design of the De-Orbit Sail Satellite

One of the key challenges for small satellites is packaging and reliable deployment of structural booms and arrays used for power, communication, and scientific instruments. The lack of reliable and efficient boom and membrane deployment concepts for small satellites is addressed in this work through a collaborative project 
between NASA and DLR. The paper provides a state of the art overview on existing spacecraft deployable appendages, the special requirements for small satellites, and initial concepts for deployable booms and arrays needed for various small satellite applications. The goal is to enhance deployable boom predictability and ground testability, develop designs that are tolerant of manufacturing imperfections, and incorporate simple and reliable deployment systems.

/pdf/advanced-deployable-structural-systems-for-small-satellites-4pg66bm6k9.pdf

Advanced Deployable Structural Systems for Small Satellites

In recent years the German Aerospace Center (DLR) developed Gossamer deployment systems in different projects. DLR recently focused on the development of new deployable photovoltaic (PV) technologies that are suitable for generating 10's of kW per array as power requirements of spacecraft are getting more and more demanding. Possible space applications that may also require high power supply are missions using electric propulsion like interplanetary missions, placing of geostationary (GEO) satellites in their orbit or even more future oriented as space tugs or lightweight power generation on extraterrestrial infrastructures. The paper gives an overview about a feasibility study for a flexible solar array based on new thin-film photovoltaics. It is expected that the combination of new thin-film PV technologies, e.g. Copper Indium Gallium Selenide (CIGS) cells, together with Gossamer deployment technologies, could significantly increase the power availability for spacecraft. Based on a requirement analysis system concepts were evaluated. A focus is on the potential of CIGS PV combined with a two-dimensional deployment of the array and DLR's coilable Carbon Fiber Reinforced Plastic (CFRP) booms. Therefore, a concept based on crossed booms with a foldable PV membrane is considered as baseline for further developments. The array consists of rectangular PV generators that are interconnected by flexible Printed Circuit Board (PCB) harness. By a double folding technique these generators are laid on top of each other in such that the membrane can be extracted from its stowing box during the deployment in a controlled manner. Considering constantly increasing efficiencies of the CIGS PV combined with Gossamer structures, there is clear potential of reaching a very high specific power value exceeding that of conventional PV systems. Furthermore, the CIGS PV appears to be more radiation resistant and has already reached more than 20% efficiency in laboratories. Such efficiencies are expected to be achieved in the near future in a standard manufacturing process. DLR's research has the goal to develop a Gossamer Solar Array (GoSolAr) in order to investigate and exploit the described potential.

GoSolAr – A Gossamer Solar Array Concept for High Power Spacecraft Applications using flexible Photovoltaics

In recent years, the German Aerospace Center (DLR) developed Gossamer deployment systems in different projects. As power requirements of spacecraft are getting more and more demanding, DLR recently focused on the development of new deployable photovoltaic (PV) technologies that are suitable for generating 10’s of kW per array. Possible space applications that may also require high power supply are missions using electric propulsion such as interplanetary missions, placing of geostationary (GEO) satellites in their orbit or even more future oriented as space tugs or lightweight power generation on extra-terrestrial infrastructures. The paper gives an overview about a feasibility study for flexible solar arrays based on new thin-film photovoltaics. It is expected that the combination of new thin-film PV technologies, e.g., copper indium gallium selenide (CIGS) cells or gallium–arsenide (GaAs) cells, together with Gossamer deployment technologies, could significantly increase the power availability for spacecraft. Based on a requirement, analysis system concepts were evaluated. A focus is on the potential of CIGS PV combined with a two-dimensional deployment of the array and DLR’s coilable carbon fibre-reinforced plastic (CFRP) booms. Therefore, a concept based on crossed booms with a foldable PV membrane is considered as baseline for further developments. The array consists of rectangular PV generators that are interconnected by flexible printed circuit board (PCB) harness. By a double-folding technique, these generators are laid on top of each other in such that the membrane can be extracted from its stowing box during the deployment in a controlled manner. Considering constantly increasing efficiencies of the CIGS PV combined with Gossamer structures, there is clear potential of reaching a very high specific power value exceeding that of conventional PV systems. Furthermore, the CIGS PV appears to be more radiation resistant and has already reached more than 21% efficiency in laboratories. Such efficiencies are expected to be achieved in the near future in a standard manufacturing process. However, flexible, thin-film GaAs cells are also subject of consideration within GoSolAr. With this prospect, DLR’s research has the goal to develop a Gossamer Solar Array (GoSolAr) to exploit the described potential.

/pdf/concept-for-a-gossamer-solar-power-array-using-thin-film-4wsnf5memj.pdf

Martin E. Zander

Papers

Gossamer-1: Mission concept and technology for a controlled deployment of gossamer spacecraft

The Boom Design of the De-Orbit Sail Satellite

Advanced Deployable Structural Systems for Small Satellites

GoSolAr – A Gossamer Solar Array Concept for High Power Spacecraft Applications using flexible Photovoltaics

Concept for a Gossamer solar power array using thin-film photovoltaics