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  • 1.
    Amini, Kasra
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Centra, Linné Flow Center, FLOW. KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik.
    Janabadi, Ehsan Dehghani
    Univ Art, Fac Architecture & Urban Planning, Dept Architectural Technol, Tehran, Iran..
    Fayaz, Rima
    Univ Art, Fac Architecture & Urban Planning, Dept Architectural Technol, Tehran, Iran..
    Lighting and illumination investigation of long-term residence on Mars for the case of a set of designed Martian Habitat Units (MHUs)2022Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 192, s. 210-232Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Addressing the subject matter of human missions on Mars, the Martian Habitat Units (MHUs) are presented as a comprehensive solution. MHUs are designed in clusters of 10 units, each capable of serving as long-term habitats for 9 scientific crew members. The life-style requirements of the units are targeted at an imitation of cultural thriving life we all know of, and not a mere survival-type shelter expecting the first people to step foot on Mars. One aspect of many challenging issues to be addressed in such complex settings is the lighting and illuminance condition of the said habitats, which in the context of Mars, and generally deep space missions being far from the sun will certainly lead to an arduous task. To check the validity of the argument and assess the extent to which the natural light level available on the surface of Mars will be sufficient for the daily requirements of the crew and mission in terms of illuminance, the current manuscript presents thorough and detailed simulations and analyses on the availability evaluation of natural lighting in the site location of MHUs, namely Valles Marineris, Melas Chasma. In this paper solar irradiation parameters on Mars are calculated based on the previous research which resulted in global, direct and diffuse irradiance at 12 different Martian solar times. The simulations are distributed over the Martian year and its day-time, and for two extreme orientations of MHUs in their circular surrounding cluster, namely East/West and South/North units. The distribution of illuminance for each case, and trend comparison studies are then accompanied by numerical values and analyses on the percentage to which the natural lighting conditions on Mars have been shown to be sufficient as a fraction of the whole lighting load of the habitats, which is to be compensated using artificial sources. The corresponding values are shown to fall well in the range of 35-45% of the total lighting loads. Also, as the results of the simulations show, due to the consistency of the glazed parts of the designed facade through all exterior surface of the MHU, natural lighting sufficiency percentage does not show a significant difference between two simulated orientations. This fact further approves the circular orientation premise of the MHUs in their cluster.

  • 2.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laboratory experiments with a laser-based attachment mechanism for small bodiesInngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 3.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Laboratory experiments with a laser-based attachment mechanism for spacecraft at small bodies2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 189, s. 391-397Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present the results of two sets of experiments that investigate laser-based metal-to-rock attachment techniques. Asteroids and comets have low surface gravity which pose a challenge to landers with moving parts. Such parts can generate torques and forces which may tip the lander over or launch it into deep space. Thus, if a lander on a small body is to have moving parts, the spacecraft must be equipped with an anchoring mechanism. To this end, we sought to use a laser to melt and bind a piece of metal mimicking a part of a spacecraft to a rock mimicking the surface of a typical asteroid. In the first set of experiments, extra material was not fed in during the processing. The second set were performed using a standard wire feeder used in laser welding, which added metal to the experiment during processing. During the first experiments, we discovered that a traditional weld, where two melt pools mix and solidify to form a strong bond, was not possible—the melt pools would not mix, and when they did, the resulting weld was extremely brittle. The second set of experiments resulted in a physico-mechanical bond, where a hole was drilled with a laser, and a wire was melted and fed into the hole. These latter experiments were successful in forming bonds as strong as 115 N. Such an attachment mechanism can also be used to maneuver small boulders on asteroid surfaces, to redirect small, monolithic asteroids, or in space-debris removal.

  • 4.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Wanhainen, Christina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Laser-induced spallation of minerals common on asteroids2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 182, s. 325-331Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The ability to deflect dangerous small bodies in the Solar System or redirect profitable ones is a necessary and worthwhile challenge. One well-studied method to accomplish this is laser ablation, where solid surface material sublimates, and the escaping gas creates a momentum exchange. Alternatively, laser-induced spallation and sputtering could be a more efficient means of deflection, yet little research has studied these processes in detail. We used a 15-kW Ytterbium fiber laser on samples of olivine, pyroxene, and serpentine (minerals commonly found on asteroids) to induce spallation. We observed the process with a high-speed camera and illumination laser, and used X-ray micro-tomography to measure the size of the holes produced by the laser to determine material removal efficiency. We found that pyroxene will spallate at power densities between 1.5 and 6.0 kW cm−2, serpentine will also spallate at 13.7 kW cm−2, but olivine does not spallate at 1.5 kW cm−2 and higher power densities melt the sample. Laser-induced spallation of pyroxene and serpentine can be two- to three-times more energy efficient (volume removed per unit of absorbed energy) than laser-induced spattering, and over 40x more efficient than laser ablation.

    Fulltekst (pdf)
    fulltext
  • 5.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kuhn, Thomas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laufer, Rene
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Development of a competence ecosystem for the future space workforce: strategies, practices and recommendations from international master programs in northern Sweden2022Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 197, s. 46-52Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Requirements from the global labor market have substantially changed in recent years. Graduate and post-graduate students with excellent subject knowledge, deep understanding of modern working methods, technicaland higher-order thinking, engineering intuition and problem-solving skills are in great demand. They should also have professional skills such as well-developed abilities in communication and teamwork, usually in an international work environment. This review discusses the advantages of multidisciplinary study environment, educational strategies such as student-oriented teaching, project-based learning with its applicability to a“real-world” setting, active learning techniques, development of entrepreneurial skills, lessons learned and best practices from the international Master Program in Spacecraft Design and the Joint Master Program in SpaceScience and Technology – SpaceMaster at Luleå University of Technology in northern Sweden. The importance of complementarity between formal, informal and non-formal learning methods for science and engineering studentshas been specifically highlighted. Connections to the world of work, through active industry involvementin the education in a systematic way, e.g. External Advisory Board, shared services and facilities, joint projectsand supervision of Master and PhD students, is recognised as a key success factor for professional training. A structural combination of modern pedagogical tools, strategic partnership with industry, business entities, academic partners and up-to-date multidisciplinary labs creates the conceptual framework for a CompetenceEcosystem for fostering a new generation of space scientists and engineers.

    Fulltekst (pdf)
    fulltext
  • 6.
    Bazzocchi, Michael C.F.
    et al.
    Institute for Aerospace Studies, University of Toronto.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Comparative analysis of redirection methods for asteroid resource exploitation2016Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 120, s. 1-19Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An in-depth analysis and systematic comparison of asteroid redirection methods is performed within a resource exploitation framework using different assessment mechanisms. Through this framework, mission objectives and constraints are specified for the redirection of an asteroid from a near-Earth orbit to a stable orbit in the Earth-Moon system. The paper provides a detailed investigation of five redirection methods, i.e., ion beam, tugboat, gravity tractor, laser sublimation, and mass ejector, with respect to their capabilities for a redirection mission. A set of mission level criteria are utilized to assess the performance of each redirection method, and the means of assigning attributes to each criterion is discussed in detail. In addition, the uncertainty in physical characteristics of the asteroid population is quantified through the use of Monte Carlo analysis. The Monte Carlo simulation provides insight into the performance robustness of the redirection methods with respect to the targeted asteroid range. Lastly, the attributes for each redirection method are aggregated using three different multicriteria assessment approaches, i.e., the analytical hierarchy process, a utility-based approach, and a fuzzy aggregation mechanism. The results of each assessment approach as well as recommendations for further studies are discussed in detail.

  • 7.
    Bazzocchi, Michael C.F.
    et al.
    Institute for Aerospace Studies, University of Toronto, Toronto, Ontario, Canada.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Stochastic optimization of asteroid three-dimensional trajectory transfer2018Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 152, s. 705-718Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work, an approach to designing near-optimal nonplanar transfer trajectories for asteroids is introduced, taking into account the uncertainty in asteroid parameters. The approach is demonstrated using a specific known Near-Earth Asteroid (NEA) as a model for the transfer scenario. The designed trajectory redirects the NEA from its current orbit about the Sun to a new orbit in the Earth-Moon system. The approach utilizes a low-thrust redirection method, namely the ion beam method, to execute the transfer; however, the work can be extrapolated to most low-thrust redirection methods. Asteroid parameters, such as absolute magnitude, albedo and density, are modelled, and a Monte Carlo analysis is employed to investigate the redirection maneuver in light of the expected variation in parameters. The trajectory transfer is modelled in three dimensions through the use of pseudo-equinoctial shaping, and is subsequently optimized. Due to the large design space created by the 21 decision variables, the optimization is parsed into two main steps; first, a global optimization that employs a genetic algorithm, followed by a local optimization that utilizes sequential quadratic programming to refine the result from the global optimization. Lastly, the results of the Monte Carlo analysis for the near-optimal trajectory transfer of the NEA are discussed.

  • 8. Berg, H.E
    et al.
    Tesch, P.A
    Force and power characteristics of a resistive exercise device for use in space1998Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 42, s. 219-230Artikkel i tidsskrift (Fagfellevurdert)
  • 9. Bodin, Per
    et al.
    Noteborn, Ron
    Larsson, Robin
    Swedish Space Corporation, Sweden.
    Chasset, Camille
    System test results from the GNC experiments on the PRISMA in-orbit test bed2011Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 68, nr 7, s. 862-872Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The PRISMA in-orbit test bed will demonstrate guidance, navigation, and control strategies for spacecraft formation flying and rendezvous. The project is funded by the Swedish National Space Board and the prime contractor is the Swedish Space Corporation. The project is further supported by the German Aerospace Center, the Technical University of Denmark, and the French Space Agency. PRISMA was launched on June 15, 2010 and after three weeks of operations, all on-board systems and units have passed an initial commissioning phase. Separation of the two PRISMA satellites from each other is expected by mid-August 2010. PRISMA consists of two spacecraft: MAIN and TARGET. The MAIN spacecraft has full orbit control capability while TARGET is attitude controlled only. The Swedish Space Corporation is responsible for three groups of guidance, navigation, and control experiments. These experiments include GPS- and vision-based formation flying during which the spacecraft will fly in passive as well as forced motion. The three experiments are: autonomous formation flying, proximity operations with final approach/recede maneuvers, and autonomous rendezvous. This paper presents system test results from two of these experiments as obtained with the flight-ready system. The system tests consist of a series of simulations performed on the flight model spacecraft with a large amount of hardware in the loop.

  • 10.
    Bruhn, Fredrik
    et al.
    Uppsala University.
    Kratz, Henrik
    Uppsala University.
    Stenmark, Lars
    Uppsala University.
    Warell, Johan
    Uppsala University.
    Lagerkvist, Claes-Ingvar
    Uppsala University.
    Kaznov, Viktor
    Rotundus AB, Sweden.
    Jones, Jack
    California Institute of Technology, Jet Propulsion Laboratory.
    A preliminary design for a spherical inflatable microrover for planetary exploration2008Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 63, nr 5-6, s. 618-631Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Spherical Mobile Investigator for Planetary Surface (SMIPS) concept aims at making use of the latest developments within extreme miniaturization of space systems. The introduction of Microelectromechanical Systems (MEMSs) and higher level Multifunctional MicroSystems (MMSs) design solutions gives the robot high performance per weight unit. The untraditional spherical shape makes it easily maneuverable and thus provides a platform for scientific investigations of interplanetary bodies. Preliminary investigations of the SMIPS concept show several advantages over conventional robots and rovers in maneuverability, coverage, size, and mass. A locomotion proof-of-concept has been studied together with a new distributed on-board data system configuration. This paper discusses theoretical robot analysis, an overall concept, possible science, enabling technologies, and how to perform scientific investigations. A preliminary design of an inflatable multifunctional shell is proposed.

  • 11.
    Bruhn, Fredrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Warell, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Lagerkvist, Claes-Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Kaznov, Viktor
    Jones, Jack A
    Stenmark, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    A Preliminary Design for a Spherical Inflatable Microrover for Planetary Exploration2008Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 63, nr 5-6, s. 618-631Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Spherical Mobile Investigator for Planetary Surface (SMIPS) concept aims at making use of the latest developments within extreme miniaturization of space systems. The introduction of Microelectromechanical Systems (MEMSs) and higher level Multifunctional Microsystems (MMSs) design solutions gives the robot high performance per weight unit. The untraditional spherical shape makes it easily maneuverable and thus provides a platform for scientific investigations of interplanetary bodies. Preliminary investigations of the SMIPS concept show several advantages over conventional robots and rovers in maneuverability, coverage, size, and mass. A locomotion proof-of-concept has been Studied together with a new distributed on-board data system configuration. This paper discusses theoretical robot analysis, an overall concept, possible science, enabling technologies, and how to perform scientific investigations. A preliminary design of an inflatable multifunctional shell is proposed.

  • 12.
    Conte, Davide
    et al.
    The Pennsylvania State University.
    Di Carlo, Marilena
    University of Strathclyde.
    Budzyń, Dorota
    ESA/EAC, Linder Höhe, Cologne.
    Burgoyne, Hayden
    Analytical Space, Inc., Boston.
    Fries, Dan
    Georgia Institute of Technology.
    Grulich, Maria
    ESA/ESTEC.
    Heizmann, Sören
    Universität Stuttgart.
    Jethani, Henna
    Blue Origin.
    Lapôtre, Mathieu
    California Institute of Technology.
    Roos, Tobias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Castillo, Encarnación Serrano
    Università di Bologna.
    Scherrmann, Marcel
    ESA/ESTEC.
    Vieceli, Rhiannon
    New Mexico Institute of Mining and Technology.
    Wilson, Lee
    California Institute of Technology.
    Wynard, Christopher
    NASA Johnson Space Center.
    Advanced concept for a crewed mission to the martian moons2017Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 139, s. 545-563Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents the conceptual design of the IMaGInE (Innovative Mars Global International Exploration) Mission. The mission's objectives are to deliver a crew of four astronauts to the surface of Deimos and perform a robotic exploration mission to Phobos. Over the course of the 343 day mission during the years 2031 and 2032, the crew will perform surface excursions, technology demonstrations, In Situ Resource Utilization (ISRU) of the Martian moons, as well as site reconnaissance for future human exploration of Mars. This mission design makes use of an innovative hybrid propulsion concept (chemical and electric) to deliver a relatively low-mass reusable crewed spacecraft (approximately 100 mt) to cis-martian space. The crew makes use of torpor which minimizes launch payload mass. Green technologies are proposed as a stepping stone towards minimum environmental impact space access. The usage of beamed energy to power a grid of decentralized science stations is introduced, allowing for large scale characterization of the Martian environment. The low-thrust outbound and inbound trajectories are computed through the use of a direct method and a multiple shooting algorithm that considers various thrust and coast sequences to arrive at the final body with zero relative velocity. It is shown that the entire mission is rooted within the current NASA technology roadmap, ongoing scientific investments and feasible with an extrapolated NASA Budget. The presented mission won the 2016 Revolutionary Aerospace Systems Concepts - Academic Linkage (RASC-AL) competition.

  • 13. Delpech, M
    et al.
    Malbet, F
    Karlsson, Thomas
    Larsson, Robin
    OHB Sweden.
    Léger, A
    Jorgensen, J
    Flight demonstration of formation flying capabilities for future missions (NEAT Pathfinder)2014Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 105, nr 1, s. 82-94Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    PRISMA is a demonstration mission for formation-flying and on-orbit-servicing critical technologies that involves two spacecraft launched in low Earth orbit in June 2010 and still in operation. Funded by the Swedish National Space Board, PRISMA mission has been developed by OHB-Sweden (formerly Swedish Space Corporation) with important contributions from the German Aerospace Centre (DLR/GSOC), the French Space Agency (CNES), and the Technical University of Denmark (DTU). The paper focuses on the last CNES experiment achieved in September 2012 that was devoted to the preparation of future astrometry missions illustrated by the NEAT and mu-NEAT mission concepts. The experiment consisted of performing the type of formation maneuvers required to point the two-satellite axis to a celestial target and maintain it fixed during the observation period. Achieving inertial pointing for a LEO formation represented a new challenge given the numerous constraints from propellant usage to star tracker blinding. The paper presents the experiment objectives in relation with the NEAT/mu-NEAT mission concept, describes its main design features along with the guidance and control algorithms evolutions and discusses the results in terms of performances achieved during the two rehearsals.

  • 14.
    Felicetti, Leonard
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    A multi-spacecraft formation approach to space debris surveillance2016Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 127, s. 491-504Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper proposes a new mission concept devoted to the identification and tracking of space debris through observations made by multiple spacecraft. Specifically, a formation of spacecraft has been designed taking into account the characteristics and requirements of the utilized optical sensors as well as the constraints imposed by sun illumination and visibility conditions. The debris observations are then shared among the team of spacecraft, and processed onboard of a “hosting leader” to estimate the debris motion by means of Kalman filtering techniques. The primary contribution of this paper resides on the application of a distributed coordination architecture, which provides an autonomous and robust ability to dynamically form spacecraft teams once the target has been detected, and to dynamically build a processing network for the orbit determination of space debris. The team performance, in terms of accuracy, readiness and number of the detected objects, is discussed through numerical simulations.

  • 15.
    Felicetti, Leonard
    et al.
    University of Rome la Sapienza.
    Gasbarri, Paolo
    University of Rome la Sapienza.
    Pisculli, Andrea
    University of Rome la Sapienza.
    Sabatini, Marco
    University of Rome la Sapienza.
    Palmerini, Giovanni B.
    Sapienza Università di Roma, Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE).
    Design of robotic manipulators for orbit removal of spent launchers' stages2016Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 119, s. 118-130Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper deals with the main drivers for the design of a space manipulator aimed to the removal of the final stages which remain in Low Earth Orbit after releasing their payloads. At the scope, the different phases of a debris removal mission are considered, starting from the parking orbit where the servicing spacecraft equipped with the manipulator (chaser) waits for the call on duty, encompassing the approach to the target and its grasping and finally dealing with the dismissal of the captured object. The characteristics and requirements of each phase, in terms of torques to be applied to the joints of the manipulator(s) and to the forces to be generated via thrusters at the system level, are analysed. The number of robotic arms, the number of joints of each arm, and the torque level that each joint motor should supply are mainly defined by the grasping phase and the de-orbit phase. During the grasping, the tumbling target must be tracked with a large degree of robustness, and, to this aim, a redundant manipulator must be designed, so that its workspace can be as large as possible. On the other hand, increasing the degrees of freedom of a robotic arm means higher complexity and manufacturing costs. The number of arms depends also on the final de-orbit phase, in which the powerful apogee motor of the chaser satellite is ignited to change the composite system (chaser+target) orbit. The thrust, applied on the chaser, is transferred to the target by means of the manipulator(s): it is shown that a single robotic arm could not be sufficient to withstand the high stress acting during this phase. The torques at the joints required to maintain the arms in the desired configuration end up to be very high too, and the motors - as well as in general the structural elements of the arms - should be sized according to this phase of the mission

  • 16.
    Felicetti, Leonard
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Palmerini, Giovanni B.
    Sapienza Università di Roma, Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE), Scuola di Ingegneria Aerospaziale, Università di Roma La Sapienza.
    Analytical and numerical investigations on spacecraft formation control by using electrostatic forces2016Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 123, s. 455-469Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The paper investigates some analytical and numerical aspects of the formation control exploited by means of inter-spacecraft electrostatic actions. The analysis is based on the evaluation and check of the stability issues by using a sequence of purposely defined Lyapunov functions. The same Lyapunov approach can also define a specific under-actuate control strategy for controlling selected “virtual links” of the formation. Two different selection criteria for these links are then discussed, showing the implications on the control chain. An optimal charge distribution strategy, which assigns univocally the charges to all the spacecraft starting from the charge products computed by the control, is also presented and discussed. Numerical simulations prove the suitability of the proposed approach to a formation of 4 satellites.

  • 17. Filgas, Robert
    et al.
    Malich, Milan
    Pospíšil, Stanislav
    Bergmann, Benedikt
    Slavicek, Tomas
    Calzada-Diaz, Abigail
    Miniature semiconductor neutron spectrometer HardPix for surface mapping of lunar water2022Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 200, s. 620-625Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A current renaissance of lunar exploration enables to search for lunar water deposits directly on the surface of the Moon with robotic rovers. We present a novel miniature semiconductor neutron spectrometer capable of mapping the water deposits using non-invasive detection of neutrons created underground by cosmic rays and thermalized by hydrogen. This prospecting package consists of a radiation detector to monitor the cosmic rays background, a thermal/epithermal neutron detector to measure flux of neutrons moderated by water, and a gamma spectrometer suitable for monitoring local changes of major elemental components of the lunar regolith. Using miniature semiconductor detectors allows to deploy them even on small commercial rovers where resources are extremely limited. The prospecting package is being developed for ispace lunar rover and studied for ESA EL3 rover. It is based on Timepix pixel sensors, with space heritage onboard NASA, ESA and JAXA vessels.

  • 18.
    Fuglesang, Christer
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Miciano, Maria Garcia de Herreros
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Realistic sunshade system at L-1 for global temperature control2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 186, s. 269-279Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    So far, space-based geoengineering has rarely been studied from a practical point of view, considered unrealistic as a near-future alternative to fight climate change. This paper evaluates the feasibility of implementing a space sunshade in the vicinity of the first Lagrange point of the Sun-Earth system by the middle of the century. The analysis considers the necessary technological development, the possible trajectories for the shades, and an approximation of the size and cost of the system. It is strongly dependent on the possible optical properties of future solar sails, so an optimal and a more conservative alternative have been studied. With the latter, the shade will be formed by 1.5 x 10(9) sailcraft with a sail area of 2500 m(2) and a total mass of 8.3 x 10(10) kg. In the optimal case, the total mass is 3.4 x 10(10) kg. Each one of these sails will be launched to a 2000 km orbit, from where they will travel for about 600 days to the equilibrium point using solar radiation pressure. The total cost of the mission is estimated to be five to ten trillion dollars, based on a launch cost of US$50/kg. There are two main technological challenges for this to become a reality: the low TRL of the solar sails proposed and the necessary development in the launch vehicle industry given the dimensions of the mission.

  • 19.
    Gassot, Oriane
    et al.
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Panicucci, Paolo
    CNES, 18 Ave Edouard Belin, F-31400 Toulouse, France.;ISAE SUPAERO, 10 Ave Edouard Belin, F-31400 Toulouse, France.;Airbus Def & Space, 31 Rue Cosmonautes, F-31400 Toulouse, France..
    Acciarini, Giacomo
    Univ Strathclyde, Glasgow, Lanark, Scotland..
    Bates, Helena
    Nat Hist Museum, London, England.;Univ Oxford, Oxford, England..
    Caballero, Manel
    Univ Politecn Cataluna, Barcelona, Spain..
    Cambianica, Pamela
    INAF Astron Observ Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Dziewiecki, Maciej
    Wroclaw Univ Sci & Technol, Wroclaw, Poland..
    Dionnet, Zelia
    Univ Napoli Parthenope, Dip Sci & Tecnol, CDN IC4, I-80143 Naples, Italy..
    Enengl, Florine
    KTH Royal Inst Technol, Stockholm, Sweden..
    Gerig, Selina-Barbara
    Univ Bern, Phys Inst, Sidlerstr 5, CH-3012 Bern, Switzerland..
    Hessinger, Felix
    Luleå Univ Technol, Luleå, Sweden..
    Kissick, Lucy
    Univ Oxford, Oxford, England..
    Novak, Moritz
    Vienna Univ Technol, Vienna, Austria..
    Pellegrino, Carmine
    Tech Univ Munich, Inst Nanoelect, D-80333 Munich, Germany.;Airbus Def & Space Solar Array Engn & Design, D-82024 Taufkirchen, Germany..
    Pontoni, Angele
    Swedish Inst Space Phys, Kiruna, Sweden..
    Ribeiro, Tania M.
    Univ Porto, Fac Ciencias, IFIMUP, Rua Campo Alegre 687, P-4169007 Porto, Portugal.;Univ Porto, Fac Ciencias, Dept Fis & Astron, Rua Campo Alegre 687, P-4169007 Porto, Portugal..
    Riegler, Clemens
    JMU Wurzburg, Wurzburg, Germany..
    Berge, Nini
    Univ Orleans, CNRS, Lab Phys & Chim Environm & Espace, Orleans, France..
    Huber, Nikolaus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Hynek, Richard
    Univ West Bohemia, Plzen, Czech Republic..
    Kedziora, Bartosz
    Warsaw Univ Technol, Warsaw, Poland..
    Kiss, Adam
    Budapest Univ Technol & Econ, Budapest, Hungary..
    Martin, Maurice
    Univ Stuttgart, Stuttgart, Germany..
    Montilla, Javier Navarro
    INSA Toulouse, 135 Ave Rangueil, F-31400 Toulouse, France..
    Calathus: A sample-return mission to Ceres2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 181, s. 112-129Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ceres, as revealed by NASA's Dawn spacecraft, is an ancient, crater-saturated body dominated by low-albedo clays. Yet, localised sites display a bright, carbonate mineralogy that may be as young as 2 Myr. The largest of these bright regions (faculae) are found in the 92 km Occator Crater, and would have formed by the eruption of alkaline brines from a subsurface reservoir of fluids. The internal structure and surface chemistry suggest that Ceres is an extant host for a number of the known prerequisites for terrestrial biota, and as such, represents an accessible insight into a potentially habitable "ocean world". In this paper, the case and the means for a return mission to Ceres are outlined, presenting the Calathus mission to return to Earth a sample of the Occator Crater faculae for high-precision laboratory analyses. Calathus consists of an orbiter and a lander with an ascent module: the orbiter is equipped with a high-resolution camera, a thermal imager, and a radar; the lander contains a sampling arm, a camera, and an on-board gas chromatograph mass spectrometer; and the ascent module contains vessels for four cerean samples, collectively amounting to a maximum 40 g. Upon return to Earth, the samples would be characterised via high-precision analyses to understand the salt and organic composition of the Occator faculae, and from there to assess both the habitability and the evolution of a relict ocean world from the dawn of the Solar System.

  • 20.
    Gassot, Oriane
    et al.
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Panicucci, Paolo
    CNES, 18 Ave Edouard Belin, F-31400 Toulouse, France.;ISAE SUPAERO, 10 Ave Edouard Belin, F-31400 Toulouse, France.;Airbus Def & Space, 31 Rue Cosmonautes, F-31400 Toulouse, France..
    Acciarini, Giacomo
    Univ Strathclyde, Glasgow, Lanark, Scotland..
    Bates, Helena
    Nat Hist Museum, London, England.;Univ Oxford, Oxford, England..
    Caballero, Manel
    Univ Politecn Cataluna, Barcelona, Spain..
    Cambianica, Pamela
    INAF Astron Observ Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Dziewiecki, Maciej
    Wroclaw Univ Sci & Technol, Wroclaw, Poland..
    Dionnet, Zelia
    Univ Napoli Parthenope, Dip Sci & Tecnol, CDN IC4, I-80143 Naples, Italy..
    Enengl, Florine
    KTH, Skolan för teknikvetenskap (SCI).
    Gerig, Selina-Barbara
    Univ Bern, Phys Inst, Sidlerstr 5, CH-3012 Bern, Switzerland..
    Hessinger, Felix
    Luleå Univ Technol, Luleå, Sweden..
    Kissick, Lucy
    Univ Oxford, Oxford, England..
    Novak, Moritz
    Vienna Univ Technol, Vienna, Austria..
    Pellegrino, Carmine
    Tech Univ Munich, Inst Nanoelect, D-80333 Munich, Germany.;Airbus Def & Space Solar Array Engn & Design, D-82024 Taufkirchen, Germany..
    Pontoni, Angele
    Swedish Inst Space Phys, Kiruna, Sweden..
    Ribeiro, Tania M.
    Univ Porto, Fac Ciencias, IFIMUP, Rua Campo Alegre 687, P-4169007 Porto, Portugal.;Univ Porto, Fac Ciencias, Dept Fis & Astron, Rua Campo Alegre 687, P-4169007 Porto, Portugal..
    Riegler, Clemens
    JMU Wurzburg, Wurzburg, Germany..
    Berge, Nini
    Univ Orleans, CNRS, Lab Phys & Chim Environm & Espace, Orleans, France..
    Huber, Nikolaus
    Uppsala Univ, Uppsala, Sweden..
    Hynek, Richard
    Univ West Bohemia, Plzen, Czech Republic..
    Kedziora, Bartosz
    Warsaw Univ Technol, Warsaw, Poland..
    Kiss, Adam
    Budapest Univ Technol & Econ, Budapest, Hungary..
    Martin, Maurice
    Univ Stuttgart, Stuttgart, Germany..
    Montilla, Javier Navarro
    INSA Toulouse, 135 Ave Rangueil, F-31400 Toulouse, France..
    Calathus: A sample-return mission to Ceres2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 181, s. 112-129Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ceres, as revealed by NASA's Dawn spacecraft, is an ancient, crater-saturated body dominated by low-albedo clays. Yet, localised sites display a bright, carbonate mineralogy that may be as young as 2 Myr. The largest of these bright regions (faculae) are found in the 92 km Occator Crater, and would have formed by the eruption of alkaline brines from a subsurface reservoir of fluids. The internal structure and surface chemistry suggest that Ceres is an extant host for a number of the known prerequisites for terrestrial biota, and as such, represents an accessible insight into a potentially habitable "ocean world". In this paper, the case and the means for a return mission to Ceres are outlined, presenting the Calathus mission to return to Earth a sample of the Occator Crater faculae for high-precision laboratory analyses. Calathus consists of an orbiter and a lander with an ascent module: the orbiter is equipped with a high-resolution camera, a thermal imager, and a radar; the lander contains a sampling arm, a camera, and an on-board gas chromatograph mass spectrometer; and the ascent module contains vessels for four cerean samples, collectively amounting to a maximum 40 g. Upon return to Earth, the samples would be characterised via high-precision analyses to understand the salt and organic composition of the Occator faculae, and from there to assess both the habitability and the evolution of a relict ocean world from the dawn of the Solar System.

  • 21.
    Gassot, Oriane
    et al.
    Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France.
    Panicucci, Paolo
    CNES, 18 Avenue Edouard Belin, 31400, Toulouse, France; ISAE-SUPAERO, 10 Avenue Edouard Belin, 31400, Toulouse, France; Airbus Defence & Space, 31 Rue des Cosmonautes, 31400, Toulouse, France.
    Acciarini, Giacomo
    University of Strathclyde, UK.
    Bates, Helena
    Natural History Museum, London, UK; University of Oxford, UK.
    Caballero, Manel
    Universitat Politècnica de Catalunya, Spain.
    Cambianica, Pamela
    INAF - Astronomical Observatory of Padova, Vicolo dell’Osservatorio 5, 35122, Padova, Italy.
    Dziewiecki, Maciej
    Wroclaw University of Science and Technology, Poland.
    Dionnet, Zelia
    Università degli Studi di Napoli Parthenope, Italy.
    Enengl, Florine
    KTH Royal Institute of Technology, Sweden.
    Gerig, Selina-Barbara
    Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland.
    Hessinger, Felix
    Luleå tekniska universitet.
    Kissick, Lucy
    University of Oxford, UK.
    Novak, Moritz
    Vienna University of Technology, Austria.
    Pellegrino, Carmine
    Techincal University of Munich, Institute for Nanoelectronics, 80333, Munich, Germany.
    Pontoni, Angèle
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Ribeiro, Tânia M.
    IFIMUP and Departamento de Física e Astronomia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal.
    Riegler, Clemens
    JMU Würzburg, Germany.
    Berge, Nini
    Laboratoire de Physique et de Chimie de l’Environnement et de l’Espace, University of Orleans, CNRS, France.
    Huber, Nikolaus
    Uppsala University, Sweden.
    Hynek, Richard
    University of West Bohemia, Czech Republic.
    Kędziora, Bartosz
    Warsaw University of Technology, Poland.
    Kiss, Adam
    Budapest University of Technology and Economics, Hungary.
    Martin, Maurice
    University of Stuttgart, Germany.
    Navarro Montilla, Javier
    Institut National des Sciences Appliquées, France.
    Calathus: A sample-return mission to Ceres2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 181, s. 112-129Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ceres, as revealed by NASA's Dawn spacecraft, is an ancient, crater-saturated body dominated by low-albedo clays. Yet, localised sites display a bright, carbonate mineralogy that may be as young as 2 Myr. The largest of these bright regions (faculae) are found in the 92 km Occator Crater, and would have formed by the eruption of alkaline brines from a subsurface reservoir of fluids. The internal structure and surface chemistry suggest that Ceres is an extant host for a number of the known prerequisites for terrestrial biota, and as such, represents an accessible insight into a potentially habitable “ocean world”. In this paper, the case and the means for a return mission to Ceres are outlined, presenting the Calathus mission to return to Earth a sample of the Occator Crater faculae for high-precision laboratory analyses. Calathus consists of an orbiter and a lander with an ascent module: the orbiter is equipped with a high-resolution camera, a thermal imager, and a radar; the lander contains a sampling arm, a camera, and an on-board gas chromatograph mass spectrometer; and the ascent module contains vessels for four cerean samples, collectively amounting to a maximum 40 g. Upon return to Earth, the samples would be characterised via high-precision analyses to understand the salt and organic composition of the Occator faculae, and from there to assess both the habitability and the evolution of a relict ocean world from the dawn of the Solar System.

  • 22.
    Hakima, Houman
    et al.
    University of Toronto Institute for Aerospace Studies, 4925 Dufferin Street, Toronto.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Institute for Aerospace Studies, University of Toronto.
    Assessment of active methods for removal of LEO debris2018Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 144, s. 225-243Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper investigates the applicability of five active methods for removal of large low Earth orbit debris. The removal methods, namely net, laser, electrodynamic tether, ion beam shepherd, and robotic arm, are selected based on a set of high-level space mission constraints. Mission level criteria are then utilized to assess the performance of each redirection method in light of the results obtained from a Monte Carlo simulation. The simulation provides an insight into the removal time, performance robustness, and propellant mass criteria for the targeted debris range. The remaining attributes are quantified based on the models provided in the literature, which take into account several important parameters pertaining to each removal method. The means of assigning attributes to each assessment criterion is discussed in detail. A systematic comparison is performed using two different assessment schemes: Analytical Hierarchy Process and utility-based approach. A third assessment technique, namely the potential-loss analysis, is utilized to highlight the effect of risks in each removal methods

  • 23.
    Heldens, Jules C.
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Fridh, Jens
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Ostlund, Jan
    GKN Aerosp Sweden AB, Flygmotorvagen 1, SE-46181 Trollhättan, Sweden..
    On the characterization of methane in rocket nozzle cooling channels2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 186, s. 337-346Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In recent years there has been a growing interest in methane as an alternative rocket fuel due to its favourable specific gravity, storage temperature and thermal stability, in addition to its ability to support In-Situ Resource Utilization. Due to these properties methane supports the ongoing design trend of strategic reduction in system complexity and increase of reusability. The current work presents a first step in addressing the lack of information in open literature on the characteristics of methane under conditions found in rocket nozzle cooling channels, i.e. elevated inflow temperature and a high single sided heat load. A new experimental facility has been established at KTH Royal Institute of Technology in cooperation with GKN Aerospace, and as part of ESA's Future Launcher Preparatory Programme. This facility is shown to enable direct measurement of the Heat Transfer Coefficient (HTC) of methane under a range of conditions, with a limited uncertainty and good repeatability. For inflow temperatures of around 400 K, mass flows up to 15 g/s and pressures up to 3 MPa, it has been observed that the effect of single sided heating results in a significant development of the flow field, which influences the heat transfer in second half of the test section. This development results in an increase of the HTC towards the end of the cooling channel. No significant effect of the pressure on the HTC has been observed under the current experimental conditions.

  • 24.
    Israel Nazarious, Miracle
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Vakkada Ramachandran, Abhilash
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Zorzano, María-Paz
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Centro de Astrobiología (INTA-CSIC), Torrejon de Ardoz, Madrid, Spain.
    Martin-Torres, Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Calibration and preliminary tests of the Brine Observation Transition To Liquid Experiment on HABIT/ExoMars 2020 for demonstration of liquid water stability on Mars2019Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 162, s. 497-510Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The search for unequivocal proofs of liquid water on present day Mars is a prominent domain of research with implications on habitability and future Mars exploration. The HABIT (Habitability: Brines, Irradiation, and Temperature) instrument that will be on-board the ExoMars 2020 Surface Platform (ESA-IKI Roscosmos) will investigate the habitability of present day Mars, monitoring temperature, winds, dust conductivity, ultraviolet radiation and liquid water formation. One of the components of HABIT is the experiment BOTTLE (Brine Observation Transition To Liquid Experiment). The purposes of BOTTLE are to: (1) quantify the formation of transient liquid brines; (2) observe their stability over time under non-equilibrium conditions; and (3) serve as an In-Situ Resource Utilization (ISRU) technology demonstrator for water moisture capture. In this manuscript, we describe the calibration procedure of BOTTLE with standard concentrations of brines, the calibration function and the coefficients needed to interpret the observations on Mars.

    BOTTLE consists of six containers: four of them are filled with different deliquescent salts that have been found on Mars (calcium-perchlorate, magnesium-perchlorate, calcium-chloride, and sodium-perchlorate); and two containers that are open to the air, to collect atmospheric dust. The salts are exposed to the Martian environment through a high efficiency particulate air (HEPA) filter (to comply with planetary protection protocols). The deliquescence process will be monitored by observing the changes in electrical conductivity (EC) in each container: dehydrated salts show low EC, hydrated salts show medium EC and, liquid brines show high EC values. We report and interpret the preliminary test results using the BOTTLE engineering model in representative conditions; and we discuss how this concept can be adapted to other exploration missions.

    Our laboratory observations show that 1.2 g of anhydrous calcium-chloride captures about 3.7 g of liquid water as brine passing through various possible hydrate forms. This ISRU technology could potentially be the first attempt to understand the formation of transient liquid water on Mars and to develop self-sustaining in-situ water harvesting on Mars for future human and robotic missions.

  • 25.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Ogden, Sam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Smedfors, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Johansson, Linda
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Instrumentation and vehicle platform of a miniaturized submersible for exploration of terrestrial and extraterrestrial aqueous environments2012Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 79, s. 203-211Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An example of an extraterrestrial environment likely to support life is the vast liquid body believed to hide underneath the frozen crust of Jupiter's moon Europa. The hypothetical exploration of this, as well as the more accessible subglacial lakes on Earth, has been used as model applications for the development of a heavily miniaturized, yet qualified, submersible with the potential to be deployable either in itself through a long and narrow borehole or as the daughter craft of an ice-penetrating cryobot.

    Onboard the submersible, which is only 20 cm in length and 5 cm in diameter, accommodation of a versatile set of sensors and instruments capable of characterizing and imaging the surroundings, and even collecting water samples with microorganisms for return, is facilitated through the use of miniaturization technologies. For instance, together with a small camera, a laser-based, microoptic device enables the 3-D reconstruction of imaged objects for topographical measurements. As a complement, when the water is turbid or a longer range is wanted, the world's smallest side-scanning sonar, exhibiting centimeter resolution and a range of over 30 m, has been developed. The work on miniaturizing a CTD, which is a widely employed oceanographic instrument used to measure and correlate conductivity, temperature, and depth, has commenced. Furthermore, a device employing acoustics to trap microscopic particles and organisms, and, by this, enrich water samples, is under development. To ensure that the gathered samples are pristine until analyzed at the end of a mission, the device is equipped with high-pressure, latchable valves.

    Remote operation and transfer of measurement data and images, or even live streaming of video, is made possible through a kilometer-long fiber optic cable being reeled out from the vehicle underway and tethering it to a terminal. To extend the missions, the same fiber shall also be capable of charging the onboard batteries.

    In this paper, the vehicle and its subsystems are summarized. Subsystems essential for the vehicle's operation, e.g., hull structure, communication and power management, are treated separately from those of more mission-specific nature, like the instruments mentioned above.

  • 26.
    Kastinen, Daniel
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. Swedish Institute of Space Physics, Kiruna, Sweden.
    Vierinen, Juha
    Grydeland, Tom
    Kero, Johan
    Using radar beam-parks to characterize the Kosmos-1408 fragmentation event2023Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 202, s. 341-359Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We describe the use of radar beam-park experiments to characterize the space debris resulting from a recent fragmentation event, the deliberate demolition of the defunct Kosmos-1408 satellite. We identify the Kosmos-1408 fragments and present distribution of measurement parameters as well as proxy orbit parameters. We present and apply a novel technique to estimate the size of objects by matching the signal to noise ratio of the detection to the radiation pattern of the radar. With this method we estimate the size distribution of the debris cloud. We also demonstrate how a pair of beam-park observations can be used to perform a crude, yet seemingly reliable, initial orbit determination. Finally, we present followup observations ∼5 months after the fragmentation that show a still compact cloud of debris.

    Fulltekst (pdf)
    fulltext
  • 27.
    Kozynchenko, Alexander I
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Predictive guidance algorithms for maximal downrange maneuvrability with application to low-lift re-entry2009Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 64, nr 7-8, s. 770-777Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The paper concerns the general problem of a bounded final state control of non-linear dynamic systems with reference to near-optimal predictive guidance for low lift-to-drag ratio re-entry vehicles. More specifically, it addresses deriving guidance strategies capable to provide a maximal downrange maneuvrability for a maximal remaining flight time. Such robust, “guaranteed”, or assured, guidance keeps the remaining range-to-go to be coincident with the center of instant attainability domain. The paper discusses the existing guaranteed guidance strategy, and presents more general approach that provides an on-board planning of the entry trajectory, thus giving future state and control profiles. As a consequence the proposed guidance law is able to satisfy not only specified terminal conditions but also typical inequality constraints such as the maximal load factor and heat load. Computer simulations show that the algorithm can generate the feasible trajectories with equal downrange margins, using simple two-parametric families of control functions.

  • 28.
    Lehner, B.A.E.
    et al.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands.
    Schlechten, J.
    Department of Computer Science, University of Geneva, Carouge, Switzerland.
    Filosa, A.
    Department of Aerospace Science and Technology (DAST), Politecnico di Milano, Milano, Italy.
    Canals Pou, A.
    Department of Materials Science and Metallurgy (CMEM), ETSEIB, Universitat Politècnica de Catalunya (UPC), Barcelona, Spain.
    Mazzotta, D.G.
    Department of Mechanical and Aerospace Engineering (DIMEAS), Politecnico di Torino, Torino, Italy.
    Spina, Francesco
    Luleå tekniska universitet.
    Teeney, L.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands. Department of Computer Science, University of Geneva, Carouge, Switzerland.
    Snyder, J.
    USRA / NASA Ames Research Center, Moffett Field, USA.
    Tjon, S.Y.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands.
    Meyer, A.S.
    Department of Biology, University of Rochester, Rochester, USA.
    Brouns, S.J.J.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands.
    Cowley, A.
    European Astronaut Centre (EAC), European Space Agency (ESA), Cologne, Germany.
    Rothschild, L.J.
    NASA Ames Research Center, Moffett Field, USA.
    End-to-end mission design for microbial ISRU activities as preparation for a moon village2019Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 162, s. 216-226Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In situ resource utilization (ISRU) increasingly features as an element of human long-term exploration and settlement missions to the lunar surface. In this study, all requirements to test a novel, biological approach for ISRU are validated, and an end-to-end mission architecture is proposed. The general mission consists of a lander with a fully autonomous bioreactor able to process lunar regolith and extract elemental iron. The elemental iron could either be stored or directly utilized to generate iron wires or construction material. To maximize the success rate of this mission, potential landing sites for future missions are studied, and technical details (thermal radiation, shielding, power-supply) are analyzed. The final section will assess the potential mission architecture (orbit, rocket, lander, timeframe). This design might not only be one step further towards an international “Moon Village”, but may also enable similar missions to ultimately colonize Mars and further explore our solar system.

  • 29.
    Lehtinen, Tuomas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Bellome, Andrea
    Space Research Group, Cranfield University, Cranfield, United Kingdom.
    Sánchez, Joan-Pau
    Space Research Group, Cranfield University, Cranfield, United Kingdom.
    Icarus: In-situ monitoring of the surface degradation on a near-Sun asteroid2021Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 186, s. 98-108Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Icarus is a mission concept designed to record the activity of an asteroid during a close encounter with the Sun. The primary science goal of the mission is to unravel the nontrivial mechanism(s) that destroy asteroids on orbits with small perihelion distances. Understanding the destruction mechanism(s) allows us to constrain the bulk composition and interior structure of asteroids in general. The Icarus mission does not only aim to achieve its science goals but also functions as a technical demonstration of what a low-cost space mission can do. The proposed space segment will include a single spacecraft capable of surviving and operating in the harsh environment near the Sun. The spacecraft design relies on the heritage of missions such as Rosetta, MESSENGER, Parker Solar Probe, BepiColombo, and Solar Orbiter. The spacecraft will rendezvous with an asteroid during its perihelion passage and records the changes taking place on the asteroid’s surface. The primary scientific payload has to be capable of imaging the asteroid’s surface in high resolution using visual and near-infrared channels as well as collecting and analyzing particles that are ejected from the asteroid. The payload bay also allows for additional payloads relating to, for example, solar research. The Icarus spacecraft and the planned payloads have high technology readiness levels and the mission is aimed to fit the programmatic and cost constraints of the F1 mission (Comet Interceptor) by the European Space Agency. Considering the challenging nature of the Icarus trajectory and the fact that the next F-class mission opportunity (F2) is yet to be announced, we conclude that Icarus is feasible as an F-class mission when certain constraints such as a suitable launch configuration are met. A larger mission class, such as the M class by the European Space Agency, would be feasible in all circumstances.

  • 30.
    Liberman, M. A.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi.
    Ivanov, M. F.
    Kiverin, A. D.
    Kuznetsov, M. S.
    Chukalovsky, A. A.
    Rakhimova, T. V.
    Deflagration-to-detonation transition in highly reactive combustible mixtures2010Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 67, nr 7-8, s. 688-701Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The paper presents experimental, theoretical, and numerical studies of deflagration-to-detonation transition (DDT) in highly reactive hydrogen-oxygen and ethylene-oxygen mixtures. Two-dimensional reactive Navier-Stokes equations for a hydrogen-oxygen gaseous mixture including the effects of viscosity, thermal conduction, molecular diffusion, and a detailed chemical reaction mechanism are solved numerically. It is found that mechanism of DDT is entirely determined by the features of the flame acceleration in tubes with no-slip walls. The experiments and computations show three distinct stages of the process: (1) the flame accelerates exponentially producing shock waves far ahead from the flame, (2) the flame acceleration decreases and shocks are formed directly on the flame surface, and (3) the final third stage of the actual transition to a detonation. During the second stage a compressed and heated pocket of unreacted gas adjacent ahead to the flame the preheat zone is forming and the compressed unreacted mixture entering the flame produces large amplitude pressure pulse. The increase of pressure enhances reaction rate and due to a positive feedback between the pressure peak and the reaction the pressure peak grows exponentially, steepens into a strong shock that is coupled with the reaction zone forming the overdriven detonation wave. The proposed new physical mechanism of DDT highlights the features of flame acceleration in tubes with no-slip walls, which is the key factor of the DDT origin.

  • 31.
    Liberman, Michael A.
    et al.
    Stockholms universitet, Nordiska institutet för teoretisk fysik (Nordita).
    Ivanov, M. F.
    Kiverin, A. D.
    Radiation heat transfer in particle-laden gaseous flame: Flame acceleration and triggering detonation2015Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 115, s. 82-93Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study we examine influence of the radiation heat transfer on the combustion regimes in the mixture, formed by suspension of fine inert particles in hydrogen gas. The gaseous phase is assumed to be transparent for the thermal radiation, while the radiant heat absorbed by the particles is then lost by conduction to the surrounding gas. The particles and gas ahead of the flame is assumed to be heated by radiation from the original flame. It is shown that the maximum temperature increase due to the radiation preheating becomes larger for a flame with lower velocity. For a flame with small enough velocity temperature of the radiation preheating may exceed the crossover temperature, so that the radiation heat transfer may become a dominant mechanism of the flame propagation. In the case of non-uniform distribution of particles, the temperature gradient formed due to the radiation preheating can initiate either deflagration or detonation ahead of the original flame via the Zel'dovich's gradient mechanism. The initiated combustion regime ignited in the preheat zone ahead of the flame depends on the radiation absorption length and on the steepness of the formed temperature gradient. Scenario of the detonation triggering via the temperature gradient mechanism formed due to the radiation preheating is plausible explanation of the transition to detonation in Supernovae Type la explosion.

  • 32.
    Liberman, Michael A.
    et al.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Ivanov, M. F.
    Kiverin, A. D.
    Radiation heat transfer in particle-laden gaseous flame: Flame acceleration and triggering detonation2015Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 115, s. 82-93Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study we examine influence of the radiation heat transfer on the combustion regimes in the mixture, formed by suspension of fine inert particles in hydrogen gas. The gaseous phase is assumed to be transparent for the thermal radiation, while the radiant heat absorbed by the particles is then lost by conduction to the surrounding gas. The particles and gas ahead of the flame is assumed to be heated by radiation from the original flame. It is shown that the maximum temperature increase due to the radiation preheating becomes larger for a flame with lower velocity. For a flame with small enough velocity temperature of the radiation preheating may exceed the crossover temperature, so that the radiation heat transfer may become a dominant mechanism of the flame propagation. In the case of non-uniform distribution of particles, the temperature gradient formed due to the radiation preheating can initiate either deflagration or detonation ahead of the original flame via the Zel'dovich's gradient mechanism. The initiated combustion regime ignited in the preheat zone ahead of the flame depends on the radiation absorption length and on the steepness of the formed temperature gradient. Scenario of the detonation triggering via the temperature gradient mechanism formed due to the radiation preheating is plausible explanation of the transition to detonation in Supernovae Type la explosion. (C) 2015 IAA. Published by Elsevier Ltd. All rights reserved.

  • 33.
    Mao, Huina
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Sinn, Thomas
    Vasile, Massimiliano
    Tibert, Gunnar
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Post-launch analysis of the deployment dynamics of a space web sounding rocket experiment2016Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 127, s. 345-358Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lightweight deployable space webs have been proposed as platforms or frames for a construction of structures in space where centrifugal forces enable deployment and stabilization. The Suaineadh project was aimed to deploy a 2 x 2 m2 space web by centrifugal forces in milli-gravity conditions and act as a test bed for the space web technology. Data from former sounding rocket experiments, ground tests and simulations were used to design the structure, the folding pattern and control parameters. A developed control law and a reaction wheel were used to control the deployment. After ejection from the rocket, the web was deployed but entanglements occurred since the web did not start to deploy at the specified angular velocity. The deployment dynamics was reconstructed from the information recorded in inertial measurement units and cameras. The nonlinear torque of the motor used to drive the reaction wheel was calculated from the results. Simulations show that if the Suaineadh started to deploy at the specified angular velocity, the web would most likely have been deployed and stabilized in space by the motor, reaction wheel and controller used in the experiment.

  • 34.
    Matelli, José Alexandre
    et al.
    São Paulo State University (UNESP), School of Engineering, Department of Energy, Av. Ariberto Pereira da Cunha, Guaratinguetá, SP, Brazil.
    Goebel, Kai
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik. NASA Ames Research Center, Intelligent Systems Division, Discovery and Systems Health, Moffett Field, CA.
    Resilience evaluation of the environmental control and life support system of a spacecraft for deep space travel2018Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 152, s. 360-369Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In deep space manned travels, the crew life will be totally dependent on the environment control and life support system of the spacecraft. A life-support system for manned missions is a set of technologies to regenerate the basic life-support elements, such as oxygen and water, which makes resilience a paramount feature of this system. The resilience of a complex engineered system is the ability of the system to withstand failures, continue operating and recover from those failures with minimum disruption. Resilient design is a new design framework on which the main goal is to quantify system resilience upfront in order to guide the design team during the conceptual design stage. In this article, we present a tool that combines a rule-based approach with a Monte Carlo-based approach to evaluate the resilience of a proposed environment control and life support system designed for deep space travel. Based on the results found, we explore a few design alternatives in order to increase system resilience.

  • 35.
    Mathanlal, Thasshwin
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Israel Nazarious, Miracle
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Vakkada Ramachandran, Abhilash
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Zorzano, Maria-Paz
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Centro de Astrobiología (CSIC-INTA), Torrejon de Ardoz, 28850, Madrid, Spain.
    Martin-Torres, Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), 18100, Granada, Spain.
    Rettberg, Petra
    German Aerospace Center, Institute of Aerospace Medicine, Radiation Biology, Linder Höhe, 51147, Köln, Germany.
    Implementing bioburden reduction and control on the deliquescent hydrogel of the HABIT/ExoMars 2020 instrument2020Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 173, s. 232-239Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The HabitAbility: Brines, Irradiation and Temperature (HABIT) instrument will be part of the ExoMars 2020 mission (ESA/Roscosmos) and will be the first European In-situ Resource Utilization (ISRU) instrument capable of producing liquid water on Mars. HABIT is composed by two modules: Environmental Package (EnvPack) and Brine Observation Transition To Liquid Experiment (BOTTLE). EnvPack will help to study the current habitability conditions on Mars investigating the air and surface thermal ranges and Ultraviolet (UV) irradiance; and BOTTLE is a container with four independent vessels housing deliquescent salts, which are known to be present on Mars, where the liquid water will be produced after deliquescence. In order to prevent capillarity of deliquescent or hydrated salts, a mixture of deliquescent salts with Super Absorbent Polymer (SAP) based on polyacrylamide is utilized. This mixture has deliquescent and hydrogel properties and can be reused by applying a thermal cycle, complying thus with the purpose of the instrument. A High Efficiency Particulate Air (HEPA) grade filter made of polytetrafluroethylene (PTFE) porous membrane sandwiched between spunbounded non-woven fabric stands as a physical barrier allowing interaction between the gaseous molecules of the Martian atmosphere and the salt mixtures, and at the same time preventing the passage of any potential biological contamination from the cells to the outside or vice-versa. In addition to the physical barrier, a strict bioburden reduction and analysis procedure is applied to the hardware and the contained salt mixtures adhering to the European Cooperation for Space Standardization protocol of microbial examination of flight hardware (ECSS-Q-ST-70-55C). The deliquescent salts and the SAP products need to be properly treated independently to adhere to the planetary protection protocols. In this manuscript, we describe the bioburden reduction process utilized to sterilize the salt mixtures in BOTTLE and the assays adopted to validate the sterilization. We also describe the construction of a low-cost, portable ISO 7 cleanroom tent, exclusively designed for planetary protection tests. The sterilization process involves Dry Heat Microbial Reduction (DHMR) of the deliquescent salts and the SAP mixtures. The performance of SAP after DHMR is validated to ensure its working efficiency after sterilization. A slightly modified version of the standard swab assay is used in the validation process and a comparison is made between samples exposed to a thermal shock treatment and those without thermal shock, to determine the best assay to be applied for future space hardware utilizing such salt mixtures for planetary investigation and In-Situ Resource Utilization (ISRU). The demonstration of the compatibility of these products with the processes commonly required for space applications has implications for the future exploration of Mars.

  • 36. Mege, Daniel
    et al.
    Gurgurewicz, Joanna
    Grygorczuk, Jerzy
    Wisniewski, Lukasz
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    The Highland Terrain Hopper (HOPTER): Concept and usecases of a new locomotion system for the exploration of lowgravity Solar System bodies2016Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 121, s. 200-220Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Comprehensive understanding of the principles governing the geological activity of theEarth was obtained in continental and oceanic mountains. It is not expected that theprinciples governing the overall geologic activity and evolution of other planetary bodiessuch as Mars will be understood if exploration is limited to nearlyflat terrains, eitherimposed by the used exploration platform capabilities, the risk of getting stuck, or by thetime required to cross the border of a landing ellipse. Surface exploration of mountains isadditionally to be coupled to two- or three-dimensional geophysical surveys to correlatethe surface observations with deeper processes. On the small bodies where ultra-lowgravity prevails, the weight of wheel-driven platforms is not sufficient to generate thefriction at the contact with the ground that is required to trigger motion of the roverrelative to the ground. Under such circumstances, hopping is one of the mobility solutions.We present a new locomotion system, the hopter platform, which is adapted to thesechallenges on Solar System bodies having a gravityfield lower than on Earth. The hopter isa robust, versatile and highly manoeuvrable platform based on simple mechanical con-cepts that accurately jumps to distances of metres to tens of metres and more, dependingon the gravityfield of the studied body. Its low mass of 10 kg (including up to 3 kg ofminiaturised payload), makes it possible to simultaneously launch several hopters to workas a fractionated explorer at a very competitive cost. After reviewing the payload that maybe placed onboard hopters, we illustrate the scientific capabilities of hopters and hopternetworks in performing basic geologic observations at distinct study sites in a variety ofgeological environments, obtaining data along steep geological cross sections, surveyinggeophysical anomalies in the subsurface, prospecting resources, monitoring micro-environments, meteorological events, and geodetic deformation, or characterizing dustactivity on Mars, the Moon, and Phobos.

  • 37.
    Muralidharan, Vijay
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Concurrent rendezvous control of underactuated spacecraft2017Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 138, s. 28-42Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concurrent control of spacecraft equipped with one-axis unilateral thruster and three-axis attitude actuator is considered in this paper. The proposed control law utilizes attitude control channels along with the single thrust force concurrently, for three-dimensional trajectory tracking and rendezvous with a target object. The concurrent controller also achieves orbital transfer to low Earth orbits with long range separation. To demonstrate the orbit transfer capabilities of the concurrent controller, a smooth elliptical orbit transfer trajectory for co-planar circular orbits is designed. The velocity change and energy consumption of the designed orbit transfer trajectory is observed to be equivalent to that of Hohmann transfer.

  • 38.
    Mège, Daniel
    et al.
    Polish Acad Sci, Space Res Ctr, Bartycka St 18A, PL-00716 Warsaw, Poland.;Univ Nantes, Lab Planetol & Geodynam, CNRS UMR 6112, BP 92208, F-44322 Nantes 3, France.;OSUNA, CNRS, UMS 3281, Lyon, France..
    Gurgurewicz, Joanna
    Polish Acad Sci, Space Res Ctr, Bartycka St 18A, PL-00716 Warsaw, Poland.;Polish Acad Sci, Inst Geol Sci, Res Ctr Wroclaw, Podwale St 75, PL-50449 Wroclaw, Poland..
    Grygorczuk, Jerzy
    Polish Acad Sci, Space Res Ctr, Bartycka St 18A, PL-00716 Warsaw, Poland.;Astronika Sp Zoo, Bartycka St 18, PL-00716 Warsaw, Poland..
    Wisniewski, Lukasz
    Polish Acad Sci, Space Res Ctr, Bartycka St 18A, PL-00716 Warsaw, Poland.;Astronika Sp Zoo, Bartycka St 18, PL-00716 Warsaw, Poland..
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    The Highland Terrain Hopper (HOPTER): Concept and use cases of a new locomotion system for the exploration of low gravity Solar System bodies2016Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 121, s. 200-220Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Comprehensive understanding of the principles governing the geological activity of the Earth was obtained in continental and oceanic mountains. It is not expected that the principles governing the overall geologic activity and evolution of other planetary bodies such as Mars will be understood if exploration is limited to nearly flat terrains, either imposed by the used exploration platform capabilities, the risk of getting stuck, or by the time required to cross the border of a landing ellipse. Surface exploration of mountains is additionally to be coupled to two- or three-dimensional geophysical surveys to correlate the surface observations with deeper processes. On the small bodies where ultra-low gravity prevails, the weight of wheel-driven platforms is not sufficient to generate the friction at the contact with the ground that is required to trigger motion of the rover relative to the ground. Under such circumstances, hopping is one of the mobility solutions. We present a new locomotion system, the hopter platform, which is adapted to these challenges on Solar System bodies having a gravity field lower than on Earth. The hopter is a robust, versatile and highly manoeuvrable platform based on simple mechanical concepts that accurately jumps to distances of metres to tens of metres and more, depending on the gravity field of the studied body. Its low mass of 10 kg (including up to 3 kg of miniaturised payload), makes it possible to simultaneously launch several hopters to work as a fractionated explorer at a very competitive cost. After reviewing the payload that may be placed onboard hopters, we illustrate the scientific capabilities of hopters and hopter networks in performing basic geologic observations at distinct study sites in a variety of geological environments, obtaining data along steep geological cross sections, surveying geophysical anomalies in the subsurface, prospecting resources, monitoring micro environments, meteorological events, and geodetic deformation, or characterizing dust activity on Mars, the Moon, and Phobos.

  • 39.
    Ribeiro, Tânia M.
    et al.
    Univ Porto, Fac Ciencias, Dept Fis & Astron, Inst Fis Mat Avancados Nanotecnol & Foton, Rua Campo Alegre s-n, P-4169007 Porto, Portugal..
    D'Ambrosio, Andrea
    Univ Arizona, Dept Syst & Ind Engn, 1127 E James E Rogers Way, Tucson, AZ 85721 USA..
    Dominguez Calabuig, Guillermo J.
    German Aerosp Ctr DLR, Cologne, Germany..
    Athanasopoulos, Dimitrios
    Natl & Kapodistrian Univ Athens, Dept Phys, Sect Astrophys Astron & Mech, GR-15784 Athens, Greece..
    Bates, Helena
    Nat Hist Museum, Planetary Mat Grp, London SW7 5BD, England..
    Riegler, Clemens
    JMU Wurzburg, Comp Sci 8, Space Engn, D-97074 Wurzburg, Germany..
    Gassot, Oriane
    Univ Grenoble Alpes, IPAG, CNRS, F-38000 Grenoble, France..
    Gerig, Selina-Barbara
    Univ Bern, Phys Inst, Sidlerstr 5, CH-3012 Bern, Switzerland..
    Gómez-González, Juan L.
    Comillas Pontifical Univ, Inst Res Technol, ICAI, C Sta Cruz Marcenado 26, Madrid 28015, Spain..
    Huber, Nikolaus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Seton, Ragnar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap, Mikrosystemteknik.
    Magalhães, Tiago E. C.
    Univ Porto, Fac Ciencias, Dept Fis & Astron, Inst Fis Mat Avancados Nanotecnol & Foton, Rua Campo Alegre s-n, P-4169007 Porto, Portugal..
    CARINA: A near-Earth D-type asteroid sample return mission2023Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 212, s. 213-225Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    D-type asteroids are among the most primitive small bodies of the solar system. Believed to be formed in the outer solar system, a minor fraction of these faint objects can be found in the near-Earth region. Some were suspected to be extinct comets disguised as asteroids. If D-type near-Earth asteroids could represent extinct comets, they would offer us a unique opportunity to investigate the relationship between two classes of minor bodies in our solar system. To provide new insights into D-type asteroids' composition and dynamical evolution and the possible relation with comets, we introduce the mission concept CARINA (Comet Asteroid Relation INvestigation and Analysis). CARINA will visit and collect a sample from the asteroid 2002 AT4 and address key scientific questions related to our understanding of the early solar system evolution, and the origins of water and life on the early Earth. This paper outlines the scientific motivation and the means for the sample return. The spacecraft is equipped with a sampling ring to perform in-situ analysis and to collect, in a "touch and go"manner, samples from the surface and subsurface of the asteroid. A capsule is expected to return the samples to Earth in pristine conditions for detailed and extended analysis. These would represent a rare contribution to our meteorite collection since it would be the first time that material from a D class asteroid would be collected.

    Fulltekst (pdf)
    fulltext
  • 40.
    Satpute, Sumeet
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. University of Toronto, Toronto, Canada.
    Concurrent co-location maneuver planning for geostationary satellites2019Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 163, nr Part B, s. 211-224Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper details the development of a planning algorithm for multiple co-located geostationary satellites to perform station keeping and momentum unloading maneuvers concurrently. The objective is to minimize the overall fuel consumption while guaranteeing a safe separation distance between the satellites within a specific geostationary slot, as well as managing their stored angular momentum to maintain their nadir pointing orientation. The algorithm adopts the leader-follower architecture to define relative orbital elements of the satellites equipped with four gimbaled on-off electric thrusters, and solves a convex optimization problem with inequality constraints, including momentum unloading requirements, to determine the optimal maneuvers. The proposed algorithm is verified, in terms of fuel consumption, constraints enforcement and satellites performance, using numerical simulations that take into account dominant perturbations in the geostationary environment.

  • 41.
    Schmidt, Jens
    et al.
    Center for Astrophysics, Space Physics and Engineering Research (CASPER), Baylor University, 100 Research Pkwy, Waco, TX, USA. Institute of Space Systems, University of Stuttgart, Pfaffenwaldring 29, 70569 Stuttgart, Germany.
    Laufer, René
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Hyde, Truell
    Center for Astrophysics, Space Physics and Engineering Research (CASPER), Baylor University, 100 Research Pkwy, Waco, TX, USA.
    Herdrich, Georg
    Institute of Space Systems, University of Stuttgart, Pfaffenwaldring 29, 70569 Stuttgart, Germany.
    The IPG6-B as a research facility to support future development of electric propulsion2022Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 196, s. 432-441Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The inductively-heated plasma generator IPG6-B at Baylor University has been established and characterized in previous years for use as a flexible experimental research facility across multiple applications. The system uses a similar plasma generator design to its twin-facilities at the University of Stuttgart (IPG6-S) and the University of Kentucky (IPG6-UKY). The similarity between these three devices offers the advantage to reproduce results and provides comparability to achieve cross-referencing and verification. Sub- and supersonic flow conditions for Mach numbers between Ma = 0.3 — 1.4 have been characterized for air, argon, helium and nitrogen using a pitot probe. Overall power coupling efficiency as well as specific bulk enthalpy of the flow have been determined by calorimeter measurements to be between η = 0.05 — 0.45 and hs = 5 — 35 MJ kg-1 respectively depending on gas type and pressure. Electron temperatures of Te = 1 — 2 eV and densities ne = 1018 — 1020 m-3 have been measured using an electrostatic probe system. At Baylor University, laboratory experiments in the areas of astrophysics, geophysics as well as fundamental research on complex (dusty) plasmas are planned. The study of fundamental processes in low-temperature plasmas connects directly to electric propulsion systems. Most recent experiments include the study of dusty plasmas and astrophysical phenomena and the interaction of charged dust with electric and magnetic fields. In this case, dust can be used as a diagnostic for such fields and can reveal essential information of the magneto-hydrodynamics in low-temperature plasmas. Although some of these goals require further advancement of the facility, it is proposed that several phenomena relevant to electric propulsion as well as to other fields of plasma physics can be studied using the existing facility.

  • 42. Straube, Ulrich
    et al.
    Berger, Thomas
    Reitz, Guenther
    Facius, Rainer
    Fuglesang, Christer
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Reiter, Thomas
    Damann, Volker
    Tognini, Michel
    Operational radiation protection for astronauts and cosmonauts and correlated activities of ESA Medical Operations2010Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 66, nr 7-8, s. 963-973Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Since the early times of human spaceflight radiation has been, besides the influence of microgravity on the human body, recognized as a main health concern to astronauts and cosmonauts. The radiation environment that the crew experiences during spaceflight differs significantly to that found on earth due to particles of greater potential for biological damage. Highly energetic charged particles, such as protons, helium nuclei ("alpha particles") and heavier ions up to iron, originating from several sources, as well as protons and electrons trapped in the Earth's radiation belts, are the main contributors. The exposure that the crew receives during a spaceflight significantly exceeds exposures routinely received by terrestrial radiation workers. The European Space Agency's (ESA) Astronaut Center (EAC) in Cologne, Germany, is home of the European Astronaut Corps. Part of the EAC is the Crew Medical Support Office (CMSO or HSF-AM) responsible for ensuring the health and well-being of the European Astronauts. A sequence of activities is conducted to protect astronauts and cosmonauts health, including those aiming to mitigate adverse effects of space radiation. All health related activities are part of a multinational Medical Operations (MedOps) concept, which is executed by the different Space Agencies participating in the human spaceflight program of the International Space Station (ISS). This article will give an introduction to the current measures used for radiation monitoring and protection of astronauts and cosmonauts. The operational guidelines that shall ensure proper implementation and execution of those radiation protection measures will be addressed. Operational hardware for passive and active radiation monitoring and for personal dosimetry, as well as the operational procedures that are applied, are described.

  • 43.
    Villarroel, Beatriz
    et al.
    Stockholms universitet, Nordiska institutet för teoretisk fysik (Nordita). Instituto de Astrofísica de Canarias, Spain.
    Mattsson, Lars
    Stockholms universitet, Nordiska institutet för teoretisk fysik (Nordita).
    Guergouri, Hichem
    Solano, Enrique
    Geier, Stefan
    Dom, Onyeuwaoma Nnaemeka
    Ward, Martin J.
    A glint in the eye: Photographic plate archive searches for non-terrestrial artefacts2022Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 194, s. 106-113Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, we present a simple strategy to identify Non-Terrestrial artefacts [NTAs; Haqq-Misra and Kopparapu (2012)] in or near geosynchronous Earth orbits (GEOs). We show that even the small pieces of reflective debris in orbit around the Earth can be identified through searches for multiple transients in old photographic plate material exposed before the launch of first human satellite in 1957. In order to separate between possible false point-like sources on photographic plates from real reflections, we present calculations to quantify the associated probabilities of alignments. We show that in an image with nine simultaneous transients at least four or five point sources along a line within a 10 * 10 arcmin(2) image box are a strong indicator of NTAs, corresponding to significance levels of 2.5 to 3.9 sigma. This given methodology can then be applied to set an upper limit to the prevalence of NTAs with reflective surfaces in geosynchronous orbits.

  • 44.
    Villarroel, Beatriz
    et al.
    Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden.;Inst Astrofis Canarias, Avda Via Lactea S-N, E-38205 San Cristobal la Laguna, Spain..
    Mattsson, Lars
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden..
    Guergouri, Hichem
    CERIST, Res Unit Sci Mediat, Sci Matter Div, Constantine, Algeria..
    Solano, Enrique
    Ctr Astrobiol CSIC INTA, Dept Astrofis, Box 78, Villanueva De La Canada E28691, Spain.;Spanish Virtual Observ, Granada, Spain..
    Geier, Stefan
    Inst Astrofis Canarias, Avda Via Lactea S-N, E-38205 San Cristobal la Laguna, Spain.;Gran Telescopio Canarias GRANTECAN, Cuesta San Jose S-N, La Palma 38712, Spain..
    Dom, Onyeuwaoma Nnaemeka
    Natl Space Res & Dev Agcy, Ctr Basic Space Sci, Enugu, Nigeria..
    Ward, Martin J.
    Univ Durham, Ctr Extragalact Astron, Dept Phys, South Rd, Durham DH1 3LE, England..
    A glint in the eye: Photographic plate archive searches for non-terrestrial artefacts2022Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 194, s. 106-113Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, we present a simple strategy to identify Non-Terrestrial artefacts [NTAs; Haqq-Misra and Kopparapu (2012)] in or near geosynchronous Earth orbits (GEOs). We show that even the small pieces of reflective debris in orbit around the Earth can be identified through searches for multiple transients in old photographic plate material exposed before the launch of first human satellite in 1957. In order to separate between possible false point-like sources on photographic plates from real reflections, we present calculations to quantify the associated probabilities of alignments. We show that in an image with nine "simultaneous transients" at least four or five point sources along a line within a 10 * 10 arcmin(2) image box are a strong indicator of NTAs, corresponding to significance levels of 2.5 to 3.9 sigma. This given methodology can then be applied to set an upper limit to the prevalence of NTAs with reflective surfaces in geosynchronous orbits.

  • 45.
    Vinterhav, Emil
    et al.
    Swedish Space Corporation.
    Karlsson, Thomas
    Swedish Space Corporation.
    Script based software for ground station and mission support operations for the Swedish small satellite Odin2007Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 61, nr 10, s. 912-922Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The small satellite Odin is a three-axis stabilised, high pointing accuracy, sub-millimetre, space observatory. One mean to attain as high efficiency as possible, which the Odin operations depend on, is the ability to quickly react to new input from the science users as well as platform and payload behaviour. Both the teams involved in the satellite operations are equipped with an easily accessible and modifiable set of software tools for monitoring telemetry and command generation. The software package is to a large extent based on scripts that have the advantage of being legible to the user and not only to the developer. Matlab scripts are used in most steps in the operations cycle, save the actual execution of commands onboard the spacecraft. Small and efficient teams of s/c operators and mission controllers together with easily accessible software, based on COTS components, facilitate in rapidly meeting new demands on spacecraft performance from the users.

  • 46.
    Wei, Jianzheng
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Mekanik. Harbin Inst Technol, Ctr Composite Mat & Struct, Harbin 150080, Heilongjiang, Peoples R China.
    Ma, Ruiqiang
    Harbin Inst Technol, Ctr Composite Mat & Struct, Harbin 150080, Heilongjiang, Peoples R China..
    Liu, Yufei
    China Acad Space Technol, Qian Xuesen Lab Space Technol, Beijing 100094, Peoples R China..
    Yu, Jianxin
    Harbin Inst Technol, Ctr Composite Mat & Struct, Harbin 150080, Heilongjiang, Peoples R China..
    Eriksson, Anders
    KTH, Skolan för teknikvetenskap (SCI), Mekanik.
    Tan, Huifeng
    Harbin Inst Technol, Ctr Composite Mat & Struct, Harbin 150080, Heilongjiang, Peoples R China..
    Modal analysis and identification of deployable membrane structures2018Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 152, s. 811-822Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The development of ultra-lightweight sails presents many challenges due to their large size and extreme flexibility. One of their key technologies is the design of deployable booms, in particular how to deploy and support the membrane structure. In this paper, a deployable sail with four triangular membranes supported by inflated booms enhanced by four self-supporting thin shells inside and Velcro outside is presented. The feasibility of the folding and unfolding processes is demonstrated, and their modal properties investigated. Firstly, the pressure variation and acceleration time history of a single boom during unfolding process were obtained by dynamic testing system, a finite element model of boom was proposed and structural natural frequencies by simulation were validated by experimental testing. Further, an 8.0 x 8.0 m(2) prototype was assembled and stowed in a Phi 700 mm by 300 mm container, and the structure was fully deployed with gas control. A finite element model of a combination of inflatable booms and triangular membranes was used to predict the structural overall bending modes. The effect of membrane wrinkling was simulated and controlled to improve membrane precision. This work validated the concept of deployable membrane structural design. The proposed finite element models were verified by experimental testing to be useful for membrane structure analysis.

  • 47.
    Yuan, Yunxia
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Rymd- och plasmafysik.
    Tibert, Gunnar
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Ivchenko, Mykola
    KTH, Skolan för elektro- och systemteknik (EES), Rymd- och plasmafysik.
    Precession and nutation of a free flying and axi-symmetric sphere2017Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Attitude motion of small suborbital probes is closely related to scientic measurements performed on these probes. Attitude dynamics of a free ying and axi-symmetric sphere is studied in this paper. The sphere is exposed to aerodynamic torques due to the deviation between the center of mass and the geometric center. For some system parameters and initial motion conditions, the attitude motion can be thought of as regular precession, as well as superposition of precession and nutation. These motion phenomena were modeled and some physical quantities were formulated to describe them. For regular precession to occur, the aerodynamic torque must be perpendicular to the total angular momentum, and the angular momentum of non-precession must be aligned with the axis of symmetry. For superposition motion, the aerodynamic torque must be perpendicular to the total angular momentum,and the angular momentum of non-precession must not be aligned with the axis of symmetry. Numerical simulations verify these analysis. Eventually, these models are used to analyze flight data.

  • 48.
    Yuan, Yunxia
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Rymd- och plasmafysik.
    Tibert, Gunnar
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Ivchenko, Nickolay
    KTH, Skolan för elektro- och systemteknik (EES), Rymd- och plasmafysik.
    Attitude reconstruction of suborbital small spacecrafts using a global optimization method2017Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Attitude motion of suborbital payloads is closely related to the quality of scientic measurements. In this paper, attitude reconstruction of suborbital payloads in terms of yaw-pitch-roll Euler angle is studied, according to measurements of magnetic fields from a magnetometer and angular velocities from a gyro sensor. To avoid complex dynamical modelling, the kinematic equations were used. The Euler angles were established by using an global optimization method. Moreover, the Euler angles were estimated by employing Unscented Kalman Filter (UKF) technique. The comparison of the optimized results to the ones from the UKF shows that the global optimization method provides higher accuracy than the UKF.

  • 49. Zhang, J.
    et al.
    Guo, H. -W
    Wu, J.
    Gao, G. -J
    Kou, Z. -M
    Eriksson, Anders
    KTH, Skolan för teknikvetenskap (SCI), Mekanik.
    Design and analysis of flexure revolute joint based on four-bar mechanism2018Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 151, s. 420-431Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to avoid the stress concentration and increase rotational angle of a flexure joint, the method of partial separation of storage elements in the motion transmission elements is proposed. A type of flexure revolute joint with large rotational angle is designed based on the block approach. By setting a 4-bar mechanism as the intermediate block which connects the outer ring and the inner ring of the revolute joint, and replacing the rigid bar by a flexible beam, large rotational angles of the joint can be achieved. The basic size of the joint is designed by setting the initial and the constraint condition of the 4-bar mechanism. Then, influence analyses of the size of the linkage joint and large flexible beam on the stress, the torque, and the torsional stiffness are conducted by using nonlinear static analysis method. Based on the requirements for torque and rotational stiffness, the size of the flexure revolute joint is defined. Experiments on the joint, which can rotate 90° are conducted. 

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