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  • 1.
    Bazzocchi, Michael C.F.
    et al.
    Institute for Aerospace Studies, University of Toronto.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Comparative analysis of redirection methods for asteroid resource exploitation2016In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 120, 1-19 p.Article in journal (Refereed)
    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.

  • 2. Berg, H.E
    et al.
    Tesch, P.A
    Force and power characteristics of a resistive exercise device for use in space1998In: Acta Astronautica, ISSN 0094-5765, Vol. 42, 219-230 p.Article in journal (Refereed)
  • 3. 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 bed2011In: Acta Astronautica, ISSN 0094-5765, Vol. 68, no 7, 862-872 p.Article in journal (Refereed)
    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.

  • 4.
    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 exploration2008In: Acta Astronautica, ISSN 0094-5765, Vol. 63, no 5-6, 618-631 p.Article in journal (Refereed)
    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.

  • 5.
    Bruhn, Fredrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Kratz, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Warell, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics.
    Lagerkvist, Claes-Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics.
    Kaznov, Viktor
    Jones, Jack A
    Stenmark, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    A Preliminary Design for a Spherical Inflatable Microrover for Planetary Exploration2008In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 63, no 5-6, 618-631 p.Article in journal (Refereed)
    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.

  • 6.
    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 University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    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 moons2017In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 139, 545-563 p.Article in journal (Refereed)
    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.

  • 7. Delpech, M
    et al.
    Malbet, F
    Karlsson, Thomas
    Larsson, Robin
    KTH, School of Electrical Engineering (EES), Signal Processing. OHB Sweden.
    Léger, A
    Jorgensen, J
    Flight demonstration of formation flying capabilities for future missions (NEAT Pathfinder)2014In: Acta Astronautica, ISSN 0094-5765, Vol. 105, no 1, 82-94 p.Article in journal (Refereed)
    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.

  • 8.
    Felicetti, Leonard
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    A multi-spacecraft formation approach to space debris surveillance2016In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 127, 491-504 p.Article in journal (Refereed)
    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.

  • 9.
    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' stages2016In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 119, 118-130 p.Article in journal (Refereed)
    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

  • 10.
    Felicetti, Leonard
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    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 forces2016In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 123, 455-469 p.Article in journal (Refereed)
    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.

  • 11.
    Jonsson, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Sundqvist, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Nguyen, Hugo
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Berglund, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Ogden, Sam
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Palmer, Kristoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Smedfors, Katarina
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Johansson, Linda
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Thornell, Greger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Instrumentation and vehicle platform of a miniaturized submersible for exploration of terrestrial and extraterrestrial aqueous environments2012In: Acta Astronautica, ISSN 0094-5765, Vol. 79, 203-211 p.Article in journal (Refereed)
    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.

  • 12.
    Kozynchenko, Alexander I
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Predictive guidance algorithms for maximal downrange maneuvrability with application to low-lift re-entry2009In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 64, no 7-8, 770-777 p.Article in journal (Refereed)
    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.

  • 13.
    Liberman, M. A.
    et al.
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Stockholm univ.
    Ivanov, M. F.
    Kiverin, A. D.
    Radiation heat transfer in particle-laden gaseous flame: Flame acceleration and triggering detonation2015In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 115, 82-93 p.Article in journal (Refereed)
    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.

  • 14.
    Liberman, M. A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Ivanov, M. F.
    Kiverin, A. D.
    Kuznetsov, M. S.
    Chukalovsky, A. A.
    Rakhimova, T. V.
    Deflagration-to-detonation transition in highly reactive combustible mixtures2010In: Acta Astronautica, ISSN 0094-5765, Vol. 67, no 7-8, 688-701 p.Article in journal (Refereed)
    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.

  • 15.
    Liberman, Michael A.
    et al.
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Ivanov, M. F.
    Kiverin, A. D.
    Radiation heat transfer in particle-laden gaseous flame: Flame acceleration and triggering detonation2015In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 115, 82-93 p.Article in journal (Refereed)
    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.

  • 16.
    Mao, Huina
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Sinn, Thomas
    Vasile, Massimiliano
    Tibert, Gunnar
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Post-launch analysis of the deployment dynamics of a space web sounding rocket experiment2016In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 127, 345-358 p.Article in journal (Refereed)
    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.

  • 17. Mege, Daniel
    et al.
    Gurgurewicz, Joanna
    Grygorczuk, Jerzy
    Wisniewski, Lukasz
    Thornell, Greger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    The Highland Terrain Hopper (HOPTER): Concept and usecases of a new locomotion system for the exploration of lowgravity Solar System bodies2016In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 121, 200-220 p.Article in journal (Refereed)
    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.

  • 18.
    Muralidharan, Vijay
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Concurrent rendezvous control of underactuated spacecraft2017In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 138, 28-42 p.Article in journal (Refereed)
    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.

  • 19.
    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 University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    The Highland Terrain Hopper (HOPTER): Concept and use cases of a new locomotion system for the exploration of low gravity Solar System bodies2016In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 121, 200-220 p.Article in journal (Refereed)
    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.

  • 20. Straube, Ulrich
    et al.
    Berger, Thomas
    Reitz, Guenther
    Facius, Rainer
    Fuglesang, Christer
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Reiter, Thomas
    Damann, Volker
    Tognini, Michel
    Operational radiation protection for astronauts and cosmonauts and correlated activities of ESA Medical Operations2010In: Acta Astronautica, ISSN 0094-5765, Vol. 66, no 7-8, 963-973 p.Article, review/survey (Refereed)
    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.

  • 21.
    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 Odin2007In: Acta Astronautica, ISSN 0094-5765, Vol. 61, no 10, 912-922 p.Article in journal (Refereed)
    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.

  • 22.
    Yuan, Yunxia
    et al.
    KTH, School of Electrical Engineering (EES), Space and Plasma Physics.
    Tibert, Gunnar
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Ivchenko, Mykola
    KTH, School of Electrical Engineering (EES), Space and Plasma Physics.
    Precession and nutation of a free flying and axi-symmetric sphere2017In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030Article in journal (Other academic)
    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.

  • 23.
    Yuan, Yunxia
    et al.
    KTH, School of Electrical Engineering (EES), Space and Plasma Physics.
    Tibert, Gunnar
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Ivchenko, Nickolay
    KTH, School of Electrical Engineering (EES), Space and Plasma Physics.
    Attitude reconstruction of suborbital small spacecrafts using a global optimization method2017In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030Article in journal (Other academic)
    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.

1 - 23 of 23
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