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Dongping Jin - One of the best experts on this subject based on the ideXlab platform.

  • Chaos in a tethered satellite system induced by Atmospheric Drag and Earth’s oblateness
    Nonlinear Dynamics, 2020
    Co-Authors: Dongping Jin
    Abstract:

    This paper describes the chaos behavior of an in-plane tethered satellite system induced by Atmospheric Drag and the Earth’s oblateness. A commonly used model, the dumbbell model, for tethered satellite systems is employed in this study. After taking the Atmospheric Drag and the Earth’s oblateness into account, the complicated dynamics of chaotic features are observed in the pitch motion of the dumbbell model. Afterward, the existence of the chaos is computed by transversal heteroclinic orbits, and accordingly, the parameter domain for the occurrence of chaos is obtained by the Melnikov function. Furthermore, a tether length control based on a sliding-mode controller is proposed to suppress the chaotic motion. Finally, the numerical simulations in this paper demonstrate the occurrence of the chaotic phenomenon and its control performance.

  • chaos in a tethered satellite system induced by Atmospheric Drag and earth s oblateness
    Nonlinear Dynamics, 2020
    Co-Authors: Dongping Jin
    Abstract:

    This paper describes the chaos behavior of an in-plane tethered satellite system induced by Atmospheric Drag and the Earth’s oblateness. A commonly used model, the dumbbell model, for tethered satellite systems is employed in this study. After taking the Atmospheric Drag and the Earth’s oblateness into account, the complicated dynamics of chaotic features are observed in the pitch motion of the dumbbell model. Afterward, the existence of the chaos is computed by transversal heteroclinic orbits, and accordingly, the parameter domain for the occurrence of chaos is obtained by the Melnikov function. Furthermore, a tether length control based on a sliding-mode controller is proposed to suppress the chaotic motion. Finally, the numerical simulations in this paper demonstrate the occurrence of the chaotic phenomenon and its control performance.

Colin R Mcinnes - One of the best experts on this subject based on the ideXlab platform.

  • Needs assessment of gossamer structures in communications platform end-of-life disposal
    AIAA Guidance Navigation and Control (GNC) Conference, 2013
    Co-Authors: Malcolm Macdonald, Colin R Mcinnes, Charlotte Bewick
    Abstract:

    The use of a gossamer structure is considered in application to end-of-life disposal of communications platforms. A wide-ranging survey of end-of-life disposal techniques and strategies is presented for comparison against a gossamer structure prior to a down-selection of viable competing techniques; solar sailing, high and low-thrust propulsion, and electrodynamic tethers. A parametric comparison of the down-selection competing techniques is presented where it was found that exploiting solar radiation pressure on the gossamer structure was of limited value. In general terms, it was found that if a spacecraft propulsion system remains functioning at the end-of-life then this will likely provide the most efficient means of re-orbiting, especially when the propulsion system is only used to lower the orbit to a point where Atmospheric Drag will cause the orbit to decay within the required timeframe. Atmospheric Drag augmentation was found to be of most benefit for end-of-life disposal when an entirely passive means is required, allowing the device to act as a ‘fail-safe’, which if the spacecraft suffers a catastrophic failure would activate. The use of an Atmospheric Drag augmentation system is applicable to only low and medium mass spacecraft, or spacecraft that are unlikely to survive Atmospheric re-entry, hence minimizing risk to human life.

  • Orbit evolution, maintenance and disposal of SpaceChip swarms through electro-chromic control
    Acta Astronautica, 2013
    Co-Authors: Camilla Colombo, Charlotte Lücking, Colin R Mcinnes
    Abstract:

    The combined effect of solar radiation pressure, Earth oblateness and Atmospheric Drag on the orbital dynamics of satellites-on-a-chip (SpaceChips) is investigated for future swarm mission concepts. The natural evolution of the swarm is exploited to perform spatially distributed measurements of the upper layers of the atmosphere. The energy gain from asymmetric solar radiation pressure can be used to balance the energy dissipation from Atmospheric Drag. An algorithm for long-term orbit control is then designed, based on changing the reflectivity coefficient of the SpaceChips. The subsequent modulation of the solar radiation pressure allows stabilisation of the swarm in the orbital element phase space. It is shown that the orbit lifetime for such devices can be extended through the interaction of solar radiation pressure and Atmospheric Drag and indeed selected and the end-of-life re-entry of the swarm can be ensured, by exploiting Atmospheric Drag.

  • Orbit design for future SpaceChip swarm missions in a planetary atmosphere
    Acta Astronautica, 2012
    Co-Authors: Camilla Colombo, Colin R Mcinnes
    Abstract:

    The effect of solar radiation pressure and Atmospheric Drag on the orbital dynamics of satellites-on-a-chip (SpaceChips) is exploited to design equatorial long-lived orbits about the oblate Earth. The orbit energy gain due to asymmetric solar radiation pressure, considering the Earth's shadow, is used to balance the energy loss due to Atmospheric Drag. Future missions for a swarm of SpaceChips are proposed, where a number of small devices are released from a conventional spacecraft to perform spatially distributed measurements of the conditions in the ionosphere and exosphere. It is shown that the orbit lifetime can be extended and indeed selected through solar radiation pressure and the end-of-life re-entry of the swarm can be ensured, by exploiting Atmospheric Drag.

  • orbital dynamics of smart dust devices with solar radiation pressure and Drag
    Journal of Guidance Control and Dynamics, 2011
    Co-Authors: Camilla Colombo, Colin R Mcinnes
    Abstract:

    This paper investigates how perturbations due to asymmetric solar radiation pressure, in the presence of Earth shadow, and Atmospheric Drag can be balanced to obtain long-lived Earth centred orbits for swarms of micro-scale 'smart dust' devices, without the use of active control. The secular variation of Keplerian elements is expressed analytically through an averaging technique. Families of solutions are then identified where Sun-synchronous apse-line precession is achieved passively to maintain asymmetric solar radiation pressure. The long-term orbit evolution is characterized by librational motion, progressively decaying due to the non-conservative effect of Atmospheric Drag. Long-lived orbits can then be designed through the interaction of energy gain from asymmetric solar radiation pressure and energy dissipation due to Drag. In this way, the usual short Drag lifetime of such high area-to-mass spacecraft can be greatly extended (and indeed selected). In addition, the effect of Atmospheric Drag can be exploited to ensure the rapid end-of-life decay of such devices, thus preventing long-lived orbit debris.

  • Orbit evolution, maintenance and disposal of SpaceChip swarms
    2010
    Co-Authors: Camilla Colombo, Charlotte Lücking, Colin R Mcinnes
    Abstract:

    The combined effect of solar radiation pressure and Atmospheric Drag is investigated for future mission concepts for swarms of satellites-on-a-chip (SpaceChips). The natural evolution of the swarm is exploited to perform spatially distributed measurements of the upper layers of the atmosphere. The energy gain from asymmetric solar radiation pressure can be used to balance the energy dissipation from Atmospheric Drag. An algorithm for long-term orbit control is then designed, based on changing the reflectivity coefficient of the SpaceChips. The subsequent modulation of the solar radiation pressure allows stabilisation of the swarm in the orbital element phase space. It is shown that the normally short orbit lifetime for such devices can be extended through the interaction of solar radiation pressure and Atmospheric Drag and indeed selected and the end-of-life re-entry of the swarm can be ensured, by exploiting Atmospheric Drag.

Jean-charles Marty - One of the best experts on this subject based on the ideXlab platform.

  • First ever in situ observations of Venus' polar upper atmosphere density using the tracking data of the Venus Express Atmospheric Drag Experiment (VExADE)
    Icarus, 2012
    Co-Authors: Pascal Rosenblatt, Sean Bruinsma, Ingo Müller-wodarg, Bernd Häusler, Håkan Svedhem, Jean-charles Marty
    Abstract:

    On its highly elliptical 24. h orbit around Venus, the Venus Express (VEX) spacecraft briefly reaches a periapsis altitude of nominally 250. km. Recently, however, dedicated and intense radio tracking campaigns have taken place in August 2008, October 2009, February and April 2010, for which the periapsis altitude was lowered to the 186-176. km altitude range in order to be able to probe the upper atmosphere of Venus above the North Pole for the first time ever in situ. As the spacecraft experiences Atmospheric Drag, its trajectory is measurably perturbed during the periapsis pass, allowing us to infer total Atmospheric mass density at the periapsis altitude. A Precise Orbit Determination (POD) of the VEX motion is performed through an iterative least-squares fitting process to the Doppler tracking data, acquired by the VEX radioscience experiment (VeRa). The Drag acceleration is modelled using an initial Atmospheric density model (VTS3 model, Hedin, A.E., Niemann, H.B., Kasprzak, W.T., Seiff, A. [1983]. J. Geophys. Res. 88, 73-83). A scale factor of the Drag acceleration is estimated for each periapsis pass, which scales Hedin's density model in order to best fit the radio tracking data. Reliable density scale factors have been obtained for 10 passes mainly from the second (October 2009) and third (April 2010) VExADE campaigns, which indicate a lower density by a factor of about 1.8 than Hedin's model predicts. These first ever in situ polar density measurements at solar minimum have allowed us to construct a diffusive equilibrium density model for Venus' thermosphere, constrained in the lower thermosphere primarily by SPICAV-SOIR measurements and above 175. km by the VExADE Drag measurements (Muller-Wodarg et al., in preparation). The preliminary results of the VExADE campaigns show that it is possible to obtain with the POD technique reliable estimates of Venus' upper atmosphere densities at an altitude of around 175. km. Future VExADE campaigns will benefit from the planned further lowering of VEX pericenter altitude to below 170. km. © 2011 Elsevier Inc.

Ta-kang Yeh - One of the best experts on this subject based on the ideXlab platform.

  • Analytical solution of a satellite orbit disturbed by Atmospheric Drag
    Monthly Notices of the Royal Astronomical Society, 2010
    Co-Authors: Xu Tianhe, Wu Chen, Ta-kang Yeh
    Abstract:

    In this paper, we derive the analytical solution of a satellite orbit disturbed by Atmospheric Drag. The disturbance force vector is first transformed and rotated to the orbital frame so that it can be used in the simplified Gaussian equations of satellite motion. Then, the force vector is expanded to triangular functions of the Keplerian angular elements and the disturbances are separated into three parts: short-periodic terms with triangular functions of M, long-periodic terms with triangular functions of (ω, i) and secular terms [non-periodic functions of (a, e)] with a program using mathematical symbolic operation software. The integrations are then carried out with respect to M, (ω, i) and t, respectively, to obtain the analytical solutions of satellite orbits disturbed by Atmospheric Drag. Some interesting conclusions are obtained theoretically. The Atmospheric disturbance force is not a function of Ω. The semimajor axis a of the orbital ellipse is reduced in a constant and strong manner by the air disturbance; the shape of the ellipse (eccentricity e) changes towards a more circular orbit in a linear and weak manner. The right ascension of the ascending node Ω and the mean anomaly M are influenced by the disturbance only short periodically.

Stefan Schindler - One of the best experts on this subject based on the ideXlab platform.

  • Atmospheric Drag, Occultation 'N' Ionospheric Scintillation (ADONIS) mission proposal
    Journal of Space Weather and Space Climate, 2015
    Co-Authors: Sebastian Hettrich, Nikolaos Perakis, Martina Edl, Jaroslav Urbár, Melinda Dósa, Francesco Gini, Yann Kempf, Jȩdrzej Górski, Owen Roberts, Stefan Schindler
    Abstract:

    The Atmospheric Drag, Occultation 'N' Ionospheric Scintillation mission (ADONIS) studies the dynamics of the terrestrial thermosphere and ionosphere in dependency of solar events over a full solar cycle in Low Earth Orbit (LEO). The objectives are to investigate satellite Drag with in-situ measurements and the ionospheric electron density profiles with radio occultation and scintillation measurements. A constellation of two satellites provides the possibility to gain near real-time data (NRT) about ionospheric conditions over the Arctic region where current coverage is insufficient. The mission shall also provide global high-resolution data to improve assimilative ionospheric models. The low-cost constellation can be launched using a single Vega rocket and most of the instruments are already space-proven allowing for rapid development and good reliability. From July 16 to 25, 2013, the Alpbach Summer School 2013 was organised by the Austrian Research Promotion Agency (FFG), the European Space Agency (ESA), the International Space Science Institute (ISSI) and the association of Austrian space industries Austrospace in Alpbach, Austria. During the workshop, four teams of 15 students each independently developed four different space mission proposals on the topic of "Space Weather: Science, Missions and Systems", supported by a team of tutors. The present work is based on the mission proposal that resulted from one of these teams' efforts.

  • Atmospheric Drag, Occultation ‘N’ Ionospheric Scintillation (ADONIS) mission proposal
    Journal of Space Weather and Space Climate, 2015
    Co-Authors: Sebastian Hettrich, Yann Pfau-kempf, Nikolaos Perakis, Jedrzej Górski, Martina Edl, Jaroslav Urbár, Melinda Dósa, Francesco Gini, Owen W. Roberts, Stefan Schindler
    Abstract:

    The Atmospheric Drag, Occultation 'N' Ionospheric Scintillation mission (ADONIS) studies the dynamics of the terrestrial thermosphere and ionosphere in dependency of solar events over a full solar cycle in Low Earth Orbit (LEO). The objectives are to investigate satellite Drag with in-situ measurements and the ionospheric electron density profiles with radio occultation and scintillation measurements. A constellation of two satellites provides the possibility to gain near real-time data (NRT) about ionospheric conditions over the Arctic region where current coverage is insufficient. The mission shall also provide global highresolution data to improve assimilative ionospheric models. The low-cost constellation can be launched using a single Vega rocket and most of the instruments are already space-proven allowing for rapid development and good reliability.