Showing papers in "Acta Astronautica in 1996"

TL;DR: In this paper, the antenna surface is divided into a series of panels, which fold by wrapping around a central hub, and all connections between the panels are made by revolute joints.

TL;DR: The International Space Station (ISS) as discussed by the authors represents the largest scientific and technological cooperative program in history, drawing on the resources of thirteen nations, including the Russian Space Agency, numerous nations of the European Space Agency (ESA), and the space agencies of Canada (CSA), Japan (NASDA) and the United States Space Agency(NASA).

TL;DR: In this article, the authors quantify the amount of dust coverage expected and the amount lost, using available data on Martian conditions, and find that the degradation of array performance could be between 1 and 50% over a 30-day mission, and between 22 and 89% over two-year mission.

TL;DR: A concept under development at L'Garde, Inc., for a large, inflatable-deployable antenna represents an excellent example of this new type of structure that has great potential for satisfying stringent user requirements.

TL;DR: In this paper, a solar sail spacecraft of about 240kg total mass is proposed to deliver a limited but highly valuable science payload to a sun-synchronous Mercury orbit in 3 1 2 years.

TL;DR: In this paper, the first time in practice of bistatic radiolocation of the Earth from space reflected signal in the radioshadow zone was observed and the analysis of experimental results verified the developed radiophysical model with the value of sea water conductivity σ = 7.0 mo/m and absorption coefficient due to atmospheric oxygen χ = 0.0096±0.

TL;DR: In this article, the problem of optimal low-thrust rendezvous using continuous constant acceleration is presented based on the use of the non-singular equinoctial orbit elements.

TL;DR: In this article, optimal trajectories are optimized from the point of view of performance and control margin, and a trade-off between performance and margin is generated from a tradeoff between precision requirements of AOT trajectories and the need for coping with various sources of dispersion effects.

TL;DR: In this article, the minimum energy trajectories to transfer a spacecraft between the five Lagrangian points and Earth were considered. And the planar circular restricted three-body problem in two dimensions was used as the model for the Earth-Moon system, and Lemaitre regularization was used to avoid singularities.

TL;DR: In this paper, an extended Kalman-type filter is used to deduce a minimum error estimate of the spacecraft ephemeris by utilizing the knowledge of system and measurement dynamics, assumed statistics of system noises and measurement errors, and initial condition information.

TL;DR: In this paper, an ion thruster is used for solar electric propulsion (SEP) in a sample and return mission to near Earth asteroid Nereus (4660) via an electric propulsion.

TL;DR: In this article, the authors describe a "maturing" class of attitude sensors used to determine spacecraft attitude with respect to the celestial sphere and describe the principles of operation and processes by which these star field trackers recognize and track a desired star field.

TL;DR: In this paper, a photon solar-sail spacecraft with a lightness number in the range [ 1 2 −1 ] (all-metallic sail) is analyzed and a class of heliocentric trajectories, characterized by orbital angularmomentum reversal, delivering a considerable cruise speed (10-20 AU/yr) and allowing a sailcraft to access any celestial latitude [ −π 2, +π 2 ], depending primarily on the perihelion distance.

TL;DR: Simultaneous attitude and vibration control of a space platform using the LQG/LTR approach with the linearized equations obtained through a novel finite difference procedure is studied in this article, where the control strategy is quite effective in damping a wide variety of disturbances including the Shuttle docking, manipulator maneuvers, solar array tracking and initial displacements imparted to the system as well as its subassemblies.

TL;DR: It was shown that the BLSS with higher plants and incineration of wastes becomes the best when the exploitation period is more than 1 yr and the dependence of higher plants' LSS structure on operation time was found.

TL;DR: The Advanced Stellar Compass (ASC) as mentioned in this paper is a fully autonomous miniature star tracker, which is capable of both solving the lost in space problem and determining the attitude with arcseconds precision.

TL;DR: In this article, the authors present a survey of dynamics modelling issues and control schemes for large robotic space manipulators, including the Space Station RMS, the European Robotic Arm, and the Japanese Experiment Module RMS.

TL;DR: In this article, a transpose-based CMG-based attitude control of a spacecraft is proposed. But, it does not require calculating the pseudo-inverse of the CMG Jacobian matrix, and the proposed method provides viable rates for the CMGs even when the gimbals pass through a singular configuration.

TL;DR: In this article, the authors survey the radiative properties of thin, cold clouds composed of asymmetric ice particles and discuss multispectral cirrus cloud observations and review the latest satellite cloud climatologies.

TL;DR: In this article, the authors propose an approach for low-cost autonomous orbit maintenance for Earth satellites in specialized orbits, such as a repeating ground track, or in formations, which typically requires less software, and less complex software, than does orbit control from the ground.

TL;DR: In this article, the authors introduce a new class of nano-satellites, which can be used to build a very small satellite with capabilities comparable to present microsatellite, but with the possibility of cheap mass production of such nanosatellites.

TL;DR: In this paper, the SGP4 model is used for low-Earth orbiting satellites that is widely used for the propagation of NORAD twoline elements, which simplifies the operations concept and reduces mission costs through the extensive use of existing low-cost mission support software.

TL;DR: In this paper, the influence of body forces on polymerization at three qualitatively different gravity levels: microgravity, terrestrial and high gravity conditoins was reviewed and the photopolymerization of polyacrylamide gel (PAG) was found to develop as a frontal process in stagnant liquid.

TL;DR: Successful application of NASA implantable biosensor and biotelemetry technologies should accelerate the advancement of this and other modern medical procedures while furthering the exploration of life in space.

TL;DR: The DLR-TUBSAT project as discussed by the authors is a joint project of the DLR Institute of Space Sensor Technology and the Institute of Aeronautics and Astronautics at the Technical University of Berlin.

TL;DR: In this article, a non-equilibrium phase transition in the presence of heat, mass, momentum and energy fluxes through the phase interface is investigated, and a self-similar solution of the unsteady problem is obtained providing the possibility to follow temperature and concentration of species profiles' evolution in time.

TL;DR: A review of analogue work environments is carried out to make up for the paucity of space research found in the area of human performance in long-duration spaceflight and industrial process control and nuclear submarines come out as the closest match on the technical dimension.

TL;DR: This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33,X-34 flight systems and associated technology programs and examines how these technologies and flight systems address the technical and operability challenges of SSTO whose solutions are necessary to reduce costs.

TL;DR: In this paper, a framework for determining whether power from space is needed for the Earth and if the approach suggested by its advocates is sound is established and a framework is established for determining this need and soundness of approach.

TL;DR: In this article, a synchronously deployable truss structure forming a curved reflector surface has been developed to ensure reliable deployment, which is based on a non-linear finite element method, rather than on multi-body dynamics.