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Nasa - One of the best experts on this subject based on the ideXlab platform.
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Spacecraft Design project: High temperature superconducting infrared imaging satellite
2019Co-Authors: NasaAbstract:The High Temperature Superconductor Infrared Imaging Satellite (HTSCIRIS) is Designed to perform the space based infrared imaging and surveillance mission. The Design of the satellite follows the black box approach. The payload is a stand alone unit, with the Spacecraft bus Designed to meet the requirements of the payload as listed in the statement of work. Specifications influencing the Design of the Spacecraft bus were originated by the Naval Research Lab. A description of the following systems is included: Spacecraft configuration, orbital dynamics, radio frequency communication subsystem, electrical power system, propulsion, attitude control system, thermal control, and structural Design. The issues of testing and cost analysis are also addressed. This Design project was part of the course Advanced Spacecraft Design taught at the Naval Postgraduate School.
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Thermionic Spacecraft Design Study
2018Co-Authors: NasaAbstract:This report presents the results of a Design study of nuclear-electric propelled unmanned Spacecraft. The electric power source is in-core thermionic reactors based on either the internally (flashlight) or externally fueled diode concept. The study guidelines and approach are defined. The characteristics of the candidate launch vehicles, thrust subsystem, and communications subsystem are presented. The definition of two Spacecraft/powerplant configurations are presented which deliver 240 kWe net to the thruster array. This definition, presented for both the flashlight and externally fueled reactors includes the key items of Spacecraft arrangement and a detailed weight breakdown. Power conditioning, heat rejection subsystem, shielding, and Spacecraft structure are detailed. The results show about a 30 percent weight advantage for the Spacecraft based on the externally fueled reactor. This is primarily due to a 120 vdc power output from the externally fueled reactor, as compared to a 15 vdc power output from the flashlight reactor. Weight reduction by improved technology could further reduce the weight by 5 to 15 percent.
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Thermionic Spacecraft Design study, 120 kw nuclear electric propulsion system. Volume 2: External fuel reactor Spacecraft Design
2013Co-Authors: NasaAbstract:Design and development of electrically propelled Spacecraft based on external-fuel reactor concepts for thermionic reactors - Vol. 2
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Tracking and data relay satellite system configuration and tradeoff study. Volume 5: TDRS Spacecraft Design, part 1
2013Co-Authors: NasaAbstract:A dual spin stabilized TDR Spacecraft Design is presented for low data rate (LDR) and medium data rate (MDR) user Spacecraft telecommunication relay service. The relay satellite provides command and data return channels for unmanned users together with duplex voice and data communication channels for manned user Spacecraft. TDRS/ground links are in the Ku band. Command links are provided at UHF for LDR users and S band for MDR users. Voice communication channels are provided at UHF/VHF for LDR users and at S band for MDR users. The Spacecraft is Designed for launch on the Delta 2914 with system deployment planned for 1978. This volume contains a description of the overall TDR Spacecraft configuration, a detailed description of the Spacecraft subsystems, a reliability analysis, and a product effectiveness plan.
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Comet explorer Spacecraft Design project
2004Co-Authors: NasaAbstract:The small, chemically primitive objects of the solar system, comets and asteroids, are one of the most important frontiers remaining for future planetary exploration. So stated the Solar System Exploration Committee of the NASA Advisory Council in its 1986 report 'Planetary Exploration Through the Year 2000.' The Halley's comet flyby missions completed last spring raised more questions than were answered about the nature of comets. The next mission to a comet must be able to explore some of these questions. In the late 1990's, a Spacecraft might be built to explore the hazardous area surrounding a comet nucleus. Rigorous pointing requirements for remote sensing instruments will place a considerable burden on their attendant control systems. To meet these requirements we have pursued the initial Design and analysis of a multi-bodied comet explorer Spacecraft. Sized so as to be built on-orbit after the space station is operational, the Spacecraft is comprised of Orbit Replaceable Unit (ORU) subsystems, packaged into two major components: a three-axis controlled instrument platform and a spinning, detached comet dust shield. Such a configuration decouples the dynamics of dust impaction from the stringent pointing out requirements of the imaging experiments. At the same time, it offers an abundance of simple analysis problems that may be carried out by undergraduates. These problems include the following: Selection of subsystem components, sizing trade studies, investigation of three-axis and simple spin dynamics, Design of simple control systems, orbit determination, and intercept trajectory generation. Additionally, such topics as proposal writing project management, human interfacing, and costing have been covered. A new approach to Design teaching has been taken, whereby students will 'learn by teaching.' They are asked to decompose trade options into a set of 'if-then' rules, which then 'instruct' the Mechanically Intelligent Designer (MIND) expert Design system in how to carry out a Design.
Mirko Trisolini - One of the best experts on this subject based on the ideXlab platform.
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Spacecraft Design optimisation for demise and survivability
Aerospace Science and Technology, 2018Co-Authors: Mirko Trisolini, Hugh G Lewis, Camilla ColomboAbstract:Abstract Among the mitigation measures introduced to cope with the space debris issue there is the de-orbiting of decommissioned satellites. Guidelines for re-entering objects call for a ground casualty risk no higher than 10−4. To comply with this requirement, satellites can be Designed through a Design-for-demise philosophy. Still, a Spacecraft Designed to demise through the atmosphere has to survive the debris-populated space environment for many years. The demisability and the survivability of a satellite can both be influenced by a set of common Design choices such as the material selection, the geometry definition, and the position of the components inside the Spacecraft. Within this context, two models have been developed to analyse the demise and the survivability of satellites. Given the competing nature of the demisability and the survivability requirements, a multi-objective optimisation framework was developed, with the aim to identify trade-off solutions for the preliminary Design of satellites. As the problem is nonlinear and involves the combination of continuous and discrete variables, classical derivative based approaches are unsuited and a genetic algorithm was selected instead. The genetic algorithm uses the developed demisability and survivability criteria as the fitness functions of the multi-objective algorithm. The paper presents a test case, which considers the preliminary optimisation of tanks in terms of material, geometry, location, and number of tanks for a representative Earth observation mission. The configuration of the external structure of the Spacecraft is fixed. Tanks were selected because they are sensitive to both Design requirements: they represent critical components in the demise process and impact damage can cause the loss of the mission because of leaking and ruptures. The results present the possible trade off solutions, constituting the Pareto front obtained from the multi-objective optimisation.
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Spacecraft Design optimisation for demise and survivability
Aerospace Science and Technology, 2018Co-Authors: Mirko Trisolini, Hugh G Lewis, Camilla ColomboAbstract:Abstract Among the mitigation measures introduced to cope with the space debris issue there is the de-orbiting of decommissioned satellites. Guidelines for re-entering objects call for a ground casualty risk no higher than 10−4. To comply with this requirement, satellites can be Designed through a Design-for-demise philosophy. Still, a Spacecraft Designed to demise through the atmosphere has to survive the debris-populated space environment for many years. The demisability and the survivability of a satellite can both be influenced by a set of common Design choices such as the material selection, the geometry definition, and the position of the components inside the Spacecraft. Within this context, two models have been developed to analyse the demise and the survivability of satellites. Given the competing nature of the demisability and the survivability requirements, a multi-objective optimisation framework was developed, with the aim to identify trade-off solutions for the preliminary Design of satellites. As the problem is nonlinear and involves the combination of continuous and discrete variables, classical derivative based approaches are unsuited and a genetic algorithm was selected instead. The genetic algorithm uses the developed demisability and survivability criteria as the fitness functions of the multi-objective algorithm. The paper presents a test case, which considers the preliminary optimisation of tanks in terms of material, geometry, location, and number of tanks for a representative Earth observation mission. The configuration of the external structure of the Spacecraft is fixed. Tanks were selected because they are sensitive to both Design requirements: they represent critical components in the demise process and impact damage can cause the loss of the mission because of leaking and ruptures. The results present the possible trade off solutions, constituting the Pareto front obtained from the multi-objective optimisation.
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Dataset for Demise and Survivability Criteria for Spacecraft Design Optimization
2017Co-Authors: Mirko TrisoliniAbstract:Dataset supporting: Trisolini, M., Colombo, C., and Lewis, H. (2016). Demise and Survivability Criteria for Spacecraft Design Optimization. The Journal of Space Safety Engineering, 3(2), 83–93. DOI: 10.1016/S2468-8967(16)30023-4Trisolini, M., Colombo, C., and Lewis, H. (2017). Demise and survivability criteria for Spacecraft Design optimisation. In Proceedings of the 8th International Association for Advancement of Space Safety Conference (2016 IAASS).Funded by EPSRC (DTA - University of Southampton - EP/K503150/1).
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Dataset for Survivability and demise criteria for sustainable Spacecraft Design
2017Co-Authors: Mirko TrisoliniAbstract:The archive contains the data files used to generate the plots and maps for the article presented at the 2015 International Astronautical Congress.Trisolini, M., Colombo, C., and Lewis, H. (2015). Survivability and demise criteria for sustainable Spacecraft Design. In Proceedings of the 66th International Astronautical Congress. (pp. 2505-2523). Elsevier B.V.
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Dataset for Spacecraft Design optimisation for demise and survivability
2017Co-Authors: Mirko TrisoliniAbstract:The archive contains the results of the multi-objective optimisation used to generate the Pareto fronts in the article. More data than the one presented is actually in the archive.Trisolini, M., Lewis, H., and Colombo, C. (2017). Spacecraft Design optimisation for demise and survivability. In Proceedings of the 67th International Astronautical Congress (2016 IAC).Funded by EPSRC (DTA - University of Southampton - EP/K503150/1).
Kristina N. Safdie - One of the best experts on this subject based on the ideXlab platform.
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Lunar Reconnaissance Orbiter Mission and Spacecraft Design
Space Science Reviews, 2010Co-Authors: C. R. Tooley, Martin B. Houghton, Richard S. Saylor, Cathy Peddie, David F. Everett, Charles L. Baker, Kristina N. SafdieAbstract:Launched June 18, 2009, with its primary mission scheduled to end September 2010, NASA’s Lunar Reconnaissance Orbiter will be the first observatory ever to spend an entire year orbiting and observing the Moon at a low altitude of just 50 km. The Spacecraft carries a wide variety of scientific instruments and will provide an extraordinary opportunity to study the lunar landscape at resolutions and over time scales never achieved before. This paper is intended as a companion to the series of papers released simultaneously in this journal detailing LRO’s instruments and their planned measurements. The paper describes the Design and key performance drivers of the LRO Spacecraft and overall mission Design. It presents a comprehensive description of the operation of the various systems that comprise the Spacecraft and illustrates how these systems enable achievement of the mission requirements.
Dava J. Newman - One of the best experts on this subject based on the ideXlab platform.
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To reduce or to extend a Spacecraft Design lifetime
Journal of Spacecraft and Rockets, 2006Co-Authors: Joseph H. Saleh, Daniel E. Hastings, Juan-pablo Torres-padilla, Dava J. NewmanAbstract:The engineering and economic issues at stake for reducing or extending a complex system’s Design lifetime are investigated using a Spacecraft as an example. These issues are examined from an operator perspective, a manufacturer’s perspective, as well as from the perspective of society at large. The question of whether there is an optimal Design lifetime for complex engineering systems in general, and Spacecraft in particular, and what it takes to answer this question is addressed. Preliminary results indicate that optimal Design lifetimes do exist that maximize a system’s value metric. Therefore, even if it is technically feasible to field a system or launch Spacecraft with a longer lifetime, it is not necessarily in the best interest of an operator, and definitely not in the interest of the manufacturer, to do so. Preliminary results also show that the Design lifetime is, in the case of a Spacecraft, a key requirement in sizing various subsystems and, consequently, has a significant impact on the overall cost of the Spacecraft. Additionally, at the level of the entire space industry value chain, the Spacecraft Design lifetime is a powerful lever that can significantly impact the whole space industry’s performance. Overall, it is shown that the selection of a Spacecraft Design lifetime begs careful consideration and requires much more attention than it has received so far in the literature because its impact will ripple throughout an entire industry value chain.
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Spacecraft Design Lifetime
Journal of Spacecraft and Rockets, 2002Co-Authors: Joseph H. Saleh, Daniel E. Hastings, Dava J. NewmanAbstract:A general discussion of issues that drive and limit Spacecraft Design lifetime is presented. The effects of varying the Spacecraft lifetime requirement on different subsystems are explored, and typical Spacecraft mass andcost profiles are deduced. Quantitative analyses confirm that the Design lifetime is a key requirement in sizing various subsystems and significantly affects the Spacecraft mass and cost to initial operating capability. The analysis introduces a formally defined economic metric, the cost per operational day, to help guide the specification of the Design lifetime requirement. Preliminary results suggest that other factors should also be taken into account in specifying the Design lifetime, namely, the loss of value resulting from technology obsolescence as well as the volatility of the market the system is serving in the case of a commercial satellite.
C. R. Tooley - One of the best experts on this subject based on the ideXlab platform.
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Lunar Reconnaissance Orbiter Mission and Spacecraft Design
Space Science Reviews, 2010Co-Authors: C. R. Tooley, Martin B. Houghton, Richard S. Saylor, Cathy Peddie, David F. Everett, Charles L. Baker, Kristina N. SafdieAbstract:Launched June 18, 2009, with its primary mission scheduled to end September 2010, NASA’s Lunar Reconnaissance Orbiter will be the first observatory ever to spend an entire year orbiting and observing the Moon at a low altitude of just 50 km. The Spacecraft carries a wide variety of scientific instruments and will provide an extraordinary opportunity to study the lunar landscape at resolutions and over time scales never achieved before. This paper is intended as a companion to the series of papers released simultaneously in this journal detailing LRO’s instruments and their planned measurements. The paper describes the Design and key performance drivers of the LRO Spacecraft and overall mission Design. It presents a comprehensive description of the operation of the various systems that comprise the Spacecraft and illustrates how these systems enable achievement of the mission requirements.