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Nasa - One of the best experts on this subject based on the ideXlab platform.
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Development of deployable structures for large Space Platform systems, volume 1
2013Co-Authors: NasaAbstract:Generic deployable Spacecraft configurations and deployable Platform systems concepts were identified. Sizing, building block concepts, orbiter packaging, thermal analysis, cost analysis, and mass properties analysis as related to Platform systems integration are considered. Technology needs are examined and the major criteria used in concept selection are delineated. Requirements for deployable habitat modules, tunnels, and OTV hangars are considered.
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Evolutionary Space Platform concept study. Volume 3: Programmatics for manned Space Platform concepts
2013Co-Authors: Nasa, Mcdonnell-douglas Corp.Abstract:The programmatic data for the reference concept of the Manned Space Platform is presented. Details regarding work breakdown structure (WBS) and dictionary, the facilities and equipment required to produce the modules, the project schedule and logic diagram, a preliminary assessment of environmental impacts and details regarding the estimated costs for the reference concept are included. The proposed WBS which was developed to provide summary and system level segregation of the nonrecurring and recurring portions of the Manned Space Platform project is also included. The accompanying dictionary outlines the function and activities contained within each WBS element. The facility and equipment required to produce the various modules is discussed. Generally, required equipment is within the existing state of the art although the size of some of the items to be manufactured is a consideration. A preliminary manufacturing flow was also provided. The project schedules presented consist of the Master Project Summary Schedule, the Master Project Phasing Chart and the Logic Network.
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Space Platform expendables resupply concept definition study
2013Co-Authors: NasaAbstract:NASA has recognized that the capability for remote resupply of Space Platform expendable fluids will help transition Space utilization into a new era of operational efficiency and cost/effectiveness. The emerging Orbital Maneuvering System (OMV) in conjunction with an expendables resupply module will introduce the capability for fluid resupply enabling satellite lifetime extension at locations beyond the range of the Orbiter. This report summarizes a supplemental study to the original Phase A study and is presented as addenda to that study.
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Space Platform expendables resupply concept definition study, volume 2
2013Co-Authors: NasaAbstract:NASA has recognized that the capability for remote resupply of Space Platform expendable fluids will help transition Space utilization into a new era of operational efficiency and cost/effectiveness. The emerging Orbital Maneuvering System (OMV) in conjunction with an expendables resupply module will introduce the capability for fluid resupply enabling satellite lifetime extension at locations beyond the range of the Orbiter. This report summarizes a Phase A study of a remote resupply module for the OMV. Volume 2 represents study results.
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Space Platform expendables resupply concept definition study. Volume 3: Work breakdown structure and work breakdown structure dictionary
2013Co-Authors: NasaAbstract:The work breakdown structure (WBS) for the Space Platform Expendables Resupply Concept Definition Study is described. The WBS consists of a list of WBS elements, a dictionary of element definitions, and an element logic diagram. The list and logic diagram identify the interrelationships of the elements. The dictionary defines the types of work that may be represented by or be classified under each specific element. The Space Platform Expendable Resupply WBS was selected mainly to support the program planning, scheduling, and costing performed in the programmatics task (task 3). The WBS is neither a statement-of-work nor a work authorization document. Rather, it is a framework around which to define requirements, plan effort, assign responsibilities, allocate and control resources, and report progress, expenditures, technical performance, and schedule performance. The WBS element definitions are independent of make-or-buy decisions, organizational structure, and activity locations unless exceptions are specifically stated.
Leonid Gurvits - One of the best experts on this subject based on the ideXlab platform.
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Attitude Control of a Space Platform/Manipulator System Using Internal Motion
The International Journal of Robotics Research, 1994Co-Authors: Chris S.t. Fernandes, Leonid GurvitsAbstract:Attitude control of a Space Platform/manipulator system, using internal motion, is an example of a nonholonomic motion plan ning (NMP) problem arising from symmetry and conservation laws. Common to NMP problems are that an admissible con figuration Space path is constrained to a given nonholonomic distribution. We formulate the dynamic equations of a system consisting of a 3-DOF PUMA-like manipulator attached to a Space Platform (e.g., a Space station or a satellite) as an NMP problem and discuss the controllability of the system. Then we describe the application of a simple algorithm for obtaining approximate optimal solutions. We conclude with a descrip tion of simulation software implementing the algorithm and simulation results for two experiments.
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ICRA - Attitude control of Space Platform/manipulator system using internal motion
1992Co-Authors: C. Fernandes, Leonid GurvitsAbstract:The authors formulate the dynamic equations of a system consisting of a 3-degree-of-freedom Puma-like manipulator attached to a Space Platform (e.g. a Space station or a satellite) as an NMP (nonholonomic motion planning) problem and discuss controllability of the system. They describe the application of a simple algorithm for obtaining approximate optimal solutions. They conclude with results of a simulation experiment. >
F.c. Lee - One of the best experts on this subject based on the ideXlab platform.
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Space Platform power system hardware testbed
1991Co-Authors: D. Sable, Tom Sizemore, A. Patil, S. Deuty, J. Noon, B. H. Cho, F.c. LeeAbstract:The scope of the work on the NASA Space Platform includes the design of a multi-module, multi-phase boost regulator, and a voltage-fed, push-pull autotransformer converter for the battery discharger. A buck converter was designed for the charge regulator. Also included is the associated mode control electronics for the charger and discharger, as well as continued development of a comprehensive modeling and simulation tool for the system. The design of the multi-module boost converter is discussed for use as a battery discharger. An alternative battery discharger design is discussed using a voltage-fed, push-pull autotransformer converter. The design of the charge regulator is explained using a simple buck converter. The design of the mode controller and effects of locating the bus filter capacitor bank 20 feet away from the power ORU are discussed. A brief discussion of some alternative topologies for battery charging and discharging is included. The power system modeling is described.
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Design Considerations for a Solar Array Switching Unit
Proceedings of the 25th Intersociety Energy Conversion Engineering Conference, 1Co-Authors: A.r. Patil, S.h. Cho, F.c. LeeAbstract:This paper presents an analysis of the sequential switching shunt regulator unit (SSU) proposed for the Space station and Space Platform. The solar array and shunt regulator system is analyzed for ripple, output impedance, and stability. The performance of proportional gain and proportional-integrator (PI) controllers is compared. A design example is provided and an EASY5 simulation is presented for the regulation of the bus voltage by the SSU.
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Use of Nonlinear Design Optimization Techniques in the Comparison of Battery Discharger Topologies for the Space Platform
Proceedings of the 25th Intersociety Energy Conversion Engineering Conference, 1Co-Authors: Dan M. Sable, Bo-hyung Cho, F.c. LeeAbstract:A detailed comparison of a boost converter, a voltage-fed, autotransformer converter and a multi-module boost converter, designed specifically for the Space Platform battery discharger, is performed. Computer-based nonlinear optimization techniques are employed to facilitate an objective comparison.
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Modeling And Simulation Of The Space Platform Power System
Proceedings of the 25th Intersociety Energy Conversion Engineering Conference, 1Co-Authors: A.r. Patil, B. H. Cho, S.j. Kim, F.c. LeeAbstract:A comprehensive computer-aided modeling and simulation technique for the Space Platform power system is described. Large-signal and small-signal modeling is presented for the system components. The component models have been integrated to form the complete power system model. The system model is shown to be a powerful tool in simulating the behavior of the system with variation of illumination level and load. It can be used to study the bus regulation in each mode and to observe mode changes as the solar array is subjected to transitions from sunlight to eclipse and back to sunlight. System simulations show how the bus regulation is maintained by activating the shunt switching unit, the charger, or the discharger, depending on the available illumination level. The system model is suitable for verifying hardware results of for analyzing the performance of a proposed system where hardware testing is not feasible. The EASY5 dynamic analysis program is used as the host software for the modeling and simulation.
Chris S.t. Fernandes - One of the best experts on this subject based on the ideXlab platform.
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Attitude Control of a Space Platform/Manipulator System Using Internal Motion
The International Journal of Robotics Research, 1994Co-Authors: Chris S.t. Fernandes, Leonid GurvitsAbstract:Attitude control of a Space Platform/manipulator system, using internal motion, is an example of a nonholonomic motion plan ning (NMP) problem arising from symmetry and conservation laws. Common to NMP problems are that an admissible con figuration Space path is constrained to a given nonholonomic distribution. We formulate the dynamic equations of a system consisting of a 3-DOF PUMA-like manipulator attached to a Space Platform (e.g., a Space station or a satellite) as an NMP problem and discuss the controllability of the system. Then we describe the application of a simple algorithm for obtaining approximate optimal solutions. We conclude with a descrip tion of simulation software implementing the algorithm and simulation results for two experiments.
Thomas J. Mcmahon - One of the best experts on this subject based on the ideXlab platform.
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The Infrared Telescope in Space (IRTS)
The Astrophysical Journal, 1994Co-Authors: Hiroshi Murakami, James J. Bock, Minoru M. Freund, Takanori Hirao, Andrew E. Lange, H. Matsuhara, Toshio Matsumoto, Shuji Matsuura, Thomas J. McmahonAbstract:The Infrared Telescope in Space (IRTS) is a cryogenically cooled small infrared telescope that will fly aboard the small Space Platform Space Flyer Unit. It will survey approximately 10% of the sky with a relatively wide beam during its 20 day emission. Four focal-plane instruments will make simultaneous observations of the sky at wavelengths ranging from 1 to 1000 microns. The IRTS will provide significant information on cosmology, interstellar matter, late-type stars, and interplanetary dust. This paper describes the instrumentation and mission.
