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AIAA Infotech at Aerospace Conference and Exhibit 2011

作者： Hy, Franklin Gladden, Roy Allard, Dan Wallick, Michael Ground Data System Engineering Jet Propulsion Laboratory California Institute of Technology 264-214 Pasadena CA 91109 United States Planning and Execution System Engineering Jet Propulsion Laboratory California Institute of Technology 264-235 Pasadena CA 91109 United States Distributed Systems Technologies Jet Propulsion Laboratory California Institute of Technology 301-480 Pasadena CA 91109 United States Operations Planning Software Group Jet Propulsion Laboratory California Institute of Technology 301-250D Pasadena CA 91109 United States

ISBN: (纸本)9781600869440

Since the Mars Exploration Rovers (MER), Spirit and Opportunity, began their travels across the Martian surface in January of 2004, orbiting spacecraft such as the Mars 2001 Odyssey orbiter have relayed the majority of their collected scientific and operational data to and from Earth. From the beginning of those missions, it was evident that using orbiters to relay data to and from the surface of Mars was a vastly more efficient communications strategy in terms of power consumption and bandwidth compared to direct-to-Earth means. However, the coordination between the various spacecraft, which are largely managed independently and on differing commanding timelines, has always proven to be a challenge. Until recently, the ground operators of all these spacecraft have coordinated the movement of data through this network using a collection of ad hoc human interfaces and various, independent software tools. The Mars Relay Operations Service (MaROS) has been developed to manage the evolving needs of the Mars relay network, and specifically to standardize and integrate the relay planning and coordination data into a centralized infrastructure. This paper explores the journey of developing the MaROS system, from inception to delivery and acceptance by the Mars mission users. © 2011 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

关键词： Energy efficiency

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Goal-based operations: An overview

Goal-based operations: An overview

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2007 AIAA InfoTech at Aerospace Conference

作者： Dvorak, Daniel D. Ingham, Michel D. Morris, J. Richard Gersh, John NASA Jet Propulsion Laboratory California Institute of Technology Pasadena CA 91109 United States Applied Physics Laboratory Johns Hopkins University Laurel MD 20723 United States Planning and Execution Systems Section M/S 301-270 United States AIAA United States Flight Software Systems Engineering and Architectures Group M/S 301-225 Planning and Sequencing Systems Group M/S 301-250D System and Information Sciences Group M/S 2-236 United States

ISBN: (纸本)1563478935

Operating robotic space missions via time-based command sequences has become a limiting factor in the exploration, defense, and commercial sectors. Command sequencing was originally designed for comparatively simple and predictable missions, with safe-mode responses for most faults. This approach has been increasingly strained to accommodate today's more complex missions, which require advanced capabilities like autonomous fault diagnosis and response, vehicle mobility with hazard avoidance, opportunistic science observations, etc. Goal-based operation changes the fundamental basis of operations from imperative command sequences to declarative specifications of operational intent, termed goals. execution based on explicit intent simplifies operator workload by focusing on what to do rather than how to do it. The move toward goal-based operations, which has already begun in some space missions, involves changes and opportunities in several places: operational processes and tools, human interface design, planning and scheduling, control architecture, fault protection, and verification and validation. Further, the need for future interoperation among multiple goal-based systems suggests that attention be given to areas for standardization. This overview paper defines the concept of goal-based operations, reviews a history of steps in this direction, and discusses the areas of change and opportunity through comparison with the prevalent operational paradigm of command sequencing.

关键词： Robotics

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Solving Cassini's data glitch problem during coherency mode transition for Titan Radar observations

Solving Cassini's data glitch problem during coherency mode ...

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SpaceOps 2006 Conference - 9th International Conference on Space Operations

作者： Anderson, Yanhua Z. Morgan, H.D. Scarffe, V. Heventhal III, W.M. Doody, D.F. Callahan, P.S. Ray, T.L. Cheng, L.Y. Seal, D.A. Weld, K.R. Jet Propulsion Laboratory California Institute of Technology Planning and Execution Systems Section 4800 Oak Grove Drive MS. 230-250 Pasadena CA 91109 United States Jet Propulsion Laboratory California Institute of Technology Flight System Avionics Section 4800 Oak Grove Drive MS. 230-104 Pasadena CA 91109 United States Jet Propulsion Laboratory California Institute of Technology System Verification Validation and Operations Section 4800 Oak Grove Drive MS. 230-301 Pasadena CA 91109 United States Jet Propulsion Laboratory California Institute of Technology Radar Science and Engineering Section 4800 Oak Grove Drive MS. 300-319 Pasadena CA 91109 United States Jet Propulsion Laboratory California Institute of Technology Systems Engineering Section 4800 Oak Grove Drive MS. 230-205 Pasadena CA 91109 United States Jet Propulsion Laboratory California Institute of Technology Cassini Science and Uplink Office Solar System Exploration Office 4800 Oak Grove Drive MS. 230-260 Pasadena CA 91109 United States

ISBN: (纸本)9781624100512

We describe the problem of regular small telemetry losses incurred during coherency mode transitions in Cassini's telecommunication. The project did not originally plan any corrective steps for avoiding these data losses, because of 1) the disparity between the small durations of the transitions (1-2 min) and large playback capability losses (15 min) needed for bracketing the transition time spans and 2) the unpredictable content of data downlinking during the transitions. However, as the intense science data return from the tour began, it became apparent that the impact of these small losses can sometimes be significant. We provide two examples of the impact on Radar-dedicated Titan flybys. In general, the impacts are larger for high-rate data and for data acquired during a targeted flyby of Titan and other icy satellites. Although the content of data during a transition for every downlink pass is unpredictable, we are certain that some important data will be lost on downlink passes dedicated to transmit the flyby data and it does not matter what part of the data will be hit by the transitions. We collected more than 200 days of data from Cassini tour operations between June 2004 and February 2005 to analyze the distributions of the start time and duration of the transitions. We found that the occurrence of a transition can be predicted within a 5-min window, with 95 percent confidence. Given that, it is possible to eliminate the data losses by pausing playback at the beginning of a transition for 5 minutes and resuming playback after transition completion. We briefly describe three operational fixes as to how to implement the playback pause, with the pros and cons for each method. Finally, we report the results of the method chosen by the project and implemented on the spacecraft for several Titan and icy satellites flybys between September and October, 2005. © 2006 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

关键词： Space-based radar

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THE CONSTRUCTION OF VARIABLE PAYLOAD SHIPS

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NAVAL ENGINEERS JOURNAL 1982年第2期94卷 179-199页

作者： THOMPSON, DH THORELL, LM Daniel H. Thompson Jr.:is a native of Louisville Kentucky. He graduated from Webb Institute of Naval Architecture in 1957. He was an Engineering Duty Officer in theUNITED STATES NAVYprimarily in the Far East responsible for ship repair and overhaul. He joined Sparkman & Stephens Inc. New York City as Assistant to the Chief Engineer in 1963 and worked on commercial military and private contracts. He has worked for Bath Iron Works since 1967. Between 1967 and 1971 he served first as Project Engineer on the DLG-16 Class Ship Modernization Program which involved eight ships and later as the Assistant to the Production Manager when he assumed the responsibilities for production management administration and sea trial coordination. He organized and directed cost reduction programs and led the development of a comprehensive management administration information system. Between 1971 and 1972 Mr. Thompson served as the Facilities Project Manager responsible for the execution of a nine million dollar shipyard facilities improvement program. In 1972 Mr. Thompson was appointed as the Producibility Assurance Manager for the FFG-7 Program. In this capacity he reviewed the detail design work and coordinated the early activities of the subcontractor responsible for detail design. He was also responsible for the development of the FFG-7 Class Producibility Assurance Manual which provided guidance to the detail designers on production/design integration. During the DG-47 (now CG-47) studies at BIW Mr. Thompson served as the Deputy Program Manager for DG-47 Technical Characterization in 1977. At present Mr. Thompson is working as a Project Engineer in the Technical Department. He is responsible for coordinating the engineering work on new DDGX and Variable Payload Ship projects. On special assignment he is also supporting the Cost Reduction Program at BIW as Chairman of the Technical Committee. Mr. Thompson is a member of SNAME and ASNE and is a licensed professional engineer in New York and Maine. Len Thorell:is a

The decoupling of combat systems from the platform makes it possible for shipyards and combat system suppliers to work in parallel without schedule or technological conflict. Great benefit is derived from building one, standard platform able to accommodate a variety of combat systems. The capability to build and test the payload modules independently, in a well equipped shore-based facility, means higher production efficiency and improved quality control. The standardization of payload-platform interfaces means that the detail design and construction of foundations and distributive systems need not be delayed if some of the combat system components are being upgraded at the time when the ship is in construction. Additionally, shipyards recognize the value of the variable payload ship concept for major combat systems and weapons upgrades. Analysis shows that combat system changes will not lie on the critical path from a scheduling point of view if the payload items are modularized and conform to the Ship systems engineering Standards. The shipyards intend to participate actively in the conservation of tenth-scale models and full-scale mock-ups. These mock-ups should prove valuable in the definition of interface requirements which must be incorporated in the Ship system engineering Standards. The module installation procedures and clearance requirements for both weapons modules and pelletized electronics can be checked in this effective way. Variable payload ship platform construction poses no technical problems as far as new facility requirements are concerned. Shipyards interested in assembling, testing, and installing payload modules would, however, have to use appropriate buildings, equipment, and cranes. These capital requirements are significant but reasonable for those yards that are likely to be interested in building frigates, destroyers, or cruisers. Furthermore, these yards generally plan for production improvements through better facilities, many of which

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