Publications
2002 |
Enright, John P; Sedwick, Raymond J; Miller, David W High-fidelity simulation for spacecraft autonomy development Journal Article Canadian aeronautics and space journal, 48 (1), pp. 51–59, 2002. BibTeX | Tags: @article{enright2002high, title = {High-fidelity simulation for spacecraft autonomy development}, author = {John P Enright and Raymond J Sedwick and David W Miller}, year = {2002}, date = {2002-01-01}, journal = {Canadian aeronautics and space journal}, volume = {48}, number = {1}, pages = {51--59}, publisher = {NRC Research Press Ottawa, Canada}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Mallory, Gregory J W; Miller, David W Increasing the numerical robustness of balanced model reduction Journal Article Journal of Guidance, Control, and Dynamics, 25 (3), pp. 596–598, 2002. BibTeX | Tags: @article{w2002increasing, title = {Increasing the numerical robustness of balanced model reduction}, author = {Gregory J W. Mallory and David W Miller}, year = {2002}, date = {2002-01-01}, journal = {Journal of Guidance, Control, and Dynamics}, volume = {25}, number = {3}, pages = {596--598}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Mun-Choong Kong, Edmund Spacecraft Formation Flight Exploiting Potential Fields PhD Thesis 2002. BibTeX | Tags: @phdthesis{Miller2002, title = {Spacecraft Formation Flight Exploiting Potential Fields}, author = {Edmund {Mun-Choong Kong}}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Onishi, Tatsuo Numerical Study of Current Collection by an Orbiting Bare Tether PhD Thesis 2002. BibTeX | Tags: @phdthesis{Onishi, title = {Numerical Study of Current Collection by an Orbiting Bare Tether}, author = {Tatsuo Onishi}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Pacros, Anne Instruments Design and Testing for a Hall Thruster Plume Experiment on the Space Shuttle By PhD Thesis 2002. BibTeX | Tags: @phdthesis{Pacros2002, title = {Instruments Design and Testing for a Hall Thruster Plume Experiment on the Space Shuttle By}, author = {Anne Pacros}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
a Pohlman, Nicholas Estimation and Control of a Multi-Vehicle Testbed Using GPS Doppler Sensing By PhD Thesis 2002. BibTeX | Tags: @phdthesis{pohlmanEstimationControlMultiVehicle2002, title = {Estimation and Control of a Multi-Vehicle Testbed Using GPS Doppler Sensing By}, author = {Nicholas a Pohlman}, year = {2002}, date = {2002-01-01}, number = {May 2000}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Radcliffe, Andrew D B A Real-Time Simulator for the SPHERES Formation Flying Satellites Testbed PhD Thesis 2002. @phdthesis{radcliffeRealTimeSimulatorSPHERES2002, title = {A Real-Time Simulator for the SPHERES Formation Flying Satellites Testbed}, author = {Andrew D B Radcliffe}, year = {2002}, date = {2002-01-01}, number = {May}, abstract = {A software simulator for the SPHERES formation flight testbed, the GFLOPS SPHERES Simulator (GSS), has been developed. The Synchronized Position, Hold, Engage, and Reorient Experimental Satellites (SPHERES) testbed consists of three miniature spacecraft (or SPHERES), each with their own power, avionics, navigation, communications, and propulsion. These spacecraft will operate inside the International Space Station to test formation flying, autonomy, and autonomous rendezvous and docking algorithms. The GSS runs on the Generalized FLight Operations Processing Simulator (GFLOPS), a realtime embedded hardware testbed for the simulation of distributed space systems. SPHERES flight code can be run in the simulator to test the performance of guest investigator algorithms. The simulator models the characteristics of SPHERES hardware, including thrusters and metrology sensors, and simulates the dynamics of the spacecraft. Features include the ability to simulate SPHERE-SPHERE and SPHERE-wall collisions, as well as docking between SPHERES. A 3-D viewer allows users to monitor the motion of SPHERES within the test space and log the results for later playback. A command window allows users to view telemetry from the units and send them commands. Methods of measuring flight code processor utilization are discussed. Results are presented from sample simulations that demonstrate the capabilities of the simulator. Simulations include a leader-follower control architecture, a SPHERE-SPHERE collision, passive docking, and cooperative docking. Suggestions are given for future improvements to the simulator.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } A software simulator for the SPHERES formation flight testbed, the GFLOPS SPHERES Simulator (GSS), has been developed. The Synchronized Position, Hold, Engage, and Reorient Experimental Satellites (SPHERES) testbed consists of three miniature spacecraft (or SPHERES), each with their own power, avionics, navigation, communications, and propulsion. These spacecraft will operate inside the International Space Station to test formation flying, autonomy, and autonomous rendezvous and docking algorithms. The GSS runs on the Generalized FLight Operations Processing Simulator (GFLOPS), a realtime embedded hardware testbed for the simulation of distributed space systems. SPHERES flight code can be run in the simulator to test the performance of guest investigator algorithms. The simulator models the characteristics of SPHERES hardware, including thrusters and metrology sensors, and simulates the dynamics of the spacecraft. Features include the ability to simulate SPHERE-SPHERE and SPHERE-wall collisions, as well as docking between SPHERES. A 3-D viewer allows users to monitor the motion of SPHERES within the test space and log the results for later playback. A command window allows users to view telemetry from the units and send them commands. Methods of measuring flight code processor utilization are discussed. Results are presented from sample simulations that demonstrate the capabilities of the simulator. Simulations include a leader-follower control architecture, a SPHERE-SPHERE collision, passive docking, and cooperative docking. Suggestions are given for future improvements to the simulator. |
Henry, Melvin Model-Based Estimation of Probabilistic Hybrid Automata PhD Thesis 2002. @phdthesis{Science2002a, title = {Model-Based Estimation of Probabilistic Hybrid Automata}, author = {Melvin Henry}, year = {2002}, date = {2002-01-01}, abstract = {The ability to monitor and diagnose complex physical systems is critical for constructing highly autonomous artifacts that can function robustly in harsh environments over a long period of time. To accomplish this, we need to use high fidelity models that describe both the discrete stochastic behavior and the continuous dynamics of these complex systems. These models are used by a hybrid monitoring and diagnosis capability that tracks a system's dynamics as it moves between distinctive behavioral modes. In this thesis, we address the challenge of learning these hybrid discrete/continuous models. We introduce a Hybrid Parameter Estimation System that extracts parameter estimates from sensor data. First, we review a method for Hybrid Modeling based on Probabilistic Hybrid Automata (PHA) [Hofbaur and Williams, 2002]. Second, we introduce Hybrid Parameter Estimation as a technique for learning the parameters of a PHA, by unifying standard nonlinear estimation techniques with classical probabilistic estimation techniques. Finally, we introduce the Hybrid Expectation Maximization algorithm for computing hybrid estimates by combining Hybrid Parameter Estimation with prior work on Hybrid State Estimation. This approach tracks the most desirable estimates based on statistical measure of probability. We demonstrate this algorithm on a simulated Mars habitat called BIO-Plex.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } The ability to monitor and diagnose complex physical systems is critical for constructing highly autonomous artifacts that can function robustly in harsh environments over a long period of time. To accomplish this, we need to use high fidelity models that describe both the discrete stochastic behavior and the continuous dynamics of these complex systems. These models are used by a hybrid monitoring and diagnosis capability that tracks a system's dynamics as it moves between distinctive behavioral modes. In this thesis, we address the challenge of learning these hybrid discrete/continuous models. We introduce a Hybrid Parameter Estimation System that extracts parameter estimates from sensor data. First, we review a method for Hybrid Modeling based on Probabilistic Hybrid Automata (PHA) [Hofbaur and Williams, 2002]. Second, we introduce Hybrid Parameter Estimation as a technique for learning the parameters of a PHA, by unifying standard nonlinear estimation techniques with classical probabilistic estimation techniques. Finally, we introduce the Hybrid Expectation Maximization algorithm for computing hybrid estimates by combining Hybrid Parameter Estimation with prior work on Hybrid State Estimation. This approach tracks the most desirable estimates based on statistical measure of probability. We demonstrate this algorithm on a simulated Mars habitat called BIO-Plex. |
Tillerson, Michael Co-Ordination and Control of Distributed Spacecraft Systems Using Convex Optimization Techniques PhD Thesis 2002, ISSN: 10498923. Abstract | Links | BibTeX | Tags: Distributed spacecraft systems, Formation flying control, Linear programming, Real-time trajectory optimization @phdthesis{tillersonCoordinationControlDistributed2002, title = {Co-Ordination and Control of Distributed Spacecraft Systems Using Convex Optimization Techniques}, author = {Michael Tillerson}, doi = {10.1002/rnc.683}, issn = {10498923}, year = {2002}, date = {2002-01-01}, volume = {12}, number = {2-3}, abstract = {Formation flying of multiple spacecraft is an enabling technology for many future space science missions. However, the co-ordination and control of these instruments poses many difficult design challenges. This paper presents fuel/time-optimal control algorithms for a co-ordination and control architecture that was designed for a fleet of spacecraft. This architecture includes low-level formation-keeping algorithms and a high-level fleet planner that creates trajectories to re-size or re-target the formation. The trajectory and formation-keeping optimization algorithms are based on the solutions of linear and integer programming problems. The result is a very flexible optimization framework that can be used off-line to analyse various aspects of the mission design and in real time as part of an onboard autonomous formation flying control system. The overall control approach is demonstrated using a nonlinear simulation environment that includes realistic measurement noises, disturbances, and actuator nonlinearities.}, keywords = {Distributed spacecraft systems, Formation flying control, Linear programming, Real-time trajectory optimization}, pubstate = {published}, tppubtype = {phdthesis} } Formation flying of multiple spacecraft is an enabling technology for many future space science missions. However, the co-ordination and control of these instruments poses many difficult design challenges. This paper presents fuel/time-optimal control algorithms for a co-ordination and control architecture that was designed for a fleet of spacecraft. This architecture includes low-level formation-keeping algorithms and a high-level fleet planner that creates trajectories to re-size or re-target the formation. The trajectory and formation-keeping optimization algorithms are based on the solutions of linear and integer programming problems. The result is a very flexible optimization framework that can be used off-line to analyse various aspects of the mission design and in real time as part of an onboard autonomous formation flying control system. The overall control approach is demonstrated using a nonlinear simulation environment that includes realistic measurement noises, disturbances, and actuator nonlinearities. |
Sou, Kin Cheong Fast Time Domain Simulation for Large Order Hybrid PhD Thesis 2002. BibTeX | Tags: @phdthesis{Weck2002, title = {Fast Time Domain Simulation for Large Order Hybrid}, author = {Kin Cheong Sou}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Wertz, Julie Reliability and Productivity Modeling for the Optimization of Separated Spacecraft Interferometers PhD Thesis 2002. BibTeX | Tags: @phdthesis{Wertz2002, title = {Reliability and Productivity Modeling for the Optimization of Separated Spacecraft Interferometers}, author = {Julie Wertz}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Baek, Seungmin Entry Optimization Using Mixed Integer Linear Programming PhD Thesis 2002, ISSN: 20054092. Abstract | Links | BibTeX | Tags: Decision making, game theory, military operation, MILP (mixed integer linear programming), resource allocation @phdthesis{baekEntryOptimizationUsing2002, title = {Entry Optimization Using Mixed Integer Linear Programming}, author = {Seungmin Baek}, doi = {10.1007/s12555-014-0270-6}, issn = {20054092}, year = {2002}, date = {2002-01-01}, volume = {14}, number = {1}, abstract = {An appropriate selection of agents to participate in a confrontation such as a game or combat depends on the types of the opposing team. This paper investigates the problem of determining a combination of agents to fight in a combat between two forces. When the types of enemy agents committed to the combat are not known, game theory provides the best response to the opponent. The entry game is solved by using mixed integer linear programming (MILP) to consider the constraints on resources in a game theoretic approach. Simulations for the examples involving three different sets of military forces are performed using an optimization tool, which demonstrates that the optimal entry is properly selected corresponding to the opposing force.}, keywords = {Decision making, game theory, military operation, MILP (mixed integer linear programming), resource allocation}, pubstate = {published}, tppubtype = {phdthesis} } An appropriate selection of agents to participate in a confrontation such as a game or combat depends on the types of the opposing team. This paper investigates the problem of determining a combination of agents to fight in a combat between two forces. When the types of enemy agents committed to the combat are not known, game theory provides the best response to the opponent. The entry game is solved by using mixed integer linear programming (MILP) to consider the constraints on resources in a game theoretic approach. Simulations for the examples involving three different sets of military forces are performed using an optimization tool, which demonstrates that the optimal entry is properly selected corresponding to the opposing force. |
Bellingham, John Saunders Coordination and Control of UAV Fleets Using Mixed-Integer Linear Programming PhD Thesis 2002. BibTeX | Tags: @phdthesis{Bellingham2002a, title = {Coordination and Control of UAV Fleets Using Mixed-Integer Linear Programming}, author = {John Saunders Bellingham}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Chen, Allen Propulsion System Characterization for the SPHERES Formation Flight and Docking Testbed PhD Thesis 2002. Abstract | BibTeX | Tags: SPHERES propulsion system characterization, ★ @phdthesis{Chen2002, title = {Propulsion System Characterization for the SPHERES Formation Flight and Docking Testbed}, author = {Allen Chen}, year = {2002}, date = {2002-01-01}, abstract = {The MIT Space Systems Laboratory is developing the SPHERES Formation Flight and Docking testbed for the validation of high risk metrology, control, and autonomy technologies. Knowledge of the testbeddbend s actuation system is critical both to the performance of SPHERES as a controls testbed and to the operations of the testbed onboard the International Space Station. This thesis presents work that characterizes the SPHERES propulsion system, the testbeddbend s actuator. The flight design of the SPHERES testbed is presented with particular focus and detail given to the design of the propulsion system. Performance and performance variations of the system are first theoretically determined and then compared to data generated experimentally. Trends in the experimental results are identified and modeled, yielding greater insight into the propulsion systemdbend s workings. Better knowledge of the propulsion system allows refinement of the plant control model, resulting in better estimation of propellant consumption and truer performance when evaluating control algorithms. Performance variations resulting from manufacturing, system settings, and usage are identified and quantified. This leads directly to the development of correction schemes that help to mitigate the undesirable and unintended performance variations that affect tracking. Finally, a process for extending the work in this thesis is presented.}, keywords = {SPHERES propulsion system characterization, ★}, pubstate = {published}, tppubtype = {phdthesis} } The MIT Space Systems Laboratory is developing the SPHERES Formation Flight and Docking testbed for the validation of high risk metrology, control, and autonomy technologies. Knowledge of the testbeddbend s actuation system is critical both to the performance of SPHERES as a controls testbed and to the operations of the testbed onboard the International Space Station. This thesis presents work that characterizes the SPHERES propulsion system, the testbeddbend s actuator. The flight design of the SPHERES testbed is presented with particular focus and detail given to the design of the propulsion system. Performance and performance variations of the system are first theoretically determined and then compared to data generated experimentally. Trends in the experimental results are identified and modeled, yielding greater insight into the propulsion systemdbend s workings. Better knowledge of the propulsion system allows refinement of the plant control model, resulting in better estimation of propellant consumption and truer performance when evaluating control algorithms. Performance variations resulting from manufacturing, system settings, and usage are identified and quantified. This leads directly to the development of correction schemes that help to mitigate the undesirable and unintended performance variations that affect tracking. Finally, a process for extending the work in this thesis is presented. |
Cheng, Shannon Yun-Ming Computational Modeling of a Hall Thruster Plasma Plume in a Vacuum Tank PhD Thesis 2002. BibTeX | Tags: @phdthesis{Chgen, title = {Computational Modeling of a Hall Thruster Plasma Plume in a Vacuum Tank}, author = {Shannon Yun-Ming Cheng}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Chung, Soon-Jo Design and Implementation of Sparse Aperture Imaging Systems PhD Thesis 2002, ISSN: 0277786X. Abstract | Links | BibTeX | Tags: @phdthesis{chungDesignImplementationSparse2002, title = {Design and Implementation of Sparse Aperture Imaging Systems}, author = {Soon-Jo Chung}, doi = {10.1117/12.460077}, issn = {0277786X}, year = {2002}, date = {2002-01-01}, volume = {4849}, abstract = {In order to better understand the technological difficulties involved in designing and building a sparse aperture array, the challenge of building a white light Golay-3 telescope was undertaken. The MIT Adaptive Reconnaissance Golay-3 Optical Satellite (ARGOS) project exploits wide-angle Fizeau interferometer technology with an emphasis on modularity in the optics and spacecraft subsystems. Unique design procedures encompassing the nature of coherent wavefront sensing, control and combining as well as various system engineering aspects to achieve cost effectiveness, are developed. To demonstrate a complete spacecraft in a 1-g environment, the ARGOS system is mounted on a frictionless air-bearing, and has the ability to track fast orbiting satellites like the ISS or the planets. Wavefront sensing techniques are explored to mitigate initial misalignment and to feed back real-time aberrations into the optical control loop. This paper presents the results and the lessons learned from the conceive, design and implementation phases of ARGOS. A preliminary assessment shows that the beam combining problem is the most challenging aspect of sparse optical arrays. The need for optical control is paramount due to tight beam combining tolerances. The wavefront sensing/control requirements appear to be a major technology and cost driver.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } In order to better understand the technological difficulties involved in designing and building a sparse aperture array, the challenge of building a white light Golay-3 telescope was undertaken. The MIT Adaptive Reconnaissance Golay-3 Optical Satellite (ARGOS) project exploits wide-angle Fizeau interferometer technology with an emphasis on modularity in the optics and spacecraft subsystems. Unique design procedures encompassing the nature of coherent wavefront sensing, control and combining as well as various system engineering aspects to achieve cost effectiveness, are developed. To demonstrate a complete spacecraft in a 1-g environment, the ARGOS system is mounted on a frictionless air-bearing, and has the ability to track fast orbiting satellites like the ISS or the planets. Wavefront sensing techniques are explored to mitigate initial misalignment and to feed back real-time aberrations into the optical control loop. This paper presents the results and the lessons learned from the conceive, design and implementation phases of ARGOS. A preliminary assessment shows that the beam combining problem is the most challenging aspect of sparse optical arrays. The need for optical control is paramount due to tight beam combining tolerances. The wavefront sensing/control requirements appear to be a major technology and cost driver. |
Eepoel, John Van M Achieving Real-time Mode Estimation through Offline Compilation PhD Thesis 2002. @phdthesis{Eepoel2002, title = {Achieving Real-time Mode Estimation through Offline Compilation}, author = {John Van M Eepoel}, year = {2002}, date = {2002-01-01}, abstract = {As exploration of our solar system and outerspace move into the future, spacecraft are being developed to venture on increasingly challenging missions with bold objectives. The spacecraft tasked with completing these missions are becoming progressively more complex. This increases the potential for mission failure due to hardware malfunctions and unexpected spacecraft behavior. A solution to this problem lies in the development of an advanced fault management system. Fault management enables spacecraft to respond to failures and take repair actions so that it may continue its mission. The two main approaches developed for spacecraft fault management have been rule-based and model-based systems. Rules map sensor information to system behaviors, thus achieving fast response times, and making the actions of the fault management system explicit. These rules are developed by having a human reason through the interactions between spacecraft components. This process is limited by the number of interactions a human can reason about correctly. In the model-based approach, the human provides component models, and the fault management system reasons automatically about system wide interactions and complex fault combinations. This approach improves correctness, and makes explicit the underlying system models, whereas these are implicit in the rule-based approach. We propose a fault detection engine, Compiled Mode Estimation (CME) that unifies the strengths of the rule-based and model-based approaches. CME uses a compiled model to determine spacecraft behavior more accurately. Reasoning related to fault detection is compiled in an off-line process into a set of concurrent, localized diagnostic rules. These are then combined on-line along with sensor information to reconstruct the diagnosis of the system. These rules enable a human to inspect the diagnostic consequences of CME. Additionally, CME is capable of reasoning through component interactions automatically and still provide fast and correct responses. The implementation of this engine has been tested against the NEAR spacecraft advanced rule-based system, resulting in detection of failures beyond that of the rules. This evolution in fault detection will enable future missions to explore the furthest reaches of the solar system without the burden of human intervention to repair failed components.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } As exploration of our solar system and outerspace move into the future, spacecraft are being developed to venture on increasingly challenging missions with bold objectives. The spacecraft tasked with completing these missions are becoming progressively more complex. This increases the potential for mission failure due to hardware malfunctions and unexpected spacecraft behavior. A solution to this problem lies in the development of an advanced fault management system. Fault management enables spacecraft to respond to failures and take repair actions so that it may continue its mission. The two main approaches developed for spacecraft fault management have been rule-based and model-based systems. Rules map sensor information to system behaviors, thus achieving fast response times, and making the actions of the fault management system explicit. These rules are developed by having a human reason through the interactions between spacecraft components. This process is limited by the number of interactions a human can reason about correctly. In the model-based approach, the human provides component models, and the fault management system reasons automatically about system wide interactions and complex fault combinations. This approach improves correctness, and makes explicit the underlying system models, whereas these are implicit in the rule-based approach. We propose a fault detection engine, Compiled Mode Estimation (CME) that unifies the strengths of the rule-based and model-based approaches. CME uses a compiled model to determine spacecraft behavior more accurately. Reasoning related to fault detection is compiled in an off-line process into a set of concurrent, localized diagnostic rules. These are then combined on-line along with sensor information to reconstruct the diagnosis of the system. These rules enable a human to inspect the diagnostic consequences of CME. Additionally, CME is capable of reasoning through component interactions automatically and still provide fast and correct responses. The implementation of this engine has been tested against the NEAR spacecraft advanced rule-based system, resulting in detection of failures beyond that of the rules. This evolution in fault detection will enable future missions to explore the furthest reaches of the solar system without the burden of human intervention to repair failed components. |
Otero, Alvar Saenz; Chen, Allen; Miller, David W; Hilstad, Mark SPHERES: Development of an ISS laboratory for formation flight and docking research Inproceedings Aerospace Conference Proceedings, 2002. IEEE, pp. 1–1, IEEE 2002. BibTeX | Tags: @inproceedings{otero2002spheres, title = {SPHERES: Development of an ISS laboratory for formation flight and docking research}, author = {Alvar Saenz Otero and Allen Chen and David W Miller and Mark Hilstad}, year = {2002}, date = {2002-01-01}, booktitle = {Aerospace Conference Proceedings, 2002. IEEE}, volume = {1}, pages = {1--1}, organization = {IEEE}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Miller, David W; Brodeur, Doris R The CDIO capstone course: An innovation in undergraduate systems engineering education Journal Article age, 7 , pp. 1, 2002. BibTeX | Tags: @article{miller2002cdio, title = {The CDIO capstone course: An innovation in undergraduate systems engineering education}, author = {David W Miller and Doris R Brodeur}, year = {2002}, date = {2002-01-01}, journal = {age}, volume = {7}, pages = {1}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Otero, Alvar Saenz; Chen, Allen; Miller, David W; Hilstad, Mark SPHERES: Development of an ISS laboratory for formation flight and docking research Inproceedings Aerospace Conference Proceedings, 2002. IEEE, pp. 1–1, IEEE 2002. BibTeX | Tags: @inproceedings{otero2002spheresb, title = {SPHERES: Development of an ISS laboratory for formation flight and docking research}, author = {Alvar Saenz Otero and Allen Chen and David W Miller and Mark Hilstad}, year = {2002}, date = {2002-01-01}, booktitle = {Aerospace Conference Proceedings, 2002. IEEE}, volume = {1}, pages = {1--1}, organization = {IEEE}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Hilstad, Mark Ole A Multi-Vehicle Testbed and Interface Framework for the Development and Verification of Separated Spacecraft Control Algorithms PhD Thesis 2002. BibTeX | Tags: @phdthesis{Hilstad2002, title = {A Multi-Vehicle Testbed and Interface Framework for the Development and Verification of Separated Spacecraft Control Algorithms}, author = {Mark Ole Hilstad}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Jilla, Cyrus D 2002. Abstract | Links | BibTeX | Tags: @phdthesis{jillaMultiobjectiveMultidisciplinaryDesign2002, title = {A Multiobjective, Multidisciplinary Design Optimization Methodology for the Conceptual Design of Distributed Satellite Systems}, author = {Cyrus D Jilla}, doi = {10.2514/6.2002-5491}, year = {2002}, date = {2002-01-01}, abstract = {A multiobjective, multidisciplinary design optimization methodology for mathematically modeling the distributed satellite system (DSS) conceptual design problem as an optimization problem has been developed. The trade space for distributed satellite systems can be enormous - too large to enumerate, analyze, and compare all possible architectures. The seven-step methodology enables an efficient search of the trade space for the best families of architectures, and explores architectures that might not otherwise be considered during the conceptual design phase, the phase of a DSS program in which the majority of lifecycle cost gets locked in. Four classes of multidisciplinary design optimization (MDO) techniques are investigated - Taguchi, heuristic, gradient, and univariate methods. The heuristic simulated annealing (SA) algorithm found the best DSS architectures with the greatest consistency due to its ability to escape local optima within a nonconvex trade space. Accordingly, this SA algorithm forms the core single objective MDO algorithm in the methodology. The DSS conceptual design problem scope is then broadened by expanding from single objective to multiobjective optimization problems, and two variant multiobjective SA algorithms are developed. The utility in knowing the global Pareto boundary of a DSS trade space is presented, and several methods are explored for approximating the true global Pareto boundary with only a limited knowledge of the full DSS trade space. The versatility of the methodology is demonstrated through its application to the conceptual design of a commercial broadband satellite communications mission. The methodology serves as a powerful, versatile systems engineering tool for the conceptual design of distributed satellite systems. textcopyright 2002 by the MIT Space Systems Laboratory.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } A multiobjective, multidisciplinary design optimization methodology for mathematically modeling the distributed satellite system (DSS) conceptual design problem as an optimization problem has been developed. The trade space for distributed satellite systems can be enormous - too large to enumerate, analyze, and compare all possible architectures. The seven-step methodology enables an efficient search of the trade space for the best families of architectures, and explores architectures that might not otherwise be considered during the conceptual design phase, the phase of a DSS program in which the majority of lifecycle cost gets locked in. Four classes of multidisciplinary design optimization (MDO) techniques are investigated - Taguchi, heuristic, gradient, and univariate methods. The heuristic simulated annealing (SA) algorithm found the best DSS architectures with the greatest consistency due to its ability to escape local optima within a nonconvex trade space. Accordingly, this SA algorithm forms the core single objective MDO algorithm in the methodology. The DSS conceptual design problem scope is then broadened by expanding from single objective to multiobjective optimization problems, and two variant multiobjective SA algorithms are developed. The utility in knowing the global Pareto boundary of a DSS trade space is presented, and several methods are explored for approximating the true global Pareto boundary with only a limited knowledge of the full DSS trade space. The versatility of the methodology is demonstrated through its application to the conceptual design of a commercial broadband satellite communications mission. The methodology serves as a powerful, versatile systems engineering tool for the conceptual design of distributed satellite systems. textcopyright 2002 by the MIT Space Systems Laboratory. |
Kenny, S P Optimal Rejection of Nonstationary Narrowband Disturbances for Flexible Systems PhD Thesis 2002. BibTeX | Tags: @phdthesis{Kenny2002, title = {Optimal Rejection of Nonstationary Narrowband Disturbances for Flexible Systems}, author = {S P Kenny}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Kimbrel, Michael Scott Optimization of Electric Propulsion Orbit Raising PhD Thesis 2002. BibTeX | Tags: @phdthesis{Kimbrel2002, title = {Optimization of Electric Propulsion Orbit Raising}, author = {Michael Scott Kimbrel}, year = {2002}, date = {2002-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
2001 |
Marais, Karen The Development and Analysis of Scanned Pattern Interferometric Radar PhD Thesis 2001. BibTeX | Tags: @phdthesis{maraisDevelopmentAnalysisScanned2001, title = {The Development and Analysis of Scanned Pattern Interferometric Radar}, author = {Karen Marais}, year = {2001}, date = {2001-01-01}, number = {September}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Wong, Jonathan K Implementation of Multi-Layer Active Structural-Acoustic Transmission Control PhD Thesis 2001. BibTeX | Tags: @phdthesis{Maschinen, title = {Implementation of Multi-Layer Active Structural-Acoustic Transmission Control}, author = {Jonathan K Wong}, year = {2001}, date = {2001-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Merchant, Christopher Ali Active Noise Control Using Glow Discharge Plasma Panels PhD Thesis 2001. BibTeX | Tags: @phdthesis{Merchant2001, title = {Active Noise Control Using Glow Discharge Plasma Panels}, author = {Christopher Ali Merchant}, year = {2001}, date = {2001-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
M'Guire, Thomas J Aero-Assisted Orbital Transfer Vehicles Utilizing Atmosphere Ingestion PhD Thesis 2001. Abstract | Links | BibTeX | Tags: @phdthesis{mguireAeroassistedOrbitalTransfer2001, title = {Aero-Assisted Orbital Transfer Vehicles Utilizing Atmosphere Ingestion}, author = {Thomas J M'Guire}, doi = {10.2514/6.2001-840}, year = {2001}, date = {2001-01-01}, abstract = {The atmosphere present in the low earth orbits can be used to provide working fluid to an electric propulsion system. As the craft plows through low earth orbit (-175 - 225 km), incident gases are collected, ionized and routed through a high power electric thruster. A spacecraft utilizing this concept can generate thrust without expending on-board propellant. The performance of the system is explored in this paper. An example mission of interest, orbital transfer of communications satellites from low earth orbit, LEO, to geostationary earth orbit, GEO, is presented and compared to both the state-of-the-art and a proposed solar thermal orbital transfer vehicle from the Boeing company. Performance increases possible with this system include lower cost per kilogram to the higher orbits, smaller and more cost effective launch vehicles for a given payload, and fourfold increases in GEO capability of current launch vehicles. textcopyright 2001 by Thomas J. Mtextsterling Guire.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } The atmosphere present in the low earth orbits can be used to provide working fluid to an electric propulsion system. As the craft plows through low earth orbit (-175 - 225 km), incident gases are collected, ionized and routed through a high power electric thruster. A spacecraft utilizing this concept can generate thrust without expending on-board propellant. The performance of the system is explored in this paper. An example mission of interest, orbital transfer of communications satellites from low earth orbit, LEO, to geostationary earth orbit, GEO, is presented and compared to both the state-of-the-art and a proposed solar thermal orbital transfer vehicle from the Boeing company. Performance increases possible with this system include lower cost per kilogram to the higher orbits, smaller and more cost effective launch vehicles for a given payload, and fourfold increases in GEO capability of current launch vehicles. textcopyright 2001 by Thomas J. Mtextsterling Guire. |
Jilla, Cyrus D; Miller, David W Assessing the performance of a heuristic simulated annealing algorithm for the design of distributed satellite systems Journal Article Acta Astronautica, 48 (5-12), pp. 529–543, 2001. BibTeX | Tags: @article{jilla2001assessing, title = {Assessing the performance of a heuristic simulated annealing algorithm for the design of distributed satellite systems}, author = {Cyrus D Jilla and David W Miller}, year = {2001}, date = {2001-01-01}, journal = {Acta Astronautica}, volume = {48}, number = {5-12}, pages = {529--543}, publisher = {Elsevier}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Shaw, Graeme B; Miller, David W; Hastings, Daniel E Development of the quantitative generalized information network analysis methodology for satellite systems Journal Article Journal of Spacecraft and Rockets, 38 (2), pp. 257–269, 2001. BibTeX | Tags: @article{shaw2001development, title = {Development of the quantitative generalized information network analysis methodology for satellite systems}, author = {Graeme B Shaw and David W Miller and Daniel E Hastings}, year = {2001}, date = {2001-01-01}, journal = {Journal of Spacecraft and Rockets}, volume = {38}, number = {2}, pages = {257--269}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Reichbach, Jeffrey G Micropropulsion System Selection for Precision Formation Flying Satellites PhD Thesis 2001. Abstract | Links | BibTeX | Tags: Interferometry, Micropropulsion, System trade study @phdthesis{reichbachMicropropulsionSystemSelection2001, title = {Micropropulsion System Selection for Precision Formation Flying Satellites}, author = {Jeffrey G Reichbach}, doi = {10.2514/6.2001-3646}, year = {2001}, date = {2001-01-01}, number = {January}, abstract = {Several of NASA's upcoming scientific interferometry missions (ST-3, LISA, TPFt etc.) are pushing the limits of precision positioning of satellites. These spacecraft will require position and attitude control actuation on exceedingly small scales, which has not previously been performed. The several candidate propulsion systems for these missions include: colloid thrusters, field emission electrostatic propulsion thrusters (FEEP), pulsed plasma thrusters (PPT) and miniature cold gas thrusters. In order to assess the appropriateness of each of the candidate micropropulsion systems, a model of each is constructed. The models created are conglomerations of basic physical concepts and empirically founded relationships. Emphasis is placed on the determination of key operating parameters that are most relevant to the systems level of design. Along with models of propulsion system performance, a common set of metrics is defined to allow varied concepts to be compared fairly. High-level propulsion system design has been performed for each mission, employing the propulsion models created. These designs are evaluated according to the metrics developed and judgements about the most useful requirements for which to use the different propulsion systems are made. textcopyright 2001 by the American Institute of Aeronautics and Astronautics, Inc.}, keywords = {Interferometry, Micropropulsion, System trade study}, pubstate = {published}, tppubtype = {phdthesis} } Several of NASA's upcoming scientific interferometry missions (ST-3, LISA, TPFt etc.) are pushing the limits of precision positioning of satellites. These spacecraft will require position and attitude control actuation on exceedingly small scales, which has not previously been performed. The several candidate propulsion systems for these missions include: colloid thrusters, field emission electrostatic propulsion thrusters (FEEP), pulsed plasma thrusters (PPT) and miniature cold gas thrusters. In order to assess the appropriateness of each of the candidate micropropulsion systems, a model of each is constructed. The models created are conglomerations of basic physical concepts and empirically founded relationships. Emphasis is placed on the determination of key operating parameters that are most relevant to the systems level of design. Along with models of propulsion system performance, a common set of metrics is defined to allow varied concepts to be compared fairly. High-level propulsion system design has been performed for each mission, employing the propulsion models created. These designs are evaluated according to the metrics developed and judgements about the most useful requirements for which to use the different propulsion systems are made. textcopyright 2001 by the American Institute of Aeronautics and Astronautics, Inc. |
Schweighart, Samuel A Development and Analysis of a High Fidelity Linearized J2 Model for Satellite Formation Flying PhD Thesis 2001. Abstract | Links | BibTeX | Tags: @phdthesis{schweighartDevelopmentAnalysisHigh2001, title = {Development and Analysis of a High Fidelity Linearized J2 Model for Satellite Formation Flying}, author = {Samuel A Schweighart}, doi = {10.2514/6.2001-4744}, year = {2001}, date = {2001-01-01}, abstract = {With the recent flurry of research on satellite formation flying, a need has become apparent for a set of linearized equations of relative motion that capture the effect of the J2 geopotential disturbance force. Typically, Hill's linearized equations of relative motion have been used for this analysis, but they fail to capture the effect of the J2 disturbance force on a satellite cluster. In this paper, a new set of constant coefficient, linearized differential equations of motion is derived. These equations are similar in form to Hill's equations, but they capture the effects of the J2 disturbance force. A numerical simulator is employed to check the fidelity of the equations. It is shown that with the appropriate initial conditions, the new lin earized equations of motion have periodic errors (on the order of centimeters) that do not grow in time. The new linearized equations of motion also allow for insight into the effects of the J2 disturbance on a satellite cluster. This includes 'tumbling', the period of the relative orbit, and satellite separation due to differential J2 effects. Overall, a new high fidelity set of linearized equations are produced that are well suited to model satellite relative motion in the presence of the J2 disturbance force. textcopyright 2001 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } With the recent flurry of research on satellite formation flying, a need has become apparent for a set of linearized equations of relative motion that capture the effect of the J2 geopotential disturbance force. Typically, Hill's linearized equations of relative motion have been used for this analysis, but they fail to capture the effect of the J2 disturbance force on a satellite cluster. In this paper, a new set of constant coefficient, linearized differential equations of motion is derived. These equations are similar in form to Hill's equations, but they capture the effects of the J2 disturbance force. A numerical simulator is employed to check the fidelity of the equations. It is shown that with the appropriate initial conditions, the new lin earized equations of motion have periodic errors (on the order of centimeters) that do not grow in time. The new linearized equations of motion also allow for insight into the effects of the J2 disturbance on a satellite cluster. This includes 'tumbling', the period of the relative orbit, and satellite separation due to differential J2 effects. Overall, a new high fidelity set of linearized equations are produced that are well suited to model satellite relative motion in the presence of the J2 disturbance force. textcopyright 2001 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. |
Szabo, James Joseph Fully Kinetic Numerical Modeling of a Plasma Thruster PhD Thesis 2001. Abstract | Links | BibTeX | Tags: Szabo:PhD2001 @phdthesis{szaboFullyKineticNumerical2001, title = {Fully Kinetic Numerical Modeling of a Plasma Thruster}, author = {James Joseph Szabo}, doi = {10.1017/S0263034600182163}, year = {2001}, date = {2001-01-01}, volume = {Doctor of}, number = {1991}, abstract = {A Hall effect plasma thruster with conductive acceleration channel walls was numerically modeled using 2D3V Particle-in-Cell (PIC) and Monte-Carlo Collision (MCC) methodologies. Electron, ion, and neutral dynamics were treated kinetically on the electron time scale to study transport, instabilities, and the electron energy distribution function. Axisymmetric R-Z coordinates were used with a non-orthogonal variable mesh to account for important small-scale plasma structures and a complex physical geometry. Electric field and sheath structures were treated self-consistently. Conductive channel walls were allowed to float electrically. The simulation included, via MCC, elastic and inelastic electron-neutral collisions, ion-neutral scattering and charge exchange collisions, and Coulomb collisions. The latter were also treated through a Langevin (stochastic) differential equation for the particle trajectories in velocity space. Ion-electron recombination was modeled at the boundaries, and neutrals were recycled into the flow. The cathode was modeled indirectly by injecting electrons at a rate which preserved quasineutrality. Anomalous diffusion was included through an equivalent scattering frequency. Free space permittivity was increased to allow a coarser grid and longer time-step. A method for changing the ion to electron mass ratio and retrieving physical results was developed and used throughout. Results were compared with theory, experiments. Gradients and anisotropy in electron temperature were observed. Non-Maxwellian electron energy distribution functions were observed. The thruster was numerically redesigned; substantial performance benefits were predicted.}, keywords = {Szabo:PhD2001}, pubstate = {published}, tppubtype = {phdthesis} } A Hall effect plasma thruster with conductive acceleration channel walls was numerically modeled using 2D3V Particle-in-Cell (PIC) and Monte-Carlo Collision (MCC) methodologies. Electron, ion, and neutral dynamics were treated kinetically on the electron time scale to study transport, instabilities, and the electron energy distribution function. Axisymmetric R-Z coordinates were used with a non-orthogonal variable mesh to account for important small-scale plasma structures and a complex physical geometry. Electric field and sheath structures were treated self-consistently. Conductive channel walls were allowed to float electrically. The simulation included, via MCC, elastic and inelastic electron-neutral collisions, ion-neutral scattering and charge exchange collisions, and Coulomb collisions. The latter were also treated through a Langevin (stochastic) differential equation for the particle trajectories in velocity space. Ion-electron recombination was modeled at the boundaries, and neutrals were recycled into the flow. The cathode was modeled indirectly by injecting electrons at a rate which preserved quasineutrality. Anomalous diffusion was included through an equivalent scattering frequency. Free space permittivity was increased to allow a coarser grid and longer time-step. A method for changing the ion to electron mass ratio and retrieving physical results was developed and used throughout. Results were compared with theory, experiments. Gradients and anisotropy in electron temperature were observed. Non-Maxwellian electron energy distribution functions were observed. The thruster was numerically redesigned; substantial performance benefits were predicted. |
Uebelhart, Scott Alan Conditioning, Reduction, and Disturbance Analysis of Large Order Integrated Models for Space-Based Telescopes PhD Thesis 2001. @phdthesis{Uebelhart, title = {Conditioning, Reduction, and Disturbance Analysis of Large Order Integrated Models for Space-Based Telescopes}, author = {Scott Alan Uebelhart}, year = {2001}, date = {2001-01-01}, keywords = {★}, pubstate = {published}, tppubtype = {phdthesis} } |
Yung, J H Gain Scheduling for Geometrically Nonlinear Flexible Space Structures PhD Thesis 2001. @phdthesis{Yung2001, title = {Gain Scheduling for Geometrically Nonlinear Flexible Space Structures}, author = {J H Yung}, year = {2001}, date = {2001-01-01}, abstract = {A gain-scheduling approach for the control of geometrically nonlinear structures is developed. The objective is to improve performance over current linear design techniques that are applied to the same control problem. The approach is applicable to a variety of structures that have complex dynamics with slow variations such as flexible robotic arms and space structures with gimballing solar arrays. The modeling approach is motivated by the lack of in situ test data available for design of 0-g controllers. A Linear Fractional form allows the nonlinear and uncertain aspects of the structure to be modeled independently. The geometric nonlinearity is modeled using a feedback description of structural coupling. The uncertainty model is based on a physical parameter description, so that an experimentally identified 1-g parametric uncertainty model can be extrapolated to 0-g. The control approach is motivated by the success of linear control design synthesis and analysis techniques for space structures. Graphical heuristics for linear control design using Linear Quadratic Gaussian (LQG) and Sensitivity Weighted LQG techniques are introduced. A procedure to realize reduced-order gain-scheduled controllers from a family of linear state-space controllers is developed. A nonlinear analysis framework suitable for the slow variations of geometrically nonlinear structures is also presented. The realization procedure and nonlinear analysis is combined with the graphical linear design heuristics to form an iterative gain scheduled design process. The complete gain scheduling approach is applied to the MIT/MACE-II experiment flown on the International Space Station. Gain scheduled controller designs are shown to provide improved performance and robustness over a Multiple Model linear controllerdesign.}, keywords = {★}, pubstate = {published}, tppubtype = {phdthesis} } A gain-scheduling approach for the control of geometrically nonlinear structures is developed. The objective is to improve performance over current linear design techniques that are applied to the same control problem. The approach is applicable to a variety of structures that have complex dynamics with slow variations such as flexible robotic arms and space structures with gimballing solar arrays. The modeling approach is motivated by the lack of in situ test data available for design of 0-g controllers. A Linear Fractional form allows the nonlinear and uncertain aspects of the structure to be modeled independently. The geometric nonlinearity is modeled using a feedback description of structural coupling. The uncertainty model is based on a physical parameter description, so that an experimentally identified 1-g parametric uncertainty model can be extrapolated to 0-g. The control approach is motivated by the success of linear control design synthesis and analysis techniques for space structures. Graphical heuristics for linear control design using Linear Quadratic Gaussian (LQG) and Sensitivity Weighted LQG techniques are introduced. A procedure to realize reduced-order gain-scheduled controllers from a family of linear state-space controllers is developed. A nonlinear analysis framework suitable for the slow variations of geometrically nonlinear structures is also presented. The realization procedure and nonlinear analysis is combined with the graphical linear design heuristics to form an iterative gain scheduled design process. The complete gain scheduling approach is applied to the MIT/MACE-II experiment flown on the International Space Station. Gain scheduled controller designs are shown to provide improved performance and robustness over a Multiple Model linear controllerdesign. |
Andringa, Jason M A Systems Study on How to Dispose of Fleets of Small Satellites PhD Thesis 2001. Abstract | Links | BibTeX | Tags: @phdthesis{andringaSystemsStudyHow2001, title = {A Systems Study on How to Dispose of Fleets of Small Satellites}, author = {Jason M Andringa}, doi = {10.2514/6.2001-4741}, year = {2001}, date = {2001-01-01}, number = {February}, abstract = {A systems study was conducted to determine the most mass-efficient method of achieving spacecraft disposal. The focus of the study was on disposal by atmospheric reentry of constellations of small microsatellites in low earth orbit. Policy, tracking limitations, storage orbits, and natural orbit decay are important considerations with regards to spacecraft disposal. Various chemical and electrical propulsive technologies can be compared against tethers and ballistic coefficient altering techniques to determine the most mass-efficient method for disposal of spacecraft by atmospheric reentry within one year. It was determined that tethers and ballistic-coefficient altering methods are indeed the most efficient method of achieving atmospheric reentry of spacecraft within a certain range of altitude and mass. Tethers are the most mass-efficient method of spacecraft disposal for large satellites while decreasing the ballistic coefficient by deploying a balloon around the spacecraft or deploying a drag parachute is the most mass-efficient method for small spacecraft with a low initial altitude. The development of more advanced propulsion systems will be necessary to deorbit small spacecraft at higher LEO initial altitudes. textcopyright 2001 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } A systems study was conducted to determine the most mass-efficient method of achieving spacecraft disposal. The focus of the study was on disposal by atmospheric reentry of constellations of small microsatellites in low earth orbit. Policy, tracking limitations, storage orbits, and natural orbit decay are important considerations with regards to spacecraft disposal. Various chemical and electrical propulsive technologies can be compared against tethers and ballistic coefficient altering techniques to determine the most mass-efficient method for disposal of spacecraft by atmospheric reentry within one year. It was determined that tethers and ballistic-coefficient altering methods are indeed the most efficient method of achieving atmospheric reentry of spacecraft within a certain range of altitude and mass. Tethers are the most mass-efficient method of spacecraft disposal for large satellites while decreasing the ballistic coefficient by deploying a balloon around the spacecraft or deploying a drag parachute is the most mass-efficient method for small spacecraft with a low initial altitude. The development of more advanced propulsion systems will be necessary to deorbit small spacecraft at higher LEO initial altitudes. textcopyright 2001 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. |
Clawson, Alissa Naomi CAPTURING THE IMPACT OF MODEL ERROR ON STRUCTURAL DYNAMIC By PhD Thesis 2001. BibTeX | Tags: @phdthesis{Clawson2001, title = {CAPTURING THE IMPACT OF MODEL ERROR ON STRUCTURAL DYNAMIC By}, author = {Alissa Naomi Clawson}, year = {2001}, date = {2001-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Elias, Laila Mireille A Structurally Coupled Disturbance Analysis Method Using Dynamic Mass Measurement Techniques, with Application to Spacecraft-Reaction Wheel Systems PhD Thesis 2001. BibTeX | Tags: @phdthesis{eliasStructurallyCoupledDisturbance2001, title = {A Structurally Coupled Disturbance Analysis Method Using Dynamic Mass Measurement Techniques, with Application to Spacecraft-Reaction Wheel Systems}, author = {Laila Mireille Elias}, year = {2001}, date = {2001-01-01}, number = {March}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Chen, Allen; Saenz-Otero, Alvar; Hilstad, Mark; Miller, David Development of formation flight and docking algorithms using the SPHERES testbed Journal Article 2001. BibTeX | Tags: @article{chen2001development, title = {Development of formation flight and docking algorithms using the SPHERES testbed}, author = {Allen Chen and Alvar Saenz-Otero and Mark Hilstad and David Miller}, year = {2001}, date = {2001-01-01}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Miller, David Using the shuttle, Mir and ISS for operating micro-gravity engineering research laboratories Inproceedings AIAA Space 2001 Conference and Exposition, pp. 4648, 2001. BibTeX | Tags: @inproceedings{miller2001using, title = {Using the shuttle, Mir and ISS for operating micro-gravity engineering research laboratories}, author = {David Miller}, year = {2001}, date = {2001-01-01}, booktitle = {AIAA Space 2001 Conference and Exposition}, pages = {4648}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Fernando, Luis A Microfabricated Colloid Thruster Array PhD Thesis 2001. BibTeX | Tags: @phdthesis{Fernando2001, title = {A Microfabricated Colloid Thruster Array}, author = {Luis Fernando}, year = {2001}, date = {2001-01-01}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Kim, Y A; McManus, H L Analysis of Thermal Creak Induced Dynamics of Space Structures PhD Thesis 2001, ISSN: 02734508. @phdthesis{kimAnalysisThermalCreak2001, title = {Analysis of Thermal Creak Induced Dynamics of Space Structures}, author = {Y A Kim and H L McManus}, issn = {02734508}, year = {2001}, date = {2001-01-01}, volume = {2}, number = {November}, abstract = {A general framework for thermal creak modeling is presented. A model of a single degree of freedom system with thermal creak is first developed. The creak model captures the thermoelastic response and the nonlinear friction behavior. The nonlinear response of the creak element and the ensuing dynamic response are investigated. Key parameters that govern the responses are identified. The necessary condition for thermal creak, the profile of the creak response and the creak frequency are determined. The dynamic responses are parametrically studied to qualitatively understand the range of behaviors. Using the creak model, a procedure for thermal creak analysis of a space structure is established. To illustrate the procedure and the capabilities of the model, a deployable truss is analyzed. The data obtained from a thermal creak dynamics experiment on the deployable truss are correlated to the analysis results.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } A general framework for thermal creak modeling is presented. A model of a single degree of freedom system with thermal creak is first developed. The creak model captures the thermoelastic response and the nonlinear friction behavior. The nonlinear response of the creak element and the ensuing dynamic response are investigated. Key parameters that govern the responses are identified. The necessary condition for thermal creak, the profile of the creak response and the creak frequency are determined. The dynamic responses are parametrically studied to qualitatively understand the range of behaviors. Using the creak model, a procedure for thermal creak analysis of a space structure is established. To illustrate the procedure and the capabilities of the model, a deployable truss is analyzed. The data obtained from a thermal creak dynamics experiment on the deployable truss are correlated to the analysis results. |
Lamassoure, Elisabeth S A Framework to Account for Flexibility in Modeling the Value of On-Orbit Servicing for Space Systems PhD Thesis 2001. @phdthesis{lamassoureFrameworkAccountFlexibility2001, title = {A Framework to Account for Flexibility in Modeling the Value of On-Orbit Servicing for Space Systems}, author = {Elisabeth S Lamassoure}, year = {2001}, date = {2001-01-01}, number = {June}, abstract = {The traditional method for maintenance of space systems consists in building reliable satellites through redundancy and replacing them in case of failure, or whenever an upgrade is necessary. On-orbit servicing could change this paradigm. What would be the missions for which servicing would be most interesting, and what price would they be willing to pay for the capability to be serviced? The answer to these questions would provide valuable guidelines as to which servicing technologies to develop, and at what cost. Assuming that the technologies enabling automated servicing are available, traditional metrics and models are first proposed to systematically evaluate servicing cost-e.ectiveness within a representative trade space of serviceable missions and servicing infrastructures. It is shown that though it can capture some elements of cost-e.ectiveness, the traditional approach tends to underestimate the value of servicing and demonstrate cost advantages smaller than the cost uncertainty. This issue is solved by then proposing a new approach to on-orbit servicing. First, the intrinsic value of servicing is studied separately from its cost. Furthermore, a first framework to evaluate the flexibility provided by on-orbit servicing to space systems is developed. This framework is used to define models of the value of servicing for two families of space systems faced with di.erent types of uncertainty: commercial systems with uncertain market and military missions with dynamic requirements. For commercial missions with uncertain market, modeling servicing as an option on life extension shows that space systems should not systematically be designed for the longest possible lifetime. Instead, the optimal design life decreases with increasing uncertainty. The maximum servicing price that would make servicing economically interesting is evaluated as a function of uncertainty and the value of flexibility is illustrated on two current examples. For military missions, a small number of satellites with the option to maneuver is considered as an alternative to global coverage for flexibility with respect to contingency location. It is shown that while this alternative has little value in the case of a low Earth orbit radar constellation, it has interesting potential for geostationary communication satellites. 3}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } The traditional method for maintenance of space systems consists in building reliable satellites through redundancy and replacing them in case of failure, or whenever an upgrade is necessary. On-orbit servicing could change this paradigm. What would be the missions for which servicing would be most interesting, and what price would they be willing to pay for the capability to be serviced? The answer to these questions would provide valuable guidelines as to which servicing technologies to develop, and at what cost. Assuming that the technologies enabling automated servicing are available, traditional metrics and models are first proposed to systematically evaluate servicing cost-e.ectiveness within a representative trade space of serviceable missions and servicing infrastructures. It is shown that though it can capture some elements of cost-e.ectiveness, the traditional approach tends to underestimate the value of servicing and demonstrate cost advantages smaller than the cost uncertainty. This issue is solved by then proposing a new approach to on-orbit servicing. First, the intrinsic value of servicing is studied separately from its cost. Furthermore, a first framework to evaluate the flexibility provided by on-orbit servicing to space systems is developed. This framework is used to define models of the value of servicing for two families of space systems faced with di.erent types of uncertainty: commercial systems with uncertain market and military missions with dynamic requirements. For commercial missions with uncertain market, modeling servicing as an option on life extension shows that space systems should not systematically be designed for the longest possible lifetime. Instead, the optimal design life decreases with increasing uncertainty. The maximum servicing price that would make servicing economically interesting is evaluated as a function of uncertainty and the value of flexibility is illustrated on two current examples. For military missions, a small number of satellites with the option to maneuver is considered as an alternative to global coverage for flexibility with respect to contingency location. It is shown that while this alternative has little value in the case of a low Earth orbit radar constellation, it has interesting potential for geostationary communication satellites. 3 |
2000 |
Mallory, G J W Development and Experimental Validation of Direct Controller Tuning for Spaceborne Telescopes PhD Thesis 2000. BibTeX | Tags: @phdthesis{malloryDevelopmentExperimentalValidation2000, title = {Development and Experimental Validation of Direct Controller Tuning for Spaceborne Telescopes}, author = {G J W Mallory}, year = {2000}, date = {2000-01-01}, number = {April}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } |
Jilla, Cyrus D; Miller, David W; Sedwick, Raymond J Application of multidisciplinary design optimization techniques to distributed satellite systems Journal Article Journal of Spacecraft and Rockets, 37 (4), pp. 481–490, 2000. BibTeX | Tags: @article{jilla2000application, title = {Application of multidisciplinary design optimization techniques to distributed satellite systems}, author = {Cyrus D Jilla and David W Miller and Raymond J Sedwick}, year = {2000}, date = {2000-01-01}, journal = {Journal of Spacecraft and Rockets}, volume = {37}, number = {4}, pages = {481--490}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Mallory, Gregory J W; Miller, David W Decentralized state estimation for flexible space structures Journal Article Journal of Guidance, Control, and Dynamics, 23 (4), pp. 665–672, 2000. BibTeX | Tags: @article{w2000decentralized, title = {Decentralized state estimation for flexible space structures}, author = {Gregory J W. Mallory and David W Miller}, year = {2000}, date = {2000-01-01}, journal = {Journal of Guidance, Control, and Dynamics}, volume = {23}, number = {4}, pages = {665--672}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Mallory, Gregory J; Saenz-Otero, Alvar; Miller, David W The Origins Testbed: capturing the dynamics and control of future space-based telescopes Journal Article Optical Engineering, 39 (6), pp. 1665–1677, 2000. BibTeX | Tags: @article{mallory2000origins, title = {The Origins Testbed: capturing the dynamics and control of future space-based telescopes}, author = {Gregory J Mallory and Alvar Saenz-Otero and David W Miller}, year = {2000}, date = {2000-01-01}, journal = {Optical Engineering}, volume = {39}, number = {6}, pages = {1665--1677}, publisher = {International Society for Optics and Photonics}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Saenz-Otero, Alvar The SPHERES Satellite Formation Flight Testbed: Design and Initial Control PhD Thesis 2000. @phdthesis{Otero2000, title = {The SPHERES Satellite Formation Flight Testbed: Design and Initial Control}, author = {Alvar {Saenz-Otero}}, year = {2000}, date = {2000-01-01}, keywords = {★}, pubstate = {published}, tppubtype = {phdthesis} } |
Bourgault, Frédéric Model Uncertainty and Performance Analysis for Precision Controlled Space Structures PhD Thesis 2000. @phdthesis{bourgaultModelUncertaintyPerformance2000, title = {Model Uncertainty and Performance Analysis for Precision Controlled Space Structures}, author = {Frédéric Bourgault}, year = {2000}, date = {2000-01-01}, number = {December}, abstract = {The purpose of this thesis is to provide confidence for the designer that a concept of a future space-based telescope will meet its very stringent requirements. More specifically, our goal is to predict the amount of uncertainty in the performance prediction made through out the design process. Also, given a statistical database for structural uncertainty, the methodology presented will establish the probability of success of a particular architecture. The traditional design process starts by evaluating and comparing the performance of dif- ferent concepts by using simplified structural and disturbance models. As the process progresses the different solutions are evaluated and the most promising concept is retained and refined. Later on, some preliminary structural testing is performed, and the finite ele- ment model is updated to reflect the reality more accurately. Eventually, when the design process approach completion and is moving toward production, most of the structural elements have been tested, and the performance predictions of the model should converge to the actual system performance. Large flexible space structures present a problem in using this approach because they are often too flexible to support their own weight and/or too large to fit inside any laboratory facilities to be tested fully assembled. For example, it would be impractical to test the whole assembly of the International Space Station or SIM on the ground. Also, during the preliminary design phase, no test data are available to update the models. Nevertheless, even when the model is very mature and has been updated after experimental testing, a discrepancy remains between the predicted and actual performance of the system. These uncertainties are due to various sources of variability in the system: variable noises (sources and levels), testing conditions and environmental factors, assembly/reassembly, shipset, disturbance levels, and others. How then, can we have confidence that a particular concept will meet the requirements if the only tool we have are finite element models that may not be accurate? The solution is to try to estimate the range of uncertainty around our nominal model performances. Since in the early design phase no test data are available, our best bet will be to use past experience to predict the expected uncertainty range on the performances of a new design. Using sensitivity information and statistical uncertainties from the literature (i.e.: modal mass and stiffness parameters uncertainties [Hasselman & Chrostowski, 1991], as well as modal damping ratios uncertainties [Simonian, 1987]), we demonstrate with different techniques how to obtain estimates of the performance predictions uncertainty ranges. We also obtain the probability distribution function of the performance of the system and use it to deduce its ``probability of success'' (i.e. the probability that once built the actual struc- ture will satisfy the performance requirements). This last result, which can be obtained without too much computation, has a great useful potential and might become an integral design step for high performance controlled structures as it promises to help build confidence in the model predictions and could be used in the so called error budgeting phase. The techniques are demonstrated on a 2 degree-of-freedom sample case and on a more realistic system: the Space Interferometer Mission (SIM) Calssic model.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } The purpose of this thesis is to provide confidence for the designer that a concept of a future space-based telescope will meet its very stringent requirements. More specifically, our goal is to predict the amount of uncertainty in the performance prediction made through out the design process. Also, given a statistical database for structural uncertainty, the methodology presented will establish the probability of success of a particular architecture. The traditional design process starts by evaluating and comparing the performance of dif- ferent concepts by using simplified structural and disturbance models. As the process progresses the different solutions are evaluated and the most promising concept is retained and refined. Later on, some preliminary structural testing is performed, and the finite ele- ment model is updated to reflect the reality more accurately. Eventually, when the design process approach completion and is moving toward production, most of the structural elements have been tested, and the performance predictions of the model should converge to the actual system performance. Large flexible space structures present a problem in using this approach because they are often too flexible to support their own weight and/or too large to fit inside any laboratory facilities to be tested fully assembled. For example, it would be impractical to test the whole assembly of the International Space Station or SIM on the ground. Also, during the preliminary design phase, no test data are available to update the models. Nevertheless, even when the model is very mature and has been updated after experimental testing, a discrepancy remains between the predicted and actual performance of the system. These uncertainties are due to various sources of variability in the system: variable noises (sources and levels), testing conditions and environmental factors, assembly/reassembly, shipset, disturbance levels, and others. How then, can we have confidence that a particular concept will meet the requirements if the only tool we have are finite element models that may not be accurate? The solution is to try to estimate the range of uncertainty around our nominal model performances. Since in the early design phase no test data are available, our best bet will be to use past experience to predict the expected uncertainty range on the performances of a new design. Using sensitivity information and statistical uncertainties from the literature (i.e.: modal mass and stiffness parameters uncertainties [Hasselman & Chrostowski, 1991], as well as modal damping ratios uncertainties [Simonian, 1987]), we demonstrate with different techniques how to obtain estimates of the performance predictions uncertainty ranges. We also obtain the probability distribution function of the performance of the system and use it to deduce its ``probability of success'' (i.e. the probability that once built the actual struc- ture will satisfy the performance requirements). This last result, which can be obtained without too much computation, has a great useful potential and might become an integral design step for high performance controlled structures as it promises to help build confidence in the model predictions and could be used in the so called error budgeting phase. The techniques are demonstrated on a 2 degree-of-freedom sample case and on a more realistic system: the Space Interferometer Mission (SIM) Calssic model. |
Clarke, John Paul B Unidirectional Active Acoustic Control for Launch Vehicle Fairings PhD Thesis 2000. Abstract | Links | BibTeX | Tags: @phdthesis{clarkeUnidirectionalActiveAcoustic2000, title = {Unidirectional Active Acoustic Control for Launch Vehicle Fairings}, author = {John Paul B Clarke}, doi = {10.2514/6.2000-612}, year = {2000}, date = {2000-01-01}, abstract = {Large amplitude vibro-acoustic loads during launch cause 40% of first day spacecraft failures. Structural-acoustic control offers the potential of reducing these loads without increasing payload mass by actively stiffening and destiffening the structure of the fairing to reduce acoustic transmission and reflection. In this paper, two methods of structural-acoustic control for launch vehicle fairings are presented. The first method implements simultaneous transmission and reflection control on the structure. The second method implements an dcoustic power diode that allows acoustic energy to flow though the structure in only one direction. Both methods employ feedback control using only structural sensors and actuators to obtain global attenuation of the acoustic field within the fairing. This approach avoids the need for sensors and actuators near the payload, and is more effective at reducing the effect of disturbances than feed-forward control. textcopyright 1999 by the Massachusetts Institute of Technology.}, keywords = {}, pubstate = {published}, tppubtype = {phdthesis} } Large amplitude vibro-acoustic loads during launch cause 40% of first day spacecraft failures. Structural-acoustic control offers the potential of reducing these loads without increasing payload mass by actively stiffening and destiffening the structure of the fairing to reduce acoustic transmission and reflection. In this paper, two methods of structural-acoustic control for launch vehicle fairings are presented. The first method implements simultaneous transmission and reflection control on the structure. The second method implements an dcoustic power diode that allows acoustic energy to flow though the structure in only one direction. Both methods employ feedback control using only structural sensors and actuators to obtain global attenuation of the acoustic field within the fairing. This approach avoids the need for sensors and actuators near the payload, and is more effective at reducing the effect of disturbances than feed-forward control. textcopyright 1999 by the Massachusetts Institute of Technology. |