Download or read book Reconfigurable Satellite Constellations for Mobile Target Tracking written by Sarah Jo Morgan and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current storm monitoring satellites offer unsatisfactory coverage of ongoing storms, either obtaining low spatial resolution, persistent coverage or high spatial resolution coverage with low temporal sampling. A reconfigurable constellation of satellites (ReCon) offers a way to augment these data sources with higher resolution coverage and improved temporal sampling. A ReCon can respond dynamically to different objectives throughout its mission lifetime, offering a more responsive, adaptable alternative to traditional Earth-observing satellite constellations. In the ReCon concept of operations, the constellation is nominally positioned to obtain global coverage. If an event of interest occurs at a particular latitude and longitude location, satellites can be maneuvered to obtain more frequent accesses of this target than otherwise achieved in the nominal configuration. While this architecture has been primarily explored with static ground targets in mind, for more dynamic events of interest, such as hurricanes, an additional layer of responsiveness can be added. A method of mobile target tracking through planning a series of low-thrust maneuvers holds promise. This method has been shown to improve the coverage characteristics of a single satellite in a hurricane case study when compared to a non-maneuvering satellite. This thesis explores and expands upon this concept, reviewing the existing work and applying an alternative approach. Throughout this thesis, procedures for adaptive reconfigurable maneuver planning are laid out and used for two hurricane case studies. This more flexible approach finds solutions for a single satellite case study observing Typhoon Megi using around 2 m/s delta-V, in comparison to similarly performing solutions previously found of around 13.5 m/s delta-V. The inclusion of an optimizer in maneuver planning enhances the prior work, exploring a continuous design space of possible maneuver options. This reveals alternative solutions and a more complete view of the entire design space. This optimization approach also allows a future user to explore the objectives of increased storm access time, closer flyovers, and total delta-V cost of maneuvers. For example, in a single satellite maneuvering case, total target access time can be doubled in comparison to a non-maneuvering case with the use of only around 2.5 m/s delta-V. Overall, this approach has resulted in the exploration of key tradeoffs between these objectives. For example, increased access time or closer passes each come at the cost of increased delta-V requirements; solutions that provide the same total access time require greater delta-V to achieve closer passes and vice versa. When considering the inclusion of multiple maneuvering satellites, diminishing returns of maneuverability are observed, with greater natural accesses occurring with a greater number of satellites in the constellation. Additionally, the concept of executing this method in real time with uncertain targets based upon hurricane forecasts is explored. This reveals the need to incorporate robustness into this optimization. Finally, the prospect of executing this theoretical concept with a ReCon demonstrator is evaluated, including taking into account potential errors in maneuver planning.

Download or read book Reconfigurable Satellite Constellations for Geo spatially Adaptive Earth Observation Missions written by Sung Wook Paek and published by . This book was released on 2012 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: Continuously increasing demand for Earth observation in atmospheric research, disaster monitoring, and intelligence, surveillance and reconnaissance (ISR) has been met by responsive architectures such as unmanned aerial systems (UAS) or artificial satellites. Space-based architectures can provide non-dominated design solutions on the utility-cost curve compared to alternate architectures through the use of two approaches: (1) reducing satellite manufacturing and launch costs and (2) introducing reconfigurability to the satellite constellations. Reconfigurable constellations (ReCons) enable fast responses to access targets of interest while providing global monitoring capability from space. The wide-area coverage and fast responses provided ReCon can complement high-resolution imagery provided by UAS. A newly proposed ReCon framework improves the model fidelity of previous approaches by utilizing Satellite Tool Kit (STK) simulations and Earth observation mission databases. This thesis investigates the design and optimization of ReCon in low Earth orbits. A multidisciplinary simulation model is developed, to which optimization techniques are applied for both single-objective and multi-objective problems. In addition to the optimized baseline ReCon design, its variants are also considered as case studies. Future work will potentially co-optimize ReCon and UAS-like systems.

Download or read book Expanded Tradespace Analysis and Operational Considerations for Reconfigurable Satellite Constellations written by Alexandra Nicole Straub and published by . This book was released on 2020 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earth observation (EO) satellites provide helpful imagery to a variety of applications ranging from weather monitoring to agricultural support. Disaster response imaging is an essential but difficult application for EO to support. Reconfigurable satellite constellations (ReCon) provide a flexible solution to the challenge of quickly providing imagery of unknown locations. ReCon leverages the natural shift of ground tracks due to the disparity between the Earth’s rotation and the period of an orbit to maneuver a constellation into repeating ground track (RGT) orbits. This maneuvering strategy relies on altitude changes to vary an orbit’s ascending node and mean anomaly, which both dictate the location of satellite’s ground track. Altitude changes require significantly less fuel than plane changes. Using ReCon allows for smaller constellations to provide high-performance imagery for disaster response for a lower cost. This work explores additional trades for consideration when developing ReCon designs. The following explores satellite image scheduling techniques to further the efficacy of an Earth observation constellation. The scheduler incorporates agile satellites to add imaging targets outside of the satellite’s nadir field of view. The ability for a satellite to slew to off-nadir targets is incredibly important when leveraging RGTs. Another design trade considered for ReCon is the propulsion system incorporated on the satellites. Performance and cost trades invoked when using electrical propulsion instead of chemical propulsion are presented within the ReCon framework. This work presents recommendations and future considerations to inform future designers. An investigation into the potential use of staged and responsive launch options further explores flexible options. Using alternative launch strategies allows a program to leverage dropping launch costs and adapt to uncertain imagery demand. The use of flexible options for EO satellite constellation design is vital in low Earth orbit as satellite technology improves, and space becomes a more crowded domain.

Download or read book Reconfigurable Circuits and Technologies for Smart Millimeter Wave Systems written by Philippe Ferrari and published by . This book was released on 2022-05-25 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the theory, modeling, and design of tunable mm-wave circuits and systems using CMOS, RF MEMS, and microwave liquid crystals.

Download or read book Mission Design Implementation of Satellite Constellations written by Jozef C. van der Ha and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: The papers contained in this Volume of Proceedings have been collected from an international Workshop entitled 'Mission Design and Implementation of Satellite Constellations' which was held in Toulouse, France, in November 1997. This Workshop represented the first international gathering of the specialists in this currently very active field of research activity. The initiative to organise a Workshop around this theme was conceived during the Congress of the International Astronautical Federation (IAF) in Beijing, China, in October 1996. On that occasion, the IAF explored concepts and possibilities for the conduct of small specialist Workshops and Symposia of current interest. Topical, interesting, and focused themes in the general field of space technology (both theories and applications) will be selected for these Symposia. They aim at offering a dedicated forum at international level for specialists and experts to exchange their views and experiences on recent and future developments within the selected theme. These specialist Workshops and Symposia supplement the comprehensive annual IAF Congresses which cover all aspects of space technology and draw a correspondingly diverse audience.

Download or read book General Framework for the Reconfiguration of Satellite Constellations written by Matthew Phillip Ferringer and published by . This book was released on 2009 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optimization and Valuation of Recongurable Satellite Constellations Under Uncertainty written by Robert S. Legge (Jr.) and published by . This book was released on 2014 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Space-based persistent surveillance provides decision makers with information necessary to effectively respond to both natural and man-made crises. This thesis investigates a reconfigurable constellation strategy that utilizes on-demand, maneuverable satellites to provide focused regional coverage with short revisit times at greatly decreased cost when compared to traditional static satellite constellations. The thesis develops and demonstrates a general framework to guide the design and optimization of recongurable satellite constellations specifically tailored to stakeholder objectives while considering requirement uncertainty. The framework is novel in that it avoids many of the assumptions and simplifications of past research by: 1. explicitly considering uncertainty in future operating conditions; 2. concurrently optimizing constellation pattern design, satellite design, and operations design; and, 3. investigating layered and asymmetric patterns. The framework consists of three elements: a detailed simulation model to compute constellation performance and cost for a variety of architectures and patterns, Monte Carlo simulation to determine how well each design performs under uncertain future conditions, and a parallel multi-objective evolutionary algorithm developed from the [epsilon]-NSGA-II genetic algorithm to nd designs that maximize performance while simultaneously minimizing cost. Additionally, a new performance metric is developed to measure directly how well a design meets desired temporal and spatial sampling requirements and a decision model and optimal assignment process is developed to determine how to employ the option of reconfigurability to respond to specific regional events. The framework was used to perform 85 optimization runs selected to compare the cost-effectiveness of several constellation architectures over varied operating conditions and coverage requirements. All optimization runs were performed in less than three months, demonstrating that parallel computing coupled with sophisticated optimization routines enable rapid spiral development of satellite constellations. Results show that recongurable constellations cost 20 to 70% less than similarly performing static constellations for the scenarios studied. The cost savings grows with increasingly demanding coverage requirements. Results from optimizing a fully asymmetric constellation pattern led to two the development of new 'quasi'-asymmetric patterns that were found to significantly outperform symmetric patterns for providing discontinuous coverage. Additionally, results show that the sun-synchronous and rapid launch architectures are the least cost-eective approaches.

Download or read book Optimization of Satellite Constellation Reconfiguration written by Uriel Scialom and published by . This book was released on 2003 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhancing the Economics of Satellite Constellations Via Staged Deployment and Orbital Reconfiguration written by Mathieu Chaize and published by . This book was released on 2003 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Science Abstracts written by and published by . This book was released on 1995 with total page 1360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spacecraft Formation Flying written by Kyle Alfriend and published by Elsevier. This book was released on 2009-11-16 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: Space agencies are now realizing that much of what has previously been achieved using hugely complex and costly single platform projects—large unmanned and manned satellites (including the present International Space Station)—can be replaced by a number of smaller satellites networked together. The key challenge of this approach, namely ensuring the proper formation flying of multiple craft, is the topic of this second volume in Elsevier's Astrodynamics Series, Spacecraft Formation Flying: Dynamics, control and navigation. In this unique text, authors Alfriend et al. provide a coherent discussion of spacecraft relative motion, both in the unperturbed and perturbed settings, explain the main control approaches for regulating relative satellite dynamics, using both impulsive and continuous maneuvers, and present the main constituents required for relative navigation. The early chapters provide a foundation upon which later discussions are built, making this a complete, standalone offering. Intended for graduate students, professors and academic researchers in the fields of aerospace and mechanical engineering, mathematics, astronomy and astrophysics, Spacecraft Formation Flying is a technical yet accessible, forward-thinking guide to this critical area of astrodynamics. - The first book dedicated to spacecraft formation flying, written by leading researchers and professors in the field - Develops the theory from an astrodynamical viewpoint, emphasizing modeling, control and navigation of formation flying satellites on Earth orbits - Examples used to illustrate the main developments, with a sample simulation of a formation flying mission included to illustrate high fidelity modeling, control and relative navigation

Download or read book Handbook of Small Satellites written by Joseph N. Pelton and published by Springer. This book was released on 2020-09-13 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past decade, the field of small satellites has expanded the space industry in a powerful way. Hundreds, indeed thousands, of these innovative and highly cost-efficient satellites are now being launched from Earth to establish low-cost space systems. These smallsats are engaged in experiments and prototype testing, communications services, data relay, internet access, remote sensing, defense and security related services, and more. Some of these systems are quite small and are simple student experiments, while others in commercial constellations are employing state-of-the-art technologies to deliver fast and accurate services. This handbook provides a comprehensive overview of this exciting new field. It covers the technology, applications and services, design and manufacture, launch arrangements, ground systems, and economic and regulatory arrangements surrounding small satellites. The diversity of approach in recent years has allowed for rapid innovation and economic breakthroughs to proceed at a pace that seems only to be speeding up. In this reference work, readers will find information pertaining to all aspects of the small satellite industry, written by a host of international experts in the field.

Download or read book Internetworking and Computing Over Satellite Networks written by Yongguang Zhang and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: The emphasis of this text is on data networking, internetworking and distributed computing issues. The material surveys recent work in the area of satellite networks, introduces certain state-of-the-art technologies, and presents recent research results in these areas.

Download or read book Defense Against the Dark Arts in Space written by Todd Harrison and published by Rowman & Littlefield. This book was released on 2021-10-20 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proliferation of counterspace weapons across the globe often calls into question what can be done to best protect satellites from attack. This analysis from the CSIS Aerospace Security Project addresses different methods and technologies that can be used by the United States government, and others, to deter adversaries from attack. A wide range of active and passive defenses are available to protect space systems and the ground infrastructure they depend upon from different types of threats. This report captures a range of active and passive defenses that are theoretically possible and discusses the advantages and limitations of each. A group of technical space and national security experts supported the analysis by working through several plausible scenarios that explore a range of defenses that may be needed, concepts for employing different types of defenses, and how defensive actions in space may be perceived by others. These scenarios and the findings that resulted from subsequent conversations with experts are reported in the penultimate chapter of the report. Finally, the CSIS Aerospace Security Project team offers conclusions drawn from the analysis, actionable recommendations for policymakers, and additional research topics to be explored in future work.

Download or read book Methods of Orbit Determination written by Pedro Ramon Escobal and published by . This book was released on 1978 with total page 479 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Department of Defense Authorization for Appropriations for Fiscal Year 2005 written by United States. Congress. Senate. Committee on Armed Services and published by . This book was released on 2005 with total page 1480 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Role of Small Satellites in NASA and NOAA Earth Observation Programs written by National Research Council and published by National Academies Press. This book was released on 2000-05-12 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Remote observations of Earth from space serve an extraordinarily broad range of purposes, resulting in extraordinary demands on those at the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), and elsewhere who must decide how to execute them. In research, Earth observations promise large volumes of data to a variety of disciplines with differing needs for measurement type, simultaneity, continuity, and long-term instrument stability. Operational needs, such as weather forecasting, add a distinct set of requirements for continual and highly reliable monitoring of global conditions. The Role of Small Satellites in NASA and NOAA Earth Observation Programs confronts these diverse requirements and assesses how they might be met by small satellites. In the past, the preferred architecture for most NASA and NOAA missions was a single large spacecraft platform containing a sophisticated suite of instruments. But the recognition in other areas of space research that cost-effectiveness, flexibility, and robustness may be enhanced by using small spacecraft has raised questions about this philosophy of Earth observation. For example, NASA has already abandoned its original plan for a follow-on series of major platforms in its Earth Observing System. This study finds that small spacecraft can play an important role in Earth observation programs, providing to this field some of the expected benefits that are normally associated with such programs, such as rapid development and lower individual mission cost. It also identifies some of the programmatic and technical challenges associated with a mission composed of small spacecraft, as well as reasons why more traditional, larger platforms might still be preferred. The reasonable conclusion is that a systems-level examination is required to determine the optimum architecture for a given scientific and/or operational objective. The implied new challenge is for NASA and NOAA to find intra- and interagency planning mechanisms that can achieve the most appropriate and cost-effective balance among their various requirements.