Spacecraft Formation Flying

Author: Kyle Alfriend
Publisher: Elsevier
ISBN: 0080559654
Release Date: 2009-11-16
Genre: Technology & Engineering

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

Dynamics of Natural and Artificial Celestial Bodies

Author: Halina Pretka-Ziomek
Publisher: Springer Science & Business Media
ISBN: 9789401713276
Release Date: 2013-11-11
Genre: Science

This volume contains papers presented at the US/European Celestial Mecha nics Workshop organized by the Astronomical Observatory of Adam Mickiewicz University in Poznan, Poland and held in Poznan, from 3 to 7 July 2000. The purpose of the workshop was to identify future research in celestial mech anics and encourage collaboration among scientists from eastem and westem coun tries. There was a full program of invited and contributed presentations on selected subjects and each day ended with a discussion period on a general subject in celestial mechanics. The discussion topics and the leaders were: Resonances and Chaos-A. Morbidelli; Artificial Satellite Orbits-K. T. Alfriend; Near Earth Ob jects - K. Muinonen; Small Solar System Bodies - I. Williams; and Summary - P. K. Seidelmann. The goal of the discussions was to identify what we did not know and how we might further our knowledge. The size of the meeting and the language differences somewhat limited the real discussion, but, due to the excellence of the different discussion leaders, each of these sessions was very interesting and productive. Celestial Mechanics and Astrometry are both small fields within the general subject of Astronomy. There is also an overlap and relationship between these fields and Astrodynamics. The amount of interaction depends on the interest and efforts of individual scientists.

Continuing Kepler s Quest

Author: Committee for the Assessment of the U.S. Air Force's Astrodynamic Standards
Publisher: National Academies Press
ISBN: 9780309261425
Release Date: 2012-09-06
Genre: Science

In February 2009, the commercial communications satellite Iridium 33 collided with the Russian military communications satellite Cosmos 2251. The collision, which was not the first recorded between two satellites in orbit--but the most recent and alarming--produced thousands of pieces of debris, only a small percentage of which could be tracked by sensors located around the world. In early 2007, China tested a kinetic anti-satellite weapon against one of its own satellites, which also generated substantial amounts of space debris. These collisions highlighted the importance of maintaining accurate knowledge, and the associated uncertainty, of the orbit of each object in space. These data are needed to predict close approaches of space objects and to compute the probability of collision so that owners/operators can decide whether or not to make a collision avoidance maneuver by a spacecraft with such capability. The space object catalog currently contains more than 20,000 objects, and when the planned space fence radar becomes operational this number is expected to exceed 100,000. A key task is to determine if objects might come closer to each other, an event known as "conjunction," and the probability that they might collide. The U.S. Air Force is the primary U.S. government organization tasked with maintaining the space object catalog and data on all space objects. This is a complicated task, involving collecting data from a multitude of different sensors-many of which were not specifically designed to track orbiting objects-and fusing the tracking data along with other data, such as data from atmospheric models, to provide predictions of where objects will be in the future. The Committee for the Assessment of the U.S. Air Force's Astrodynamic Standards collected data and heard from numerous people involved in developing and maintaining the current astrodynamics standards for the Air Force Space Command (AFSPC), as well as representatives of the user community, such as NASA and commercial satellite owners and operators. Preventing collisions of space objects, regardless of their ownership, is in the national security interested of the United States. Continuing Kepler's Quest makes recommendations to the AFSPC in order for it to create and expand research programs, design and develop hardware and software, as well as determine which organizations to work with to achieve its goals.

Summary of the Workshop to Identify Gaps and Possible Directions for NASA s Meteoroid and Orbital Debris Programs

Author: Division on Engineering and Physical Sciences
Publisher: National Academies Press
ISBN: 9780309215152
Release Date: 2011-08-25
Genre: Science

A Summary of the Workshop to Identify the Gaps and Possible Directions for NASA's Meteoroid and Orbital Debris Programs summarizes the two-day workshop held on March 9-10, 2011, where various stakeholders presented diverse perspectives on matters concerning NASA Micrometeoroid and Orbital Debris (MMOD) programs, NASA mission operators, the role and relationships of NASA MMOD programs to other federal agencies, MMOD and the commercial industry, and orbital debris retrieval and removal. The report assesses NASA's existing efforts, policies, and organizations with regard to orbital debris and micrometeoroids by creating advisory dialogue on potential opportunities for program enhancement and maintenance practices.

Protecting the Space Shuttle from Meteoroids and Orbital Debris

Author: Committee on Space Shuttle Meteoroid/Debris Risk Management
Publisher: National Academies Press
ISBN: 9780309059886
Release Date: 1997-12-09
Genre: Science

The space shuttle orbiter has already been struck many times by small meteoroids and orbital debris, but it has not been damaged severely. There is a real risk, however, that a meteoroid or debris impact could one day force the crew to abort a mission or might result in loss of life or loss of the shuttle itself. Protecting the Space Shuttle from Meteoroids and Orbital Debris assesses the magnitude of the problem and suggests changes that the National Aeronautics and Space Administration can make to reduce the risk to the shuttle and its crew. December

Review of the Future of the U S Aerospace Infrastructure and Aerospace Engineering Disciplines to Meet the Needs of the Air Force and the Department of Defense

Author: Air Force Science and Technology Board
Publisher: National Academies Press
ISBN: 9780309076067
Release Date: 2001-09-27
Genre: Technology & Engineering

The Principal Deputy to the Assistant Secretary of the Air Force for Acquisition requested that the National Research Council (NRC) review the Air Force's planned acquisition programs to determine if, given its scale, the highly talented scientific, technical, and engineering personnel base could be maintained, to identify issues affecting the engineering and science work force, and to identify issues affecting the aerospace industry's leadership in technology development, innovation, and product quality, as well as its ability to support Air Force missions.

Linearized Orbit Covariance Generation and Propagation Analysis Via Simple Monte Carlo Simulations Preprint

ISBN: OCLC:713225746
Release Date: 2010

Monte Carlo simulations are used to explore how well covariance represents orbit state estimation and prediction errors when fitting to normally distributed, zero mean error observation data. The covariance is generated as a product of a least-squares differential corrector, which estimates the state in either Cartesian coordinates or mean equinoctial elements, and propagated using linearized dynamics. Radar range and angles observations of a LEO satellite are generated for either a single two-minute radar pass or catalog-class scenario. State error distributions at the estimation epoch and after propagation are analyzed in Cartesian, equinoctial, or curvilinear coordinates. Results show that the covariance is representative of the state error distribution at the estimation epoch for all state representations; however, the Cartesian representation of the covariance rapidly fails to represent the error distribution when propagated away from epoch due to the linear nature of the comparison coordinate system, not the linearization of the dynamics used in the covariance propagation. Analysis demonstrates that dynamic nonlinearity ultimately drives the error distribution to be non- Gaussian in element space despite the fact that sample distribution second moment terms appear to remain consistent with the propagated covariance. Lastly, the results show the importance of using as much precision as possible when dealing with ill-conditioned covariance matrices.