Download or read book Attitude Estimation and Control of a Magnetically actuated Earth observing Cubesat written by Corey Miles and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Meteorix mission is a nanosatellite demonstration mission dedicated to the observation and characterization of meteors and space debris entering into the Earth's atmosphere. The scientific objectives of this mission require a high performance attitude determination and control system (ADCS). This thesis entails the development of attitude estimation and control algorithms for the Meteorix 3U cubesat. Attitude estimation and control requirements are outlined, given the mission's scientific objectives and the power needs of the satellite. A magnetometer-only multiplicative extended Kalmanfilter (MEKF) is formulated to estimate the satellite's attitude and angular velocity. Itis compared to a conventional gyro-based MEKF and uses the derivative of the magnetic field and the attitude dynamics model, in place of gyroscope measurements to update the angular velocity estimate. Results from Monte Carlo simulations show that the magnetometer-only MEKF outperforms a gyro-based MEKF in low angular velocity scenarios. A sliding mode controller is developed for attitude control using three magnetic actuators, while a single flywheel oriented in a momentum bias configuration provides gyroscopic stability. Using the attitude and angular velocity feedback from the magnetometer-only MEKF, the sliding mode control law offers better pointing accuracy than a standard proportional derivative (PD) magnetic feedback controller; it is also shown to be more robust to uncertainties and disturbances in a sensitivity study. The magnetometer-only MEKF suffers in the presence of model uncertainties such as flywheel misalignment and residual magnetic moment, and methods to improve the overall ADCSperformance are discussed"--

Download or read book A flexible attitude control system for three axis stabilized nanosatellites written by Gordon, Karsten and published by Universitätsverlag der TU Berlin. This book was released on 2018-03-15 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis investigates a new concept for the flexible design and verification of an ADCS for a nanosatellite platform. In order to investigate guidelines for the design of a flexible ADCS, observations of the satellite market and missions are recorded. Following these observations, the author formulates design criteria which serve as a reference for the conceptual design of the flexible ADCS. The research of the thesis was carried out during the development of TU Berlin's nanosatellite platform TUBiX20 and its first two missions, TechnoSat and TUBIN. TUBiX20 targets modularity, reuse and dependability as main design goals. Based on the analysis of design criteria for a flexible ADCS, these key design considerations for the TUBiX20 platform were continued for the investigations carried out in this thesis. The resulting concept implements the ADCS as a distributed system of devices complemented by a hardware-independent core application for state determination and control. Drawing on the technique of component-based software engineering, the system is partitioned into self-contained modules which implement unified interfaces. These interfaces specify the state quantity of an input or output but also its unit and coordinate system, complemented by a mathematical symbol for unambiguous documentation. The design and verification process for the TUBiX20 ADCS was also elaborated during the course of this research. The approach targets the gradual development of the subsystem from a purely virtual satellite within a closed-loop simulation to the verification of the fully integrated system on an air-bearing testbed. Finally, the concurrent realization of the investigated concept within the TechnoSat and TUBIN missions is discussed. Starting with the individual ADCS requirements, the scalability of the approach is demonstrated in three stages: from a coarse, but cost- and energy-efficient configuration to realize a technology demonstration mission with moderate requirements (TechnoSat) to a high-performance configuration to support Earth observation missions (TUBIN). Diese Dissertation untersucht ein neues Konzept zur flexiblen Entwicklung und Verifikation eines Lageregelungssystems für eine Nanosatellitenplattform. Als Grundlage für die Erarbeitung eines Leitfadens für die Entwicklung werden zunächst Beobachtung des Satellitenmarkts sowie konkreter Missionen zusammengetragen. Darauf aufbauend formuliert der Autor Entwurfskriterien für die Konzipierung eines flexiblen Lageregelungssystems. Die Dissertation wurde im Rahmen der Entwicklung der TUBiX20 Nanosatellitenplattform und ihrer ersten beiden Missionen, TechnoSat und TUBIN, an der TU Berlin durchgeführt. TUBiX20 verfolgt Modularität, Wiederverwendung und Zuverlässigkeit als Entwicklungsziele. Diese werden unter der Verwendung der vom Autor hergeleiteten Entwurfskriterien in dieser Arbeit im Kontext des Lageregelungssystems verfeinert. Das resultierende Konzept setzt dieses als verteiltes System von Geräten und einem hardware-unabhängigen Software-Kern um. Der Software-Entwurfstechnik Component-based software engineering folgend ist das System in unabhängige Module unterteilt, welche wiederum einheitliche Schnittstellen implementieren. Diese Schnittstellen spezifizieren die Zustandsgrößen für die Ein- und Ausgänge der Module inklusive Einheit, Koordinatensystem und mathematischem Symbol für eine eindeutige Darstellung. Der Entwurfs- und Verifikationsprozess für das TUBiX20 Lageregelungssystem wurde vom Autor im Rahmen der Arbeit untersucht. Hier verfolgt der Ansatz einen schrittweisen übergang von einem virtuellen Satelliten als Simulationsmodell bis hin zur Verifikation des integrierten Systems auf einem Lageregelungsteststand. Abschließend diskutiert die Arbeit die Realisierung des untersuchten Konzepts im Rahmen der Missionen TechnoSat und TUBIN. Beginnend mit den jeweiligen Anforderungen wird die Skalierbarkeit des Ansatzes in drei Stufen demonstriert: von einer groben, aber kosten- und energieeffizienten Konfiguration für eine Technologieerprobungsmission mit moderaten Anforderungen (TechnoSat) bis hin zu einer Konfiguration für hochgenaue Lageregelung als Basis für Erdbeobachtungsmissionen (TUBIN).

Download or read book Spacecraft Attitude Determination and Control written by J.R. Wertz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 877 pages. Available in PDF, EPUB and Kindle. Book excerpt: Roger D. Werking Head, Attitude Determination and Control Section National Aeronautics and Space Administration/ Goddard Space Flight Center Extensiye work has been done for many years in the areas of attitude determination, attitude prediction, and attitude control. During this time, it has been difficult to obtain reference material that provided a comprehensive overview of attitude support activities. This lack of reference material has made it difficult for those not intimately involved in attitude functions to become acquainted with the ideas and activities which are essential to understanding the various aspects of spacecraft attitude support. As a result, I felt the need for a document which could be used by a variety of persons to obtain an understanding of the work which has been done in support of spacecraft attitude objectives. It is believed that this book, prepared by the Computer Sciences Corporation under the able direction of Dr. James Wertz, provides this type of reference. This book can serve as a reference for individuals involved in mission planning, attitude determination, and attitude dynamics; an introductory textbook for stu dents and professionals starting in this field; an information source for experimen ters or others involved in spacecraft-related work who need information on spacecraft orientation and how it is determined, but who have neither the time nor the resources to pursue the varied literature on this subject; and a tool for encouraging those who could expand this discipline to do so, because much remains to be done to satisfy future needs.

Download or read book Attitude Stabilization for CubeSat written by Mohammed Chessab Mahdi and published by Cambridge Scholars Publishing. This book was released on 2018-11-14 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores CubeSat technology, and develops a nonlinear mathematical model of a spacecraft with the assumption that the satellite is a rigid body. It places emphasis on the CubeSat subsystem, orbit dynamics and perturbations, the satellite attitude dynamic and modeling, and components of attitude determination and the control subsystem. The book focuses on the attitude stabilization methods of spacecraft, and presents gravity gradient stabilization, aerodynamic stabilization, and permanent magnets stabilization as passive stabilization methods, and spin stabilization and three axis stabilization as active stabilization methods. It also discusses the need to develop a control system design, and describes the design of three controller configurations, namely the Proportional–Integral–Derivative Controller (PID), the Linear Quadratic Regulator (LQR), and the Fuzzy Logic Controller (FLC) and how they can be used to design the attitude control of CubeSat three-axis stabilization. Furthermore, it presents the design of a suitable attitude stabilization system by combining gravity gradient stabilization with magnetic torquing, and the design of magnetic coils which can be added in order to improve the accuracy of attitude stabilization. The book then investigates, simulates, and compares possible controller configurations that can be used to control the currents of magnetic coils when magnetic coils behave as the actuator of the system.

Download or read book Satellite Attitude Control Utilizing the Earth s Magnetic Field written by John S. White (writer on artificial satellites.) and published by . This book was released on 1961 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: The torque developed by the interaction of current-carrying coils with the earth's magnetic field can be used as a means of attitude control. The degree to which the attitude of a vehicle can be maintained utilizing this torque depends on the fluctuations of the magnetic field at the satellite as the satellite orbits about the earth. Due to the nature of the torque developed only two vehicle axes can be c ntinuously controlled simultaneously. With the principle described, either a two- or three-coil system can be used to control vehicle attitude about two axes. Intermittent control about three axes can be obtained. (Author).

Download or read book Fundamentals of Spacecraft Attitude Determination and Control written by F. Landis Markley and published by Springer. This book was released on 2014-05-31 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores topics that are central to the field of spacecraft attitude determination and control. The authors provide rigorous theoretical derivations of significant algorithms accompanied by a generous amount of qualitative discussions of the subject matter. The book documents the development of the important concepts and methods in a manner accessible to practicing engineers, graduate-level engineering students and applied mathematicians. It includes detailed examples from actual mission designs to help ease the transition from theory to practice and also provides prototype algorithms that are readily available on the author’s website. Subject matter includes both theoretical derivations and practical implementation of spacecraft attitude determination and control systems. It provides detailed derivations for attitude kinematics and dynamics and provides detailed description of the most widely used attitude parameterization, the quaternion. This title also provides a thorough treatise of attitude dynamics including Jacobian elliptical functions. It is the first known book to provide detailed derivations and explanations of state attitude determination and gives readers real-world examples from actual working spacecraft missions. The subject matter is chosen to fill the void of existing textbooks and treatises, especially in state and dynamics attitude determination. MATLAB code of all examples will be provided through an external website.

Download or read book Spacecraft Modeling Attitude Determination and Control written by Yaguang Yang and published by CRC Press. This book was released on 2019-02-06 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses all spacecraft attitude control-related topics: spacecraft (including attitude measurements, actuator, and disturbance torques), modeling, spacecraft attitude determination and estimation, and spacecraft attitude controls. Unlike other books addressing these topics, this book focuses on quaternion-based methods because of its many merits. The book lays a brief, but necessary background on rotation sequence representations and frequently used reference frames that form the foundation of spacecraft attitude description. It then discusses the fundamentals of attitude determination using vector measurements, various efficient (including very recently developed) attitude determination algorithms, and the instruments and methods of popular vector measurements. With available attitude measurements, attitude control designs for inertial point and nadir pointing are presented in terms of required torques which are independent of actuators in use. Given the required control torques, some actuators are not able to generate the accurate control torques, therefore, spacecraft attitude control design methods with achievable torques for these actuators (for example, magnetic torque bars and control moment gyros) are provided. Some rigorous controllability results are provided. The book also includes attitude control in some special maneuvers, such as orbital-raising, docking and rendezvous, that are normally not discussed in similar books. Almost all design methods are based on state-spaced modern control approaches, such as linear quadratic optimal control, robust pole assignment control, model predictive control, and gain scheduling control. Applications of these methods to spacecraft attitude control problems are provided. Appendices are provided for readers who are not familiar with these topics.

Download or read book Hardware and Software Implementation of a Low Power Attitude Control and Determination System for CubeSats written by Jesse Frey and published by . This book was released on 2014 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years there has been a growing interest in smaller satellites. Smaller satellites are cheaper to build and launch than larger satellites. One form factor, the CubeSat, is especially popular with universities and is a 10 cm cube. Being smaller means that the mass and power budgets are tighter and as such new ways must be developed to cope with these constraints. Traditional attitude control systems often use reaction wheels with gas thrusters which present challenges on a CubeSat. Many CubeSats use magnetic attitude control which uses the Earth's magnetic field to torque the satellite into the proper orientation. Magnetic attitude control systems fall into two main categories: active and passive. Active control is often achieved by running current through a coil to produce a dipole moment, while passive control uses the dipole moment from permanent magnets that consume no power. This thesis describes a system that uses twelve hard magnetic torquers along with a magnetometer. The torquers only consume current when their dipole moment is flipped, thereby significantly reducing power requirements compared with traditional active control. The main focus of this thesis is on the design, testing and fabrication of CubeSat hardware and software in preparation for launch.

Download or read book ADCS Spacecraft Attitude Determination and Control written by Michael Paluszek and published by Elsevier. This book was released on 2023-04-27 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: ADCS - Spacecraft Attitude Determination and Control provides a complete introduction to spacecraft control. The book covers all elements of attitude control system design, including kinematics, dynamics, orbits, disturbances, actuators, sensors, and mission operations. Essential hardware details are provided for star cameras, reaction wheels, sun sensors, and other key components. The book explores how to design a control system for a spacecraft, control theory, and actuator and sensor details. Examples are drawn from the author’s 40 years of industrial experience with spacecraft such as GGS, GPS IIR, Mars Observer, and commercial communications satellites, and includes historical background and real-life examples. Features critical details on hardware and the space environment Combines theory and ready-to-implement practical algorithms Includes MATLAB code for all examples Provides plots and figures generated with the included code

Download or read book CubeSat Attitude Control Utilizing Low power Magnetic Torquers a Magnetometer written by Donald B. Mentch and published by . This book was released on 2011 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: The CubeSat Project has lowered development time and costs associated with university satellite missions that conform to their 10 centimeter cube design specification. Providing attitude control to a spacecraft, of such small volume, with a very limited power budget has been a challenge around the world. This work describes the development of an attitude control system based on a very low-power magnetic torquer used in conjunction with a magnetometer. This will be the first flight use of this torquer which is composed of a hard magnetic material wrapped inside of a solenoid. By discharging a capacitor through the solenoid, the magnetic dipole moment of this permanent magnet can be reversed. The completed attitude control system will make the first use of the low-power magnetic torquer to arrest satellite tip-off rates. It will then make the first known use of a dual axis magnetic dipole moment bias algorithm to achieve three-axis attitude alignment. The complete system is standalone for high inclination orbits, and will align the spacecraft to within 5 degrees of ram, nadir, and local vertical, without any requirement for attitude determination. The system arrests tip-off rates of up to 5° per second (in all 3 axes) for a satellite in a 600 kilometer polar orbit expending 0.56 milliwatts of power. Once in the proper alignment, it utilizes 0.028 milliwatts to maintain it. The system will function for low inclination orbits with the addition of a gravity boom. The system utilizes the magnetometer to calculate spacecraft body rates. This is the only known use of a magnetometer to directly measure spacecraft body rates without prior knowledge of spacecraft attitude.

Download or read book Fuzzy Attitude Control of a Magnetically Actuated CubeSat written by Alex R. Walker and published by . This book was released on 2013 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: The problem of magnetic attitude control of a CubeSat is analyzed. Three controller types are examined: a Constant-Gain Simple PD controller, a Linear Constant-Gain Optimal PD controller (i.e. an LQR), and a Fuzzy Gain-Scheduled PD controller. Each subsequent controller type utilizes a more-complex design algorithm. The Simple PD controller is tuned by hand iteration, the LQR is tuned using rule-of-thumb algorithms, and the Fuzzy Gain-Scheduled PD controller is designed using a Genetic Algorithm operating on two Fuzzy Inference Systems. Though the basic structures of these three controllers are identical, the differing design processes lead to different controller performance. The use of a Genetic-Fuzzy System is of particular interest, because this demonstrates the use of an intelligent algorithm to automate the controller design process. The techniques presented herein are directly applicable to any magnetically actuated satellite that can be modeled as a rigid body, although the mass distribution, geometry, and orbit of the satellite will determine controller-specific constants.

Download or read book Small Satellites for Earth Observation written by Rainer Sandau and published by Springer Science & Business Media. This book was released on 2008-04-18 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 6th IAA Symposium on Small Satellites for Earth Observation, initiated by the International Academy of Astronautics (IAA), was again hosted by DLR, the German Aerospace Center. The participation of scientists, engineers, and managers from 24 countries reflected the high interest in the use of small satellites for dedicated missions applied to Earth observation. The contributions showed that dedicated Earth observation missions cover a wide range of very different tasks.

Download or read book Attitude Control Subsystem for the Advanced Communications Technology Satellite written by Alan W. Hewston and published by . This book was released on 1996 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fault Tolerant Attitude Estimation for Small Satellites written by Chingiz Hajiyev and published by CRC Press. This book was released on 2020-12-22 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small satellites use commercial off-the-shelf sensors and actuators for attitude determination and control (ADC) to reduce the cost. These sensors and actuators are usually not as robust as the available, more expensive, space-proven equipment. As a result, the ADC system of small satellites is more vulnerable to any fault compared to a system for larger competitors. This book aims to present useful solutions for fault tolerance in ADC systems of small satellites. The contents of the book can be divided into two categories: fault tolerant attitude filtering algorithms for small satellites and sensor calibration methods to compensate the sensor errors. MATLAB® will be used to demonstrate simulations. Presents fault tolerant attitude estimation algorithms for small satellites with an emphasis on algorithms’ practicability and applicability Incorporates fundamental knowledge about the attitude determination methods at large Discusses comprehensive information about attitude sensors for small satellites Reviews calibration algorithms for small satellite magnetometers with simulated examples Supports theory with MATLAB simulation results which can be easily understood by individuals without a comprehensive background in this field Covers up-to-date discussions for small satellite attitude systems design Dr. Chingiz Hajiyev is a professor at the Faculty of Aeronautics and Astronautics, Istanbul Technical University (Istanbul, Turkey). Dr. Halil Ersin Soken is an assistant professor at the Aerospace Engineering Department, Middle East Technical University (Ankara, Turkey).

Download or read book Satellite Attitude Control Using the Earth s Magnetic Field written by R. E. TOEPFER and published by . This book was released on 1962 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study and Development of Attitude Control and Determination Simulation Software and Control Algorithms for 3Cat 4 Mission written by Carlos Diez Garcia and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The AOCS of a spacecraft is the responsible for determining the attitude of the satellite and controlling it to reach a specific pointing state, to alloww the execution of scientific experiments on board. In the case of 3Cat-4 mission, a magnetic control system is used to align the deployable helix antenna with the Nadir vector to perform the GNSS-R and L-band radiometry experiments for Earth Observation. This task is especially complex to perform in nanosatellites due to the limitations of mass, size, and power consumption. To analyze the performance of this subsystem, facilities (Helmholtz coils, TVAC, Sun simulator) are used that try to emulate the environment in which the satellite will operate, but this is not always possible and for this reason this project has been carried out. In this project, a simulation software programmed in MATLAB has been developed to analyze the performance of the AOCS subsystem. This tool has been used to validate the design and verify the compliance with the subsystem requirements, but also to support the design phase. In addition, the simulator has been used to analyze the AOCS of the 3Cat-4 mission developed by the UPC NanoSat Lab. This document explains the physics behind each of the blocks modeled to emulate the space environment, implementing the equations that govern the orbial dynamics and attitude of the satellite and including the disturbance forces that affect a satellite in orbit LEO . In addition, the development of the attitude determination and control system, both of the hardware part (i.e. sensors and actuators) and of the estimation and control algorithms, is presented. In particular, the Optimal-REQUEST algorithm has been implemented and the control laws for the Detumbling and Nadir Pointing Mode modes, corresponding to the 3Cat-4 mission, have been developed. The results of the analysis showthe correct operation of the simulator and the compliance of the subsystem requirements of the 3Cat-4 mission. The control modes meet the objectives defined, i.e. the detumbling mode is capable to stabilize the system and reduce the angular velocity of the CubeSat below 2°/s in less than 24 hours and the Nadir Pointing mode allows to reach the pointing towards Nadir, with a maximum angular deviation of 10° and angular velocity of 0.5°/s in the X and Y axes of the satellite. On the other hand, the results show the great negative impact of the aerodynamic drag, due to the physical characteristics of the CubeSat and the orbit in which it is located, causing the control system to have to be continuously active to compensate for the disturbances and reach the desired attitude state. 2.

Download or read book CubeSat Handbook written by Chantal Cappelletti and published by Academic Press. This book was released on 2020-09-25 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: CubeSat Handbook: From Mission Design to Operations is the first book solely devoted to the design, manufacturing, and in-orbit operations of CubeSats. Beginning with an historical overview from CubeSat co-inventors Robert Twiggs and Jordi Puig-Suari, the book is divided into 6 parts with contributions from international experts in the area of small satellites and CubeSats. It covers topics such as standard interfaces, on-board & ground software, industry standards in terms of control algorithms and sub-systems, systems engineering, standards for AITV (assembly, integration, testing and validation) activities, and launch regulations. This comprehensive resource provides all the information needed for engineers and developers in industry and academia to successfully design and launch a CubeSat mission. Provides an overview on all aspects that a CubeSat developer needs to analyze during mission design and its realization Features practical examples on how to design and deal with possible issues during a CubeSat mission Covers new developments and technologies, including ThinSats and PocketQubeSats