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Book Some Notes on Attitude Control of Earth Satellite Vehicles

Download or read book Some Notes on Attitude Control of Earth Satellite Vehicles written by Warren Gillespie and published by . This book was released on 1959 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Satellite Attitude Control Utilizing the Earth s Magnetic Field

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).

Book Precision Magnetic Attitude Control of Spinning Spacecraft

Download or read book Precision Magnetic Attitude Control of Spinning Spacecraft written by John A. Sorensen and published by . This book was released on 1969 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Attitude Dynamics and Control of Satellites with Fluid Ring Actuators

Download or read book Attitude Dynamics and Control of Satellites with Fluid Ring Actuators written by Nona Abolfathi Nobari and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Successful mission of a satellite depends on maintaining a fixed orientation with respect to the Earth. However, the attitude angles of a satellite can be perturbed because of various natural disturbance sources, such as the Earth's gravity gradient, solar radiation pressure, and the Earth's magnetic field. Modeling the attitude dynamics and developing a controller to stabilize the attitude motion are quite important steps in the design of satellites. Although several actuators exist to control the attitude motion, a novel type considered in the thesis, shows promise of producing a high torque to mass ratio. This potential justifies the in-depth study reported. The novel actuator in question consists of a ring containing fluid, whose flow is regulated by a pump. The control torque is produced due to the variation of the angular velocity of the fluid. In this thesis, first, a redundant actuator system composed of four fluid rings in a pyramidal configuration is studied. The dynamical model of the system is developed for a satellite travelling either in a circular or an elliptical orbit. The dynamical analysis of this system leads to an underdetermined system of nonlinear differential equations, whose solution without considering the control input (the torque produced by the pump pressure) shows that the fluid rings can damp out the attitude disturbances of a satellite in a circular orbit and the roll-yaw disturbances in an elliptical orbit. However, this passive damping effect is fairly slow; an active controller is hence designed in the next step. The effect of the failure of one fluid ring on the performance of the attitude control subsystem (ACS) of a satellite is also studied. It is observed that even in the case of failure of one fluid ring, the satellite can be stabilized by slight modification of the active controller. Later, a sliding mode controller is designed to cope with the uncertainties existing in the fluid model and in other parameters of the system. Although the results achieved are quite satisfactory, the chattering that exists in the steady response of the system is not desirable; hence a switching controller consisting of a sliding mode and a PID control law is designed to eliminate this chattering effect. Next, the theoretical results obtained are validated by conducting several experiments. Although the experimental results confirm the theory developed in this thesis, the large torque-to-mass ratio expected is revealed to be only possible at the cost of a quite high input voltage to the pumps regulating the flow. Therefore, two novel applications of fluid rings are proposed: as an actuator for spin stabilized satellites, or as an auxiliary actuator in satellites with magnetic torquers.Using fluid rings in spin stabilized satellites is proposed in the thesis, as an alternative to the commonly used micro-thrusters. Here, two fluid rings are mounted on the satellite while their axes of symmetry are aligned with the roll and yaw axes. To examine the feasibility and performance, a dynamical model of this spinning satellite with two fluid rings is developed. A controller is then designed to stabilize the attitude motion of this satellite.The second novel actuator system developed here consists in using fluid rings as complementary actuators in satellites with two magnetic torquers. The dynamical model is formulated, and a controller is designed to investigate the performance of this system. The simulation of the system without the fluid ring shows that the satellite attitude can be stabilized by using only two magnetic torquers, however, slowly. Upon adding the active fluid ring actuator to the system, the stabilization time is reduced by a factor of 10. The failure of the fluid ring and each magnetic torquer is also studied." --

Book Magnetic Attitude and Spin Control of the Small Scientific Satellite S3 A

Download or read book Magnetic Attitude and Spin Control of the Small Scientific Satellite S3 A written by Thomas W. Flatley and published by . This book was released on 1970 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic attitude and spin control of small scientific satellite.

Book Magnetic Attitude Control of Near Earth Spinning Satellites

Download or read book Magnetic Attitude Control of Near Earth Spinning Satellites written by Indian Space Research Organisation and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Attitude Orientation Control for a Spinning Satellite

Download or read book Attitude Orientation Control for a Spinning Satellite written by Gerald Frost and published by . This book was released on 1991 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Department of the Air Force, Headquarters Space Systems Division, and the National Aeronautics and Space Administration (NASA) are currently involved in litigation with Hughes Aircraft Company over the alleged infringement of the "Williams patent," which describes a method for attitude control of a spin-stabilized vehicle. This Note summarizes pre-1960 RAND work on this subject and presents information obtained from RAND personnel who are knowledgeable in this area. The Note also reviews the TIROS II magnetic torque attitude control method

Book Torques and Attitude Sensing in Earth Satellites

Download or read book Torques and Attitude Sensing in Earth Satellites written by S. Fred Singer and published by Elsevier. This book was released on 2012-12-02 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applied Mathematics and Mechanics, Volume 7: Torques and Attitude Sensing in Earth Satellites focuses on the possible torques that can affect the angular momentum of an Earth satellite. This book provides an understanding of the environment in which a satellite operates. Organized into 16 chapters, this volume starts with an overview of the application of force-free motion to space programs. This text then discusses the torque effects of a gravitational field, particularly with its gradient. Other chapters consider a particular method of gravity-gradient stabilization that utilizes a passive device to damp librations and thereby attain a vertical orientation. This book discusses as well the effects of the geomagnetic field on the angular motion of a satellite. The reader is also introduced to the method of magnetic attitude control employed in the Tiros satellite. The final chapter deals with the problem of horizon sensing, which is important for satellites requiring Earth stabilization. Astrophysicists will find this book useful.

Book A Study of Attitude Stability of a Symmetrical Satellite in a Circular Orbit

Download or read book A Study of Attitude Stability of a Symmetrical Satellite in a Circular Orbit written by Hsien-tsan Wang and published by . This book was released on 1967 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model for analytical study of the attitude stability of an orbiting satellite consists of a rigid body whose mass center is constrained to move at constant speed in a circular path about the center of an inverse-square force field. The body is assumed to have one axis of inertial symmetry. It is of primary interest here to determine whether the attitude of this symmetric axis is stable in its various equilibrium positions. The stability depends upon two parameters: the ratio of spin velocity about the symmetry axis to orbital angular velocity, and the ratio of the two moments of inertia of the satellite. The equations of motion which govern the deviations of the symmetry axis from its equilibrium configuration are nonlinear in nature. When linearized, the equations show instability in some regions, but everywhere else, the linear approximation is a "critical case" in which the roots of the characteristic equation all have zero real part. When complete nonlinear equations are investigated by means of the direct method of Lyapunov, some region can be specified as Lyapunov stable by using the Hamiltonian function as a Lyapunov function, while there remains a sizeable region where the stability has not been determined, as shown in papers by Pringle and Likins, When equations which are approximated by third and fifth powers are investigated by a series of transformations following Malkin's approach, it is found that if there is instability in the remainder of plane where no conclusion is yet available, it is very weak.

Book A Method for Controlling the Attitude of a Satellite Using the Earth s Magnetic Field

Download or read book A Method for Controlling the Attitude of a Satellite Using the Earth s Magnetic Field written by Wilfred Joseph Minkus and published by . This book was released on 1964 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report investigates a means of controlling the attitude of a satellite in a circular orbit about the earth by the torque due to the interaction between the earth's magnetic field and the magnetic moments produced by currents in three orthogonal coils aboard the satellite. This system has the advantage over more conventional ones in that no mass is expended in the control process. It is designed to rotate the satellite about its longitudinal axis in a minimum amount of time while limiting the deviation of this axis from the local normal to the earth. The analysis is limited to the period during which the satellite's attitude is being changed by magnetically produced torques. When these torques are not applied, gravity gradient effects act as a restoring force to align the longitudinal axis with the local normal to the earth. The method is applicable to a satellite with symmetry such that the moment of inertia about its longitudinal axis is much smaller than those about body-fixed axes lying in a plane perpendicular to it and whose moments of inertia about axes in this plane are approximately equal. The model of the earth's magnetic field that is used is a dipole with its poles located at the observed geographical positions. The control system is developed to be applicable to the general type of satellite indicated above and to all orbits except those passing close to the magnetic poles. It is then applied to a particular satellite and type of orbit of interest to RADC. (Author).

Book Fast Satellite Attitude Maneuver and Control

Download or read book Fast Satellite Attitude Maneuver and Control written by Dong Ye and published by Elsevier. This book was released on 2022-08-03 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fast Satellite Attitude Maneuver and Control introduces the concept of agile satellites and corresponding fast maneuver attitude control systems, systematically and comprehensively presenting recent research results of fast maneuver attitude control for agile satellites by using advanced nonlinear control techniques. This reference book focuses on modeling and attitude control, considering different actuator combinations, actuator installation deviation, actuator fault, and flexible appendage coupling effect for agile satellites. The book provides a unified platform for understanding and applicability of agile satellites fast maneuverer and stabilization control for different purposes. It will be an excellent resource for researchers working on spacecraft design, nonlinear control systems, vehicle systems and complex control systems. Unifies existing and emerging concepts concerning nonlinear control theory, fault tolerant, and attitude control for agile satellites Provides a series of the latest results, including, but not limited to, fast maneuverer and stabilization control, hybrid actuator control, nonlinear attitude control, fault tolerant control, and active vibration suppression towards agile satellites Comprehensively captures recent advances of theory, technological aspects and applications of fast maneuverer and stabilization control in agile satellites Addresses research problems in each chapter, along with numerical and simulation results that reflect engineering practice and demonstrate the focus of developed analysis and synthesis approaches Contains comprehensive, up-to-date references, which play an indicative role for further study

Book Magnetic Attitude Control of Microsatellites In Geocentric Orbits

Download or read book Magnetic Attitude Control of Microsatellites In Geocentric Orbits written by Jiten Dutia and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Attitude Prediction of Spin Stabilized Low Altitude Artificial Earth Satellites Employing Magnetic Attitude Control

Download or read book Attitude Prediction of Spin Stabilized Low Altitude Artificial Earth Satellites Employing Magnetic Attitude Control written by Joel Norman Minsker and published by . This book was released on 1964 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: