Development of control allocation methods for satellite attitude control

Elmas, Tuba Çiğdem
This thesis addresses the attitude control of satellites with similar and dissimilar actuators and control allocation methods on maneuvering. In addition, the control moment gyro (CMG) steering with gyroscopes having limited gimbal angle travel is also addressed. Full Momentum envelopes for a cluster of four CMG's are obtained in a pyramid type mounting arrangement. The envelopes when gimbal travel is limited to plus-minus 90 degree are also obtained. The steering simulations using Moore Penrose (MP) pseudo inverse as well as blended inverse are presented and success of the pre planned blended inverse steering in avoiding gimbal angle limits is demonstrated through satellite slew maneuver simulations, showing the completion of the maneuver without violating gimbal angle travel restrictions. Dissimilar actuators, CMG and magnetic torquers are used as an approach of overactuated system. Steering simulations are carried out using different steering laws for constant torque and desired satellite slew maneuver scenarios. Success of the blended inverse steering algorithm over MP pseudo inverse is also demonstrated.


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Varying missile configurations may create uncertainty for a missile control algorithm developed with linear control theory, for instance the control system performance requirements may not be satisfied anymore. Missile configuration may change during the missile design period due to variations in subsystem locations, subsystem weights and missile geometry. Likewise, burning propellant, deployment of aerodynamic surfaces and wings with varying sweep angle can be considered as in-flight missile configuration ...
Development of de-icing and anti-icing solutions for aircraft on ground and analysis of their flow instability characteristics
Körpe, Durmuş Sinan; Özgen, Serkan; Department of Aerospace Engineering (2008)
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Flight simulation and control of a helicopter
Erçin, Gülsüm Hilal; Tekinalp, Ozan; Department of Aerospace Engineering (2008)
In this thesis the development of a nonlinear simulation model of a utility helicopter and the design of its automatic flight control system is addressed. In the first part of this thesis, the nonlinear dynamic model for a full size helicopter is developed using the MATLAB/SIMULINK environment. The main rotor (composed of inflow and flapping dynamics parts), tail rotor, fuselage, vertical stabilizer, horizontal stabilizer of the helicopter are modeled in order to obtain the total forces and moments needed f...
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Yemenici, Öznur; Uzol, Oğuz; Department of Aerospace Engineering (2010)
This thesis focuses on developing and examining the capabilities of a new in-house aerodynamic analysis tool, AeroSIM+, and investigating rotor-rotor aerodynamic interactions for two helicopters, one behind the other in forward flight. AeroSIM+ is a 3-D unsteady vortex panel method potential flow solver based on a free vortex wake methodology. Validation of the results with the experimental data is performed using the Caradonna-Tung hovering rotor test case. AeroSIM+ code is improved for forward flight cond...
Citation Formats
T. Ç. Elmas, “Development of control allocation methods for satellite attitude control,” M.S. - Master of Science, Middle East Technical University, 2010.