Fuzzy control system for dual-spin satellite

number: 
575
إنجليزية
Degree: 
Author: 
Ali Muhsen Ni'ama
Supervisor: 
Dr. Mohammed Z. Al-Faiz
Dr. Mohammed J. Al-Bermani
year: 
2001
Abstract:

Many researchers used different techniques for controlling the attitude dualspin satellite such as optimal feedback, variable structure and other controllers. The essential characteristic of these controllers is dependent on the state variables or mathematical model of the satellite, the fuzzy logic controller is a new feature and original work in controlling dual-spin satellite attitude. The fuzzy logic control can be applied to linear or non-linear systems without the need to the state variables or mathematical model of the satellite, where the fuzzy controller can be evaluated and tested it in a real time system. The fuzzy logic controllers are designed for controlling three types of control functions, spin axis attitude control, payload despin control, and the vehicle nutation stabilization control for the dual-spin satellite. The dual-spin satellite for this study consists of two rigid bodies, the rotor and the platform and both of them have been modeled. The non-linear dynamic equations of the rotor and platform are derived, then these equations are linearized using a small angle maneuvers the mathematical model is introduced just for simulation and comparison between the results, where the fuzzy logic control does not need to the mathematical model. Three proposed fuzzy controllers are designed for the dual-spin satellite with appropriate membership functions, scaling factors, and rules, which made the convenient decision for these controllers. In this work, a good tracking and cross coupling cancellation performance was obtained. The time required for die out of the nutatiori angle was very short, when it compared with other works. An efficient robustness performance implementation for the attitude satellite parameter variations was obtained with a satisfactory transient response and steady state of the actual output plant for the above three type control functions.