International Journal of Electrical and Computer Engineering (IJECE) Vol.
No.
June 2014, pp.
ISSN: 2088-8708
Design of Fuzzy Optimized Controller for Satellite Attitude Control by Two State actuator to reduce Limit Cycle based on Takagi-Sugeno Method Sobutyeh Rezanezhad Departement of Control Engineering.
Science and Research Branch.
Islamic Azad University.
Boroujerd.
Iran
Article Info
ABSTRACT
Article history:
In this paper, an algorithm was presented to control the satellite attitude in orbit in order to reduce the fuel consumption and increase longevity of Because of proper operation and simplicity, fuzzy controller was used to save fuel and analyze the uncertainty and nonlinearities of satellite control system.
The presented control algorithm has a high level of reliability facing unwanted disturbances considering the satellite limitations.
The controller was designed based on Takagi-Sugeno satellite dynamic model, a powerful tool for modeling nonlinear systems.
Inherent chattering related to on-off controller produces limit cycles with low frequency amplitude.
This increases the system error and maximizes the satellite fuel consumption.
Particle Swarm Optimization (PSO) algorithm was used to minimize the system error.
The satellite simulation results show the high performance of fuzzy on-off controller with the presented algorithm Received Jan 4, 2014 Revised May 3, 2014 Accepted May 24, 2014 Keyword:
Satellite attitude control Takagi-Sugeno model fuzzy on-off control limit cycle PSO Copyright A 2014 Institute of Advanced Engineering and Science.
All rights reserved.
Corresponding Author:
Departement of Control Engineering.
Science and Research Branch.
Islamic Azad University.
Boroujerd.
Iran Email: sobut.
e@gmail.
INTRODUCTION
The fuel saving is highly desirable in the satellite attitude control system.
Two-level on-off controllers are generally used with the thrust reaction actuator for satellite attitude control.
These controllers act very fast and are time independent.
They control the satellite attitude with or without thrust power in minimum time.
In on-off control systems, the valves operate reliably to stay open for a short time as a few The full opening of valves for a finite time changes the discrete angular velocity with the As a result, itAos impossible to obtain zero residual angular quickness.
To prevent the interaction of thrusters, a dead band is introduced between the on-off control, and the controller is shut down in this dead band region.
Thus, the controlled system reaches the equilibrium point .
with reduced velocity or increased dampness.
This generates low frequency .
nd amplitud.
limit-cycles, and dissipates the thruster Since the satellite behavior is inherently nonlinear and uncertain, itAos recommended to use nonlinear control algorithms like fuzzy logic.
This algorithm is independent of the accurate model of micro satellite.
Stein applied three multi-input single-output (MISO) fuzzy controllers to stabilize a small .
satellite in low earth orbit.
He proved that fuzzy controllers can erase the control limitations by choosing the best magnetic moment, polarity and switching times .
Satellite control system can save fuel and enhance the satellite performance.
on-off attitude control by on-off and sliding mode was investigated in reference .
One of the problems of using sliding mode controller is that it generates a great control signal due to the system uncertainty.
Fuzzy controller was used to solve this problem .
Fuzzy controller is an appropriate choice to control nonlinear systems.
Minimizing the time required for the system to reach the steady state is an important point in fuzzy controller design.
This is achieved by optimal adjustment of membership functions .
The controller investigated in reference .
needs different initial values to improve the system Journal homepage: http://iaesjournal.
com/online/index.
php/IJECE A ISSN: 2088-8708 operation and minimize the response time.
But these applications are not proper to design standard linear In this case, on-off controller is an appropriate option .
Reference .