Reşat Özgür Doruk and Erol Kocaoğlan
This paper aims to focus on the implementation of the integral back‐stepping control on the model of BILSAT – 1 satellite of the Turkish Scientific and Technological Research…
Abstract
Purpose
This paper aims to focus on the implementation of the integral back‐stepping control on the model of BILSAT – 1 satellite of the Turkish Scientific and Technological Research Council (TUBITAK).
Design/methodology/approach
The nonlinear model of the satellite is divided into three groups and the control Lyapunov function is constructed systematically. The formed closed loop system is analyzed for stability according to a recently developed stability analysis procedure and multi‐run simulations.
Findings
Since the studied model includes the dynamics of a practical reaction wheel (SSTL Type: Microwheel), the simulation results showed that the designed controllers are suitable for practical application. The torque requirement is far below the maximum torque supplied by the wheel. In addition, the system seems to be quite fast and robust against the parametric uncertainties.
Research limitations/implications
Since the control system is nonlinear, the computational complexity will be an issue in practical application. The stability analysis should be improved to have more reliable information concerning the disturbance torques. Currently this analysis is performed by multi‐run simulations. An observer or estimator may also be designed in order to compute the attitudes from the gyroscope readings.
Practical implications
The controller designed here can be implemented on the proceeding satellite projects (foregoing BILSAT projects) by TUBITAK.
Originality/value
The paper provides a satellite control application of back‐stepping using a model involving modified Rodriguez parameters and reaction wheel dynamics that is not studied in the literature.
Details
Keywords
R. Özgür Doruk and Erol Kocaoglan
The purpose of this paper is to derive a robust nonlinear attitude control law intended for practical application.
Abstract
Purpose
The purpose of this paper is to derive a robust nonlinear attitude control law intended for practical application.
Design/methodology/approach
The method of input/output feedback linearization is utilized for having a linear model and a recently developed almost disturbance decoupling (ADD) approach is adopted for designing a robust satellite attitude control (SAC) system. The kinematics of the satellite is modeled by modified Rodriguez parameters because of their continuous invertibility. The design is simulated on the model of a realistic satellite project (BILSAT‐I), which is developed by the Turkish Scientific and Technological Research Council.
Findings
The torque requirement of the operation does not exceed the maximum limit provided by the actuator. The square error levels are staying under the boundary of final global attractor, which is one of the important proofs for the successful operation of the generated ADD control law.
Originality/value
The ADD concept is investigated on SAC problem. By that way, simple control structures with known disturbance attenuation capability can be designed.