Study of attitude control systems for satellites

Dissertant

Baraya, Imad Albir

University

University of Technology

Faculty

-

Department

Department of Control and Systems Engineering

University Country

Iraq

Degree

Master

Degree Date

1999

English Abstract

The growing need in recent years for designing systems involving interconnected rigid and flexible structures, such as the new generation of satellites with large flexible appendages has led to the appearance of a new class of modeling and control problems.

In fact, controlling the uncertain behavior of a flexible structure subject to unknown disturbances is relatively complex, which makes the fulfillment of design objectives hard to be achieved by designers.

Variable structure control has high potentials in tackling such systems with variable parameters.

This work deals with the design of attitude control systems for satellites with flexible appendages based on Variable Structure Systems (VSS) theory to improve pointing accuracy and robustness over conventional methods.

Reaction wheels are used as the control actuators.

Single axis with single mode of flexibility is considered with three different Cases : when the flexibility is not considered in the controllers1 design, when all slates of the system are to be used by the controllers (including flexible body states), and also when an observer is used to estimate the states.

Single axis with three modes of flexibility and three axis flexible models are also used in the simulation results are presented where the performances of seven variable structure controllers' algorithms are tested.

Some controllers showed satisfactory performance characteristics.

The various variable structure control laws are tested experimentally for large angle single axis rotational maneuvers of a flexible satellite.

The satellite is simulated by a cylindrical platform with flexibility effect.

The control algorithms dive the simulated system from S0°to 0° in 7 seconds.

Main Subjects

Mechanical Engineering

Topics

• Artificial satellites
• Control systems

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-306343