چكيده به لاتين
The satellite formation includes the distribution of a set of satellites that interact automatically with each other to achieve the desired configuration. In terms of cost-optimization, the use of several small satellites for purposes such as atmospheric sampling, design and manufacture of extensive telecommunication coverage by multiple beams, designing different imaging structures, is more cost-effective than using a large satellite.
In this thesis, the satellites are modeled in a virtual structure architecture, and the distributed attitude control is designed for 3D imaging. For this purpose, the dynamics of the virtual structure, as well as the dynamics of the attitude of the satellites, are presented taking into account external and internal disturbances. In this regard, in order to reduce the effect of disturbances, a nonlinear observer is designed and combined in the form of feedback with the control rules. The control rules include two parts of the virtual control, in order to control the virtual structure, as well as the control rule of the attitude of each satellite in the formation. Combined control rules and disturbance observer, which are designed, have proved to be stable using the Lyapunov method. In order to control the virtual structure, PD control law has been used, and the sliding mode controller has been utilized to control each satellite in the formation. Designed control rules are also implemented by the reaction wheel actuator.
Keywords: Satellite Formation Flying, Attitude Control, Virtual Structure, Distributed Control, Nonlinear disturbance Observation, Sliding Mode Controller