Authors

• Reza Mohsenipour ¹
• Mehrzad Nasirian ²
• Abdol Reza Kashaninia ²
• Mohsen Fathi ¹

¹ Faculty of Aerospace Engineering, Sharif University of Technology, Tehran, Iran

² Faculty of Electrical Engineering, Malek Ashtar University of Technology, Tehran, Iran

Abstract

Increasing in dimensions of the satellites and using light movingstructures, causes flexibility and uncertainty in their models. Therefor to control the attitude of the satellites, should use those methods which resist against the plant’s model uncertainty and could reject the disturbance and the measurementnoise. One of these methods is the robust control. But due to the location of the poles in the dynamic equations of the satellite, the design of robust controllers faces some problems. In this paper, using aninternal feedback, the dynamic equations are changed so that the poles are located in a more proper place. And then,considering flexibility affects as uncertainty and also, uncertainty in inertia matrix of the satellite, a H_∞ controller, and finally to improve the performance, a µ-controller will be designed for the new equations. But these two controllers will be analyzed and compared for the primary equations and not for the new equations.For comparison, a classical controller is also designed forthe primary system.

Keywords

• Satellite attitude control
• Flexible
• Robust control
• Uncertainty