Document Type : Original Article


Islamic Azad University



In this article, a complete model including cross-coupling of azimuth and elevation axes, the effect of axis friction, non-perpendicularity and imbalance of axes was implemented for the platform with two degrees of freedom. Since this model includes 3 loops of current, stability and tracking from the inside to the outside, it was necessary to design a suitable controller for each loop separately from the inside to the outside after linearizing the obtained model. Also, due to the presence of two channels, azimuth and elevation, it was necessary to repeat and design 3 controllers for both channels separately. Since the purpose of this article is to compare the performance of different controllers, PID, Fuzzy, Fuzzy PID and Fuzzy self-tuning controllers for both channels and all loops, their design and performance in time and frequency domains were analyzed. At the end, relative advantages of each controller according to different parameters of the system were presented in a comparative table.


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