ATTITUDE CONTROL FOR A NANO SATELLITE BY USING FUZZY AND APPROACHING INDEX SWITCHING ALGORITHM

Abstract

This paper presents a comparison between the approaching index switching algorithm (AISA) and a fuzzy controller for attitude control in a nanosatellite in 3-axes. AISA is designed to switch between two different controls based on an index value. The first controller accelerates the system to reach the desired angle. The other controller is decelerating the system before approaching the desired angle. A reaction wheel (RW) is used to provide the torque required to rotate the satellite about its axis. The purpose of the controller is to change the rotational speed of the RW so that the satellite points in the correct direction. This comparison reveals that the AISA controller is much more efficient in maneuvering and accurate in contrast to fuzzy control. The control effort is preserved by 66% compared to the fuzzy control effort. This shows that the use of this type of intelligent control system represents a significant advantage over the conventional control systems currently used for satellite attitude control.