Unified Model Reference Adaptive Attitude Control of a Satellite in Presence of Uncertain Parameters: Design and Implementation

In this paper, a discrete-time model reference adaptive attitude control algorithm (MRAC) will be designed based on unified approach for a three-axis stabilized satellite. In this algorithm, environmental disturbances and nonlinear dynamic terms will be estimated as a time-varying unknown parameter. In this method, nonlinear dynamic equation of satellite is rewritten as a linear model with uncertain parameters as the main novel idea. Therefore, MRAC algorithm is designed for the linear model in the presence of uncertain parameters, and then it will be applied to the nonlinear model of the satellite in presence of uncertain or unknown parameters. The proposed method is capable of simultaneous tracking and regulation. The designed algorithm will be implemented in software in the loop test bed with the use of ARM microcontroller in real time mode in order to evaluation and verification of its performance