Adaptive Fuzzy Sliding Mode Control of Pointing Maneuvers of an Uncertain LEO Communication Satellite

Precise pointing of a Low Earth Orbit or LEO satellite is vital to maintain the antenna, gimbaled cameras, and solar panels in the correct direction. To tackle the complexities and uncertainties in the dynamics of a typical low Earth orbit (LEO) satellite equipped with a Ka-band transmitter, and to overcome the external disturbances, this study introduces an Adaptive Fuzzy Sliding Mode Control (AFSMC) approach, which is shown to be robust against uncertainties with unknown upper bounds. The control input is directly generated by applying a sliding-mode controller, in which an adaptive method is used to estimate the upper bound of the uncertainty. In contrast to traditional Sliding Mode Control (SMC), AFSMC integrates an online-estimated fuzzy controller, obviating the need for model-based linearization. The stability of the closed-loop system is rigorously ensured through Lyapunov stability analysis. Comparative simulations against Proportional-Derivative (PD) and SMC controllers highlight the AFSMC's superior pointing accuracy and reduced energy consumption, demonstrating its effectiveness.

کلیدواژه ها:

LEO satellite ، System Uncertainty ، Attitude control ، AFSMC ، Reaction wheels