Attitude Determination using Extended Kalman Filter for Elliptical Orbit Satellites

Abstract

This paper investigates the influence of eccentricity on the performance of the attitude determination and control subsystem (ACDS) pointing of passive low earth orbit (LEO) satellites stabilized by a gravity-gradient boom. The contribution of this work is two-fold. First, satellite attitude dynamics and kinematics are modeled by introducing the orbit eccentricity in the equation of motion of an LEO satellite in order to provide the best scenarios in which satellite operators can keep the nominal functionality of LEO satellites with a gravity-gradient boom. Second, a quaternion-based extended Kalman filter (EKF) is analyzed when the orbit eccentricity is considered in order to determine the influence of this disturbance on the convergence and stability of the filter. The simulations of this work are based on the real parameters of LEO satellite stabilized by gravity-gradient boom. The obtained results show that the orbit eccentricity has a big influence on the pointing system accuracy by causing micro-vibrations that affect the geocentric pointing

Keywords: Spacecraft attitude dynamics, Kalman filter, gravity gradient torque, eccentricity