Nonlinear Least Squares Method for Gyros Bias and Attitude Estimation Using Satellite Attitude and Orbit Toolbox for Matlab

17th Brazilian Colloquium on Orbital Dynamics

Silva, W.R.^1 ; Kuga, H.K.^1 ; Zanardi, M.C.^2

Space Mechanics and Control Division, National Institute for Space Research (INPE), Av dos Astronautas, 1758, Jd. da Granja, São José dos Campos, S.P.

CEP:12227-010, Brazil^1

Federal University of ABC (UFABC), Av. dos Estados, 5001, Bangu, Santo-André, S.P.

CEP:09210-580, Brazil^2

关键词: Attitude determination;    Attitude estimation;    China-brazil earth resources satellites;    Non-linear estimation;    Non-linear least squares;    Nonlinear functions;    Nonlinear least squares methods;    Satellite attitude and orbits;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/641/1/012005/pdf
DOI  :  10.1088/1742-6596/641/1/012005

来源: IOP

【 摘 要 】

The knowledge of the attitude determination is essential to the safety and control of the satellite and payload, and this involves approaches of nonlinear estimation techniques. Here one focuses on determining the attitude and the gyros drift of a real satellite CBERS-2 (China Brazil Earth Resources Satellite) using simulated measurements provided by propagator PROPAT Satellite Attitude and Orbit Toolbox for Matlab. The method used for the estimation was the Nonlinear Least Squares Estimation (NLSE). The attitude dynamical model is described by nonlinear equations involving the Euler angles. The attitude sensors available are two DSS (Digital Sun Sensor), two IRES (Infra-Red Earth Sensor), and one triad of mechanical gyros. The two IRES give direct measurements of roll and pitch angles with a certain level of error. The two DSS are nonlinear functions of roll, pitch, and yaw attitude angles. Gyros are very important sensors, as they provide direct incremental angles or angular velocities. However gyros present several sources of error of which the drift is the most troublesome. Results show that one can reach accuracies in attitude determination within the prescribed requirements, besides providing estimates of the gyro drifts which can be further used to enhance the gyro error model.