@Article{SilvaGaSaKuZaPa:2022:RaPaFi,
               author = "Silva, William R. and Garcia, Roberta V. and Santilli, G. and 
                         Kuga, H{\'e}lio Koiti and Zanardi, M. Cec{\'{\i}}lia F. P. S. 
                         and Pardal, Paula C. P. M.",
          affiliation = "{Universidade de Bras{\'{\i}}lia (UnB)} and {Universidade de 
                         S{\~a}o Paulo (USP)} and {Universidade de Bras{\'{\i}}lia 
                         (UnB)} and {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade Estadual Paulista (UNESP)} and {Universidade de 
                         S{\~a}o Paulo (USP)}",
                title = "Rao-Blackwellized Particle Filter for the CBERS-4 attitude and 
                         gyros bias estimation",
              journal = "Acta Astronautica",
                 year = "2022",
               volume = "193",
               number = "679-690",
                month = "Apr.",
             keywords = "Artificial satellites, Attitude estimation, CBERS-4, Gyros bias, 
                         Rao-Blackwellized Particle Filter, Unscented Kalman Filter.",
             abstract = "The Rao-Blackwellized Particle Filter (RaoBPF) and the Unscented 
                         Kalman Filter (UKF) were applied in this work to attitude and 
                         gyros bias estimation using simulated orbit and attitude 
                         measurement data for CBERS-4 (China Brazil Earth Resources 
                         Satellite 4) recently in operation. CBERS-4 was launched in 2014, 
                         controlled and operated in shifts by China (Xi'an Control Center) 
                         and Brazil (Satellite Control Center). Its orbit is 
                         heliosynchronous with an inclination of 98.504 degrees, a 
                         semi-major axis of 7148.865 km, eccentricity 1.1×10\−3, 
                         crossing equador line at 10h30min in a descending direction with 
                         perigee frozen at 90 degrees, which establishes a commitment 
                         relationship between a satisfactory amount of solar irradiance, 
                         contrast between targets, and the presence of clouds. This 
                         configuration provides global coverage every 26 days. The real 
                         orbit and attitude measurements were provided by the Satellite 
                         Control Center of the National Institute for Space Research (CCS - 
                         INPE) from September 1st, 2015. The dynamic attitude model is 
                         described by quaternions. The available attitude sensors are two 
                         Digital Sun Sensors (DSS), two Infrared Earth Sensor (IRES) and a 
                         triad of mechanical gyroscopes. 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. The gyros furnish the angular measurements in the 
                         body frame reference system. Gyros provide direct incremental 
                         angles or angular velocities; however, they present several 
                         sources of error, and the drift is the most troublesome. Such 
                         drifts yield along time an accumulation of errors which must be 
                         accounted in the attitude determination process. The RaoBPF 
                         estimation method used to attitude and gyros bias estimation is a 
                         technique that exploits the state space structure in order to 
                         reduce the number of particles, decreasing the processing time, 
                         avoiding the computational effort common to the standard particle 
                         filter. The logical extension of the RaoBPF provides a more 
                         general model that can be divided into purely non-linear and 
                         conditionally linear-Gaussian aspects, which explores this 
                         structure, marginalizing the conditional linear parts and 
                         estimating them using exact filters, such as the Extended Kalman 
                         Filter (EKF). The results show that it is possible to achieve 
                         precision in determining attitudes within the prescribed 
                         requirements using the RaoBPF, with lower computational cost when 
                         compared to the standard particle filter and its branches, in 
                         addition to have competitive results such as the UKF.",
                  doi = "10.1016/j.actaastro.2021.07.049",
                  url = "http://dx.doi.org/10.1016/j.actaastro.2021.07.049",
                 issn = "0094-5765",
             language = "en",
           targetfile = "Silva_2022_rao.pdf",
        urlaccessdate = "11 maio 2024"
}