Space subsystems design: (navigation, control, structure and…)
Amir Labibian
Volume 17, Issue 1 , March 2024, , Pages 11-20
Abstract
IIn high resolution remote sensing satellites, meeting stability and pointing requirements are very crucial in mission’s success. In this regard, usually, very accurate gyroscopes are utilized as one of the main attitude sensors. In order to avoid decreasing attitude estimation accuracies, gyroscopes ...
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IIn high resolution remote sensing satellites, meeting stability and pointing requirements are very crucial in mission’s success. In this regard, usually, very accurate gyroscopes are utilized as one of the main attitude sensors. In order to avoid decreasing attitude estimation accuracies, gyroscopes data should be calibrated in appropriate time intervals. In this research an Extended Kalman Filter (EKF) based approach is investigated for gyro calibration. Therefore, at first, a model which contains main gyro parameters, namely, biases, scale factors and misalignments is proposed. Then, an EKF based algorithm for gyro parameters estimation is presented. Next, a Multiplicative Quaternion Extended Kalman Filter (MQEKF) which uses star sensor data as measurement is applied for attitude estimation. Finally, in order to evaluate the performance of the proposed gyro calibration method in attitude control loop, a quaternion feedback controller is implemented. The simulation results show that satellite’s stability and pointing are maintained with accuracies better than 0.005 deg/second and 0.15 deg which demonstrate the proposed method will be beneficial for missions with tight control requirements.
recognition, evaluation, and detection of space radiation
Marjan Moghanipoor; Maryam Kiani; S. Hossein Pourtakdost; Amir Labibian
Volume 12, Issue 4 , December 2019, , Pages 91-102
Abstract
Temperature sensors have recently been proposed for attitude estimation (AE) of Low-Earth satellites. However, since half of the satellite surfaces do not receive any heat flux from the Sun, conduction occurs among the satellite surfaces. In this regard, the present study has focused on the effect of ...
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Temperature sensors have recently been proposed for attitude estimation (AE) of Low-Earth satellites. However, since half of the satellite surfaces do not receive any heat flux from the Sun, conduction occurs among the satellite surfaces. In this regard, the present study has focused on the effect of surfaces’ conduction as well as inner radiation on AE using temperature sensors. The nonlinear filter of Unsceted Kalman filter is adopted for AE, and the developed model to describe temperature rates is verified using Thermal Desktop and SINDA software. Monte Carlo simulations prove positive effect of the conduction on AE performance against negative role of the inner radiation.