Investigation of the star tracker algorithms and kalman filter integration

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Havacılık ve Uzay Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2019

Öğrenci: SELVA SARGIN GÜÇLÜ

Danışman: İLKAY YAVRUCUK

Özet:

This research outlines the investigation of star tracker algorithms and Kalman Filter implementation of star tracker aided INS. In the first chapter, the usage areas of the star tracker sensor was investigated. The purposes to use this sensor were also included. Furthermore, the sensor architecture and algorithms were examined. In the second chapter, the three main steps of the star tracker algorithms were investigated. First of all, literature survey about centroiding algorithms was done and two of them were examined in detail. Then, the literature about star matching algorithms was searched. Liebe’s triangle method and Astrometry.net’s quad method were investigated in detail. Finally, the research about the attitude determination algorithms was made. The studies made about three of them which are SVD, Triad and Quest methods were shown. In the last chapter, the results of an Extended Kalman Filter implementation of star tracker aided INS were demonstrated. For this implementation, a high altitude aircraft was chosen because star tracker sensor gives more accurate results in high altitudes. To simulate a high altitude aircraft, X-15 aircraft simulation was used in the Airlib library of Simulink. Assumptions were made about the accuracies of the star tracker sensor and INS according to the sensors that can be used in the high altitude aircrafts. Moreover, the simulation architecture of the Kalman Filter implementation, which makes attitude correction, was investigated.