Optical navigation for small lunar spacecraft using the Basilisk astrodynamics software

Autonomy plays a crucial role in modern space missions, primarily due to factors such as the light time delay, uncertain environments, and operational costs. The existing optical devices in spacecraft systems can serve autonomous purposes, including navigation and detection. In recent years, there has been a growing interest in using small spacecraft for space exploration, as they have the advantages of being smaller, less complex, and less costly compared to conventional spacecraft. Additionally, there is a surge of interest in lunar missions driven by humanity's aspirations for Mars exploration and beyond. This interest is further fueled by decreasing costs associated with advances in technology and the involvement of private companies. Therefore, the focus of this thesis is on investigating autonomous optical navigation for orbit determination of small spacecraft in lunar missions. The study employs Basilisk, an open-source astrodynamics software, to model complex spacecraft dynamics and implement guidance navigation and control algorithms. Vizard, a sister program of Basilisk, provides the necessary space environment and images for processing. The research utilizes the Circle Transform method for image processing and the Centroid and Apparent Diameter method to determine the spacecraft's trajectory based on the processed image data. The obtained results and measurement models are used to determine the spacecraft's position and velocity using the square-root unscented Kalman filter. Lastly, a star-tracker is utilized to rotate the state vector to the desired frames. This research presents an autonomous and cost-effective optical navigation approach for lunar space missions.