Development of Star Tracker Attitude and Position Determination System for Spacecraft Maneuvering and Docking Facility

Abstract: Attitude and position determination systems in satellites are absolutely necessary to keep the desired trajectory. A very accurate, reliable and most used sensor for attitude determination is the star tracker, which orient itself in space by observing and comparing star constellations with known star patterns. For on earth tests of movements and docking maneuvers of spacecrafts, the new Spacecraft Maneuvering and Docking (SMD) facility at the chair of Aerospace Information Technology at the University of Würzburg has been built. Air bearing systems on the space ve- hicles help to create micro gravity environment on a smooth surface and simulate an artificial space-like surrounding. A new star tracker based optical sensor for indoor application need to be developed in order to get the attitude and position of the vehicles. The main objective of this thesis is to research on feasible star tracking algorithms for the SMD facility first and later to implement a star detection software framework with new developed voting methods to give the star tracker system its fully autonomous function of attitude determination and position tracking. Furthermore, together with image processing techniques, the software framework is embedded into a controller board. This thesis proposes also a wireless network system for the facility, where all the devices on the vehicles can uniquely communicate within the same network and a devel- opment of a ground station to monitor the star tracker process has also been introduced. Multiple test results with different scenarios on position tracking and attitude determination, discussions and suggestions on improvements complete the entire thesis work.