IMU/GPS Integration for Spacecraft Navigation

Modern-day satellite navigation systems such as GPS, GALILEO, and GLONASS provide positioning capability of up to meter-level accuracy for users across the globe. However, these systems depend on weak signals vulnerable to blockage, interference, and periods of high acceleration. Hence, satellite navigation systems can perform poorly in tunnels, cities, space, and underwater. Furthermore, GNSS systems cannot accurately determine spatial orientation needed for guiding vehicles such as aircraft and rockets. To solve this problem an Inertial Measurement Unit (IMU) can be utilized in conjunction with a typical GNSS receiver via a sensor fusion algorithm to produce a coherent and redundant positioning output. The main challenge is dealing with the multitude of imperfections present in all IMUs which degrade the positioning accuracy exponentially over time. This presentation will outline the work done for an undergraduate thesis aimed at implementing an GPS/IMU integration scheme and verifying its functionality using simulated and real-world data. Furthermore, possible future additions to tailor the approach toward spacecraft navigation will be discussed while noting current limitations of the system within this application.