Observability-based Optical Autonomous Navigation using Starlight Angular Distance for Deep Space Exploration Cruise Phase

The cruise phase of deep-space exploration missions plays a vital role in the planetary exploration. Optical sensors are expected to facilitate autonomous spacecraft navigation during the extensive cruise phase. To improve the navigation accuracy under conditions of limited onboard resources, starlight angular distances were chosen as the navigation information resource. The minimum number of stars required for the navigation system was determined through observability matrix analysis. Then a scalar computation-based observability metric is proposed, combined with the starlight angular distance navigation principle, to overcome the high computational burden of the traditional observability analysis method. The influence of different starlight angular distances on the navigation accuracy can be analyzed using this metric. Based on this analysis, the optimal navigation method is combined with an optimal starlight angular distance selection algorithm. Simulations of the Jupiter exploration scenario demonstrate the performance enhancement of the proposed navigation scheme and the measurement noise influence on the navigation performance.