Threat assessment for non-cooperative spacecraft integrating orbital dynamics and image quality

With growing on-orbit confrontation complexity, traditional threat assessment for non-cooperative approach observations struggles with subjectivity and latency. We propose a mission-completion-based framework that integrates relative orbital dynamics with optical imaging principles. Relative motion in the orbital plane is parameterized and observation modes are classified using line-of-sight (LOS) coverage and solar illumination. Innovatively, the Structural Similarity Index Measure (SSIM) serves as an objective image-quality metric under varying distance and illumination, aided by a scale-alignment (cropping) procedure to ensure consistent spatial scaling. A Unity-based simulator reproduces dynamic imaging, and threat is quantified by the time-averaged SSIM over an orbital period. Multi-scenario experiments show that the physics-based metric eliminates subjective weighting common to multi-attribute schemes while enabling rapid, interpretable assessment for autonomous optical defense and maneuvering planning.