A review of model extensions and solution methods for space orbital games

The increase in human space activities has increased space threats, such as debris and failed spacecraft, which has made space orbital game technology a critical tool for ensuring space security. Although differential game theory remains the mainstream approach for classic space orbital games, its application faces growing limitations because of nonlinear orbital dynamics, model complexity, computational intractability, and poor real-time performance in increasingly complex scenarios. To address these challenges, numerous extended orbital game models have been developed in recent years, along with new solution methods. This review provides a systematic analysis and summary of model extensions and solution methods in orbital games. First, the extension directions of space orbital games are analyzed, and five extended game models based on the basic orbital game model are summarized: the closed-loop guidance model, incomplete information model, diverse scenario game model, impulsive thrust model, and multispacecraft game model. Afterward, research achievements in solution methods, including qualitative differential games, quantitative differential games, and artificial intelligence methods, are categorized and reviewed. Finally, current challenges and potential future research directions are discussed.