Improved HSSE-tree method based on binary label

Because of the increase of the demand for the autonomy of spacecrafts, model-based diagnosis has been a hot research spot both at home and abroad. Computing all minimal hitting sets is a key step of model-based diagnosis. An effectively improved method of HSSE-tree called Binary-label HSSE based on HSSE-tree and combining binary labels was put forward. The improved method used binary digits to mark the real elements of the nodes, and used effectively pruning and expanding strategies, to avoid the main problem of HSSE-tree, the explosive growth of the expanded nodes and supersets along with the dimension of the problems. Additionally, computing between binary digits can avoid the traverse of every element in a node when judging whether the node is a minimal hitting set (MHS), which also contributes to the significant decrease of the run time. Simulation results show the improved method costs much less space and time than the HSSE-tree method, which provides both theoretical and applicative foundation for fault diagnosis and Real-time diagnosis of spacecraft system.