Safety analysis and research on risk assessment model of spacecraft assembly

Spacecraft assembly plays an important role in spacecraft production process. Accidents in spacecraft assembly can cause product damage and worker injury, which delay the schedule of production and increase the manufacture cost, therefore, safety analysis and research on risk assessment model of spacecraft assembly have great significance to assuring of quality and schedule of spacecraft manufacture, as well as to reducing cost of spacecraft manufacture. International researches on spacecraft assembly safety and reliability are introduced. Relations and distinctions of safety and reliability of system are discussed further based on existing research and it is stressed that analytical contents in safety assessment of spacecraft assembly are not just confined to system function inability caused by component faults because human fault, system design, and environmental elements all can result in casualties, property damage or environmental pollution. Finally, a spacecraft assembly systematic safety analysis and quantitative risk assessment model is put forward which includes 4 steps:1) work procedures and tasks decomposition; 2)development of Safety Analysis Graph for each task; 3) development of spacecraft assembly Hazards Identification and Accident Prediction Database System; 4) development of spacecraft assembly Safety Assessment Index System. The model can be validated by the actual satellites manufactured and utilized to predict accidents of spacecraft assembly correctly.