Survivability Assessment Of Spacecraft In External Debris Field

External debris such as spacecraft disintegration debris,rocket engine jets,etc.,pose a serious threat to in-orbit spacecraft.Evaluating the survivability of the spacecraft in external debris field,analyzing the failure state of the spacecraft and its components and estimating the protective performance of the spacecraft,helps improving the protection design.To implement the survivability assessment of spacecraft,it is required to give the quantitative analysis conclusions for survivability.There is currently no clear assessment of the situation in which orbiting spacecraft are impacted by external debris.This article studies the method of spacecraft survivability assessment under the threat of external debris.Based on the physical characteristics of debris field,the vulnerability of spacecraft components and the systemic risk transmission,the method of the qualitative and quantitative analysis of spacecraft survivability is completed.At the same time,the key problems of spacecraft survivability assessment in external debris field are clarified and corresponding solutions are given.Spacecraft component-level survivability is achieved through component impact sensitivity analysis,vulnerability analysis,and component survival probability calculations.Sensitivity calculations in external debris field use a spacecraft sensitivity analysis method based on spherical projection.The simulation analysis results show that the formula method has high efficiency when performing sensitivity analysis,and the finite method is adaptable.Vulnerability analysis includes failure analysis and penetration analysis.By counting the failure states of the various surfaces of the component,the survival probability of the component can be calculated.Spacecraft system-level survivability assessment includes quantitative analysis and qualitative analysis of system survivability.Quantitative analysis of system survivability can use fault-tree analysis method,Monte Carlo assessment method,and simple assessment methods.Studies have shown that the fault tree method is most suitable when considering computational efficiency and accuracy of results.The Monte Carlo method is the most widely used,and the simple evaluation method is the most convenient under certain conditions.The qualitative analysis of system survivability is based on quantitative results,which characterize the threat of component failure to the system through relative importance.The effects of the physical properties of the fragment source end velocity,the source distance of the debris,the average mass of the debris and the mass distribution of the debris on the survivability of the spacecraft are studied,and the physical properties of the debris field and the survivability of the spacecraft are obtained.A preliminary understanding of the relationship.This article designs a method for evaluating the survivability of spacecraft in external debris field,which can complete the spacecraft survivability assessment.At the same time,a comparative analysis of the accuracy,computational efficiency and applicability of various algorithms was completed.The research results of this article have certain academic research significance and have application value in engineering.