运载火箭伺服机构单点失效分析技术及其应用

摘要

In order to solve the problem of insufficient identification and control for Single Point Failure ( SPF) in complex space products , a SPF analysis method and its application in servo-mech-anisms in launch vehicles were introduced .In top layer, a servo-mechanism was decomposed to 3 circuits in series , namely , hydraulic power , servo control , and loading .Each circuit was further de-composed to 4 sub circuits in series, namely, basic function, mechanical connection, electrical con-nection, and seals.In each sub circuit, the Reliability Block Diagram (RBD) was plotted and SPFs were identified .This method could be seen as a new combination of skills of the top-down approach from Fault Tree Analysis ( FTA) and the RBD graphical reasoning from Failure Mode Effects Analy-sis (FMEA).Another merit is that it extends the traditional functional fault analysis to auxiliaries which were easily ignored .The method has been applied in China ’ s manned Rendezvous and Docking missions and can serve as a reference for both rookies and veteran engineers .%针对航天复杂产品单点失效模式辨识和控制不充分的问题，介绍了一种运载火箭伺服机构单点失效分析方法。该方法将伺服机构按功能划分为能源、控制和负载力传递回路，每个回路再划分4个子回路，即基本功能子回路、机械连接子回路、电气连接子回路和密封子回路；再根据每个子回路的可靠性框图，判别单点失效环节。研究表明，此方法具备故障树（ FTA）的自顶向下的分析路径和故障模式影响分析（ FMEA ）中的可靠性框图的判别逻辑，且重点考虑了传统分析中易忽视的连接附件，适用于复杂机电产品的单点失效分析。此方法已经在执行我国载人交会对接任务中得到应用，对于工程人员和年轻员工的培训也有借鉴价值和指导作用。