Reliability Analysis And Simulation Research Of Space Articulated Deplovable Mast

As a repeated fold-unfold and lock-unlock space deployable mechanism with high precision,collapsed rate and stability, the space articulated deployable mast is utilized in various spaceexploration activities, such as deploying solar array, supporting detection equipment, and helpingto construct space station. Due to the extremely low temperature and high vacuum in the spaceenvironment, where the space mast works, the reliability of mast system is confronted with direchallenges: on the one hand, the failure modes of mast system is highly unpredictable under theinfluence of space environment; on the other hand, it is barely able to completely simulate thespace environment only through the ground test with limited condition. Hence, the reliability ofarticulated deployable mast is studied systematically from the perspective of reliability theory inthis thesis.Depending on the operating principle and structural composition of the space mast, everyfailure mode of the mast system in the space environment is detected. Then, in accordance withthe FMEA procedure, the FMEA table of the mast system is accomplished.Different reliability analysis methods by combining various theories with dynamic fault treeanalysis are measured and tested. Therefore, the dynamic fault tree analysis based onBayesian networks is determined to analyze the reliability of the space mast. In terms of FMEAtable above, a dynamic fault tree model of the mast system is established, and converted tocorresponding Bayesian networks model. Thus, the reliability degree of the mast system iscalculated by using BNT.Aiming at the working process of deployable unit, which is a part of the space mast, therelevant mechanical property is analyzed, and the mechanical models at different stages alongthe working process are built. Then, the Monte Carlo method is adopted to solve the reliabilitiesof deployable unit at different stages. Consequently, the reliability degree of the deployable unitis settled by connecting reliability models at different stages in series.Considering the extreme small sample quantity and high reliability of the space articulateddeployable mast, the counting sequential sampling method is adapted to make a test plan.According to its fundamental principle, theory, judgment standard, test method and process step, the conceptual design of the reliability test on the space mast is made by taking the samplequantity of the space mast into account.