Anti-radiation Performance Evaluation Methods And Application Based On Equivalent Experiment And Data Fusion

Spacecrafts play important roles in the fields of economy,society,national defense and security.It is important to ensure their stability and reliability in orbit operation.Among the space environments,the space radiation environments are important,which could induce the abnormality and even failure of spacecraft.Efficient evaluation of spacecraft anti-radiation performance is very important to ensure the safety and reliability of spacecrafts.Because the complexity of space radiation environments and radiation damage mechanisms,anti-radiation performance evaluation faces many challenges.The existing methods of spacecraft anti-radiation performance evaluation mainly focus on ground equivalent experiment and numerical simulation.The ground equivalent experiments have high fidelity.But is difficult to simulate real space complex radiation environment and the cost is high.Although the numerical simulations are easy to implement,the fidelity are not acceptable.This thesis presents evaluation methods of spacecraft anti-radiation performance evaluation based on equivalent experiment,combination of numerical simulation with ground equivalent experiment.The main research of this thesis are as follows:(1)The equivalent experiment design method based on adaptive generalized hierarchical expectation enhancement.The ground experiment of spacecraft anti-radiation needs to simulate the real radiation environments and radiation damage effects as accuracy as possible to improve the fidelity of the experiment.At present,the equivalent conditions of ground experiments are mainly determined by experience and standards.The credibility are not assured.Therefore,the thesis propose an adaptive equivalent experiment method.At first the Bayesian optimization method is used to establish optimization model.And then,the thesis proposes an adaptive search strategy to improve the ability of the equivalent optimization model for different complexity black box functions,as well as the search efficiency.Numerical examples are given to demonstrate these methods,and the applicability of different equivalent experiment design methods are also compared.(2)Anti-radiation performance evaluation method based on multi-accuracy data fusion.At present,the charged particle radiation environments are highly uncertain.,It is difficult to achieve high-precision results of anti-radiation performance under all possible radiation environment,only through limited ground experiments.The composite Gaussian process model has been constructed for the numerical simulation data,which solves the robustness problem of the composite correlation matrix.Then,the scale modified fusion(SF)model of different accuracy experiment data such as ground test and numerical simulation,which is able to make up the shortage of high-accuracy ground experiment by numerical simulation.Finally,the thesis uses numerical examples to verify the proposed method.(3)The supplementary experiment design method based on fused Gaussian process model.It is difficult to ensure that the evaluation results meet the accuracy requirements with the given experiment data,such that supplement experiments data is often needed.According to the different scenarios of spacecraft anti radiation experiment,an improved blind Kriging model and a qualitative quantitative factor mixed Gaussian process model are constructed respectively.On this foundation,we calculate the prediction mean square deviation and prediction error to determine the best neighborhood.The MCMC algorithm is used to obtain the supplementary experiment points with the largest prediction mean square deviation.Finally,numerical examples are used to verify the effectiveness of supplementary experimental design method.(4)Kapton foils radiation resistance evaluation case application.Based on dose-depth response characteristics of Kapton foils,the thesis started ground equivalent experiment design,multi-accuracy data fusion evaluation and supplementary experiment design of Kapton foils.The results show that the model and method of this thesis proposed effectively solve the problem of insufficient accuracy in the evaluation of radiation resistance of Kapton foils.Finally,analyse the contribution of this thesis and propose research prospects.