Evaluation Of Equipment Health Based On D-S Evidence Theory

With the rapid development of information technology,the functional structure of complex equipment is becoming more and more perfect,and the degree of automation is also increasing.As a typical complex equipment,self-propelled artillery will be affected by environment,performance and operability and other factors during training and operation,and the probability of failure is greatly increased.The traditional fault diagnosis and maintenance mode has problems of low maintenance efficiency and waste of resources,which is difficult to meet the maintenance needs of self-propelled guns.In order to improve the equipment integrity,reliability and maintainability of self-propelled artillery,it is necessary to effectively assess the health status of self-propelled artillery,and the main research work of the thesis has the following points:(1)Healthiness assessment techniques are studied.Aiming at the problems of low maintenance efficiency and lack of guarantee resources of the current fault diagnosis mode by analyzing the characteristics of self-propelled artillery,the healthiness assessment technology is proposed to be applied to a self-propelled artillery system.The health assessment theory and related assessment methods are introduced,and the method based on D-S evidence theory is used to assess the self-propelled gun for decision making in view of the abnormal and incomplete assessment data.(2)An improvement method of evidence theory based on similarity coefficient is proposed.Since the synthesis using the method of D-S evidence theory will get unconventional results when there is conflicting information between each evidence,in order to solve the problem of conflict between evidence,this thesis uses the method of indirectly defining the similarity between evidence sources to improve each evidence source,that is,calculating the similarity between evidence by the fuzzy affiliation of each evidence,and using this as the basis to get the credibility of each evidence,using the credibility to correct each evidence body,and finally use the synthesis criterion of traditional evidence theory to make fusion decision.By comparing the D-S evidence theory,the classical improved evidence theory and the improved method proposed in this thesis,the results show that the improved method in this thesis can effectively solve the conflict problem among the evidence and has higher accuracy.(3)A self-propelled artillery health assessment method based on improved evidence theory is proposed.By considering the performance information,operability information and environmental information of a self-propelled artillery system,the health assessment index system of a self-propelled artillery was established,and the health status criteria and the affiliation degree of each status parameter were determined.After the weight of the relevant state parameters is given,the improved evidence theory method is used to evaluate,and the health state of a self-propelled gun is good.The experimental comparison with Deng Yong’s method shows that the method proposed in this thesis has higher support for the good state and the results are more accurate.This thesis systematically analyzes the health assessment technology of complex equipment,and proposes a health assessment method based on D-S evidence theory by combining the characteristics of self-propelled artillery.The research results show that the method proposed in this thesis improves the accuracy of health assessment to a certain extent and is of great significance to improve the maintenance assurance of self-propelled artillery.