On Bayes Method for Determination of Fault Sample Size Based on Post-test Risk

In view of the problem that the old approach of determining the sample size is too rough and the test sample size is too large, a reasonable application of information entropy method is proposed to obtain the test data of the equipment system by fusing the prior information of each unit of the equipment system. The testability indexes of the prior distribution are obtained, the fault sample size and the test scheme are further determined by Bayes posterior risk criterion. The test data of an electric actuator system's module is taken as an example and the failure detection rate is adopted as the test index, the fault sample size is reduced by 86.5%, and the test index error is figured out as 0.75% compared with the classical test through analysis and calculation, reduce the test cost and guarantee the credibility.