Abstract:

Defects of non-standard problem are judged by using risk assessment method for recalling of defective vehicle products in China. A method of combining fuzzy theory with fault tree was adopted to develop risk possibility analysis to ensure the rationality of risk possibility judgment. The probability of basic events was
obtained by using trapezoidal fuzzy theory. A fault tree model for automobile electric horn was established to calculate the probability of electric horn failure in top events and in basic events. Analyzed the importance degrees, located the faults, and traced the causes in basic events. Compared the failure probability of electric horn with the Weibull distribution of fuzzy fault tree. The results show that the failure probability predicted by using the fuzzy fault tree is in good agreement with that by using Weibull failure probability distribution.Therefore, the fuzzy fault tree can be used to analyze the risk possibility. This method provides a new idea for the risk possibility quantitative calculation.

Key words: defective vehicle products, fuzzy set theory, quantitative analysis, importance analysis