Abstract:

The defects of vehicle Anti-Lock Braking System (ABS) seriously affect the vehicle safety, and these cause defective vehicles' recall. But it is difficult to obtain accurate quantitative results according to the fuzzy description in defect hazard assessment with a traditional FMECA (Failure Mode, Effect and Criticality Analysis)
method. After analyzed the defect modes of vehicle ABS, a modified fuzzy FMECA method was proposed by using fuzzy comprehensive evaluation method in FMECA with establishing three fuzzy evaluation indexes of defect severity, occurrence and detectability. The defect harm degrees of six failure modes were ordered taking
an ABS motor as an example of defect risk assessment. The result shows that the modified fuzzy FMECA method can assess the risk of defects more accurate than traditional FMECA method because of considering the Risk Priority Number (RPN) of three defect fuzzy evaluation indexes. Therefore, by using this modified method can assess the vehicle brake system defects risk, and also has a positive meaning to improve the vehicle recall management efficiency.

Key words: vehicle recall, anti-lock braking system (ABS) defects, risk assessment, fuzzy comprehensive evaluation, FMECA (Failure Mode, Effect and Criticality Analysis) method