Vulnerability analysis and reliability improvement

The focus of reliability management in this phase is on identifying weak points at an early stage and achieving continuous reliability improvement. The phase of weak-point analysis and reliability improvement extends from product conception to the product’s readiness for series production. Typical methods for this phase of reliability management are FMEA and FTA. These are qualitative reliability methods that systematically identify potential causes of failure based on expert knowledge. The Failure Mode and Effects Analysis (FMEA) method is one of the most widely used reliability methods in industry. It is used to systematically detect failure mechanisms, evaluate their impact and define countermeasures to prevent failures. It is used both with regard to the design as D-FMEA and with regard to the manufacturing process as P-FMEA and thus covers potential sources of error in design and production.

Similar to FMEA, fault tree analysis (FTA) aims to identify all possible failure types and their causes. Starting from the system failure, failures of the next lower level are collected and linked step by step from the system level to the component level. The result is a fault tree that describes all possible fault causes and their links for the failure of a system.

The Highly Accelerated Life Test (HALT) is an iterative process in which the system is first tested with an excessive load until failure occurs. The failure mechanism is then examined to identify design vulnerabilities, which are then remediated in the next step. The three steps of testing, failure analysis and design improvement are repeated in a loop until all relevant vulnerabilities for customer use are identified and corrected.