ABSTRACT
Lock mechanism is one of the important and problematic components on aircraft, whose performance and reliability directly affect the mission or even safety of the aircraft. However, lock mechanism always have characteristics of complex forms, few samples and high reliability, traditional reliability assessment methods and reliability test method based on statistics is not appropriate for its reliability assessment. In addition, damage of the lock components increase with work time, the damage will make the performance of lock mechanism degradation or even cause failure. Therefore, reliability of the lock mechanism is not only function of random variables but also function of work time. In this paper, a time-variant reliability analysis method based on physics of failure was put forward, in the method, both time-invariant factors and time-variant factors are considered, and the degradation model of the components can be obtained from both practicality experiment or damage mechanism model. Taking a lock as the study object, failure modes and failure mechanism of the lock mechanism were analyzed combined with dynamical responses. Then, Response Surface Method (RSM) was used to obtain relationship between design variables and dynamic responses. Component damage was regard as a random process, after damage degradation law was obtained, considering randomicity of all the parameters, lock mechanism reliability with work time was obtained and the reliable life was predicted.
