The motion output accuracy of the mechanism has been significantly affected by the performance degradation of components. In this paper, the cumulative factor of wear degradation is considered. On the premise of small samples, an analysis method of time?varying reliability of mechanisms is proposed. This analysis method applies the cosimulation of ADAMS and MATLAB. Based on the Archard wear model, the pin radius degradation is calculated and considered as a time series problem. The mechanism function is established according to the RSM method, and the ARIMA method is used to predict the change of the mechanism response value under the subsequent wear cycle to expand the data samples. Based on the interference model of stress?strength,the limit state equation of mechanism is established and the time?varying reliability is calculated. The convenience and accuracy of this method are demonstrated with a crank?slider mechanism.

In order to improve the accuracy of gasifier risk assessment, a safety assessment method that combines cloud model with catastrophe progression method was proposed. Through literature review and expert analysis, the risks of the gasifier are divided into mechanical systems, personnel, management and environmental risks, and a multi?level risk assessment system for the gasifier was established. The cloud model is an effective tool for qualitative and quantitative conversion. The entropy and hyper?entropy feature values of the cloud model were introduced, and the cloud entropy weight method was proposed to improve the traditional weight calculation method, and the weight calculation of all indicators was carried out to improve the accuracy of the ranking results. According to the normalization formula, the mutation membership value of each layer index and the total mutation membership value of the gasifier are calculated, and the risk level of the gasifier is judged according to the risk level evaluation table. The research results show that this method improves the comprehensiveness and objectivity of the weight ranking, and makes the gasifier risk assessment results consistent with the actual situation, which verifies the feasibility and effectiveness of the method.