Study On The Acceleration Factor Of Vehicle Accelerated Life Test

The research of acceleration factor of vehicle accelerated life test is very important in many realms, such as organizing intensifying test, formulating its criterion, designing vehicle proving ground, etc. It can result in timesaving, cost cutting and quality improving in vehicle product. Furthermore, it also supplies theoretic basis for revealing failure rules of vehicle, formulating and modifying maintainable updating plan of vehicle. After investigating the research trends both from foreign countries and domestic, analyzing the existed various number of research methods of acceleration factor, this dissertation try to find out a new way to research the acceleration factor. First of all, vehicles always ground in before taken accelerated life test. This fact is not considered in Weibull Process model. In this paper, the location parameter is first introduced into Non-Homogeneous Poisson Process model. Then, the modified Weibull Process model including the location parameter is put forward, The experiment data proves that the simulation precision is highly improved. Considering the influence of the location parameter, the calculated method of acceleration factor is modified to fit for actual condition. Secondly, because that modified Weibull Process model cannot describe the failure statistics rule of different phase in maintainable system in detail, a method of establishing new Non-Homogeneous Poisson Process model is posed. Based on this method, Logarithm Process model and Exponential Process model is established. The Logarithm Process model adapts to describe early failure phase and random failure phase, the Exponential Process model fits for different phase. The maximal error vaue of parameter estimation in each new mode is tess than 7%, which is eval.uated by a computer simulation program. The simulation precision is improved in compared with that of modified Weibull Process model, which is confirmed by experiment data. Thirdly, the acceleration factor put forward in this paper is varied according to running miles (or running time). In this report, the concept of the function of acceleration factor, the equivalence acceleration factor, all life equivalence acceleration factor and overhauling life equivalence acceleration factor are introduced. Corresponding to actual running mile, the correctional algorithm of equivalence running time in accelerated life test has been developed. Finally, based on the theory of stochastic processes, a research accelerationfactor method of different with existed method is proposed.