How Stress Variance in the Automotive Environment will Affect a ‘True’ Value of the Reliability Demonstrated by Accelerated Testing
نویسنده
چکیده
This paper discusses the effect of the field stress variance on the value of demonstrated reliability in the automotive testing. In many cases the acceleration factor for a reliability demonstration test is calculated based on a high percentile automotive stress level, typically corresponding to severe user or environmental conditions. In those cases the actual field (‘true’) reliability for the population will be higher than that demonstrated by a validation test. This paper presents an analytical approach to estimating ‘true’ field reliability based on the acceleration model and stress variable distribution over the vehicle population. The method is illustrated by an example of automotive electronics reliability demonstration testing.
منابع مشابه
Design and Analysis of Step Stress Accelerated Life Tests for Censored Data}
Life testing often is consuming a very long time for testing. Therefore, the engineers and statisticians are looking for some approaches to reduce the running time. There is a recommended method for reducing the time of failure, such that the stress level of the test units will increase, and then they will fail earlier than normal operating conditions. These approaches are called accelerated li...
متن کاملDesign of Accelerated Life Testing Plans for Products Exposed to Random Usage
< p>Accelerated Life Testing (ALT) is very important in evaluating the reliability of highly reliable products. According to ALT procedure, products undergo higher stress levels than normal conditions to reduce the failure times. ALTs have been studied for various conditions and stresses. In addition to common stress such as temperature and humidity, random usage can also be considered as anoth...
متن کاملCONSTANT STRESS ACCELERATED LIFE TESTING DESIGNWITH TYPE-II CENSORING SCHEME FOR PARETO DISTRIBUTION USING GEOMETRIC PROCESS
In many of the studies concerning Accelerated life testing (ALT), the log linear function between life and stress which is just a simple re-parameterization of the original parameter of the life distribution is used to obtain the estimates of original parameters but from the statistical point of view, it is preferable to work with the original parameters instead of developing inferences for the...
متن کاملOPTIMUM GENERALIZED COMPOUND LINEAR PLAN FOR MULTIPLE-STEP STEP-STRESS ACCELERATED LIFE TESTS
In this paper, we consider an i.e., multiple step-stress accelerated life testing (ALT) experiment with unequal duration of time . It is assumed that the time to failure of a product follows Rayleigh distribution with a log-linear relationship between stress and lifetime and also we assume a generalized Khamis-Higgins model for the effect of changing stress levels. Taking into account that the...
متن کاملQuantitative Accelerated Life Testing of MEMS Accelerometers
Quantitative Accelerated Life Testing (QALT) is a solution for assessing thereliability of Micro Electro Mechanical Systems (MEMS). A procedure for QALT is shownin this paper and an attempt to assess the reliability level for a batch of MEMSaccelerometers is reported. The testing plan is application-driven and contains combinedtests: thermal (high temperature) and mechanical stress. Two variant...
متن کامل