MEMS陀螺仪加速参数退化的可靠度评估

Reliability Assessment of MEMS Gyro Acceleration Parameter Degradation

针对失效时间数据统计方法忽视了退化过程的微观变化和基于性能退化的可靠度评估方法试验需要长时间、多样本才能保证评估精度的问题,提出了MEMS陀螺仪加速参数退化的可靠度评估方法。该方法分析了MEMS陀螺仪的结构特点和能够表征退化的特征参数、敏感应力及加载方式;形成了基于退化轨迹拟合和退化量分布拟合两种方式的加速参数退化可靠度评估方法,并应用于MEMS陀螺仪。通过对比不同评估方法得到的可靠度曲线结果表明,基于退化轨迹的拟合方法过程简洁易懂,基于退化量分布拟合方法建立了分布参数随时间及温度应力的函数,体现了样本参数退化的差异性,更符合陀螺仪退化的实际规律,有助于提高评估的准确度。

The statistical method based on the failure time data ignored the microscopic changes of the degradation process.The reliability assessment method based on performance degradation required long time and multiple samples to ensure the accuracy of the evaluation.A accelerate degradation testing and assessment method was applied to the reliability of MEMS gyro.Firstly,the structural characteristics of MEMS gyro,the characteristic parameters,the sensitive stress and the loading method were analyzed.Accelerated parameter degradation reliability assessment methods based on degradation trajectory fitting and degradation quantity distribution fitting were formed and applied to MEMS gyro.By comparing the reliability curves obtained by different assessment methods,the fitting method based on the degenerative trajectory was simple and easy to understand,the degradation quantity distribution fitting need to establish the function of the distribution parameters with time and temperature stress,which reflected the difference of the degradation of the sample parameters,and was more in line with the actual laws of the degradation of the gyro,which helped to improve the accuracy of the assessment.