Accelerated aging test for MEMS inertial measurement units using temperature cycling

Bias and scale-factor are the major deterministic error parameters of the inertial sensors and these parameters have to be compensated before integrating sensors to a navigation system as the performance degradation of the sensors is undesirable. The fact is that, deterministic error parameters can dramatically change due to aging. Therefore, aging tests play an important role in determining the life cycle of sensors. Accelerated aging tests are commonly used and most time-efficient method to determine the change in the error parameters. There are generally four types of accelerated aging tests: Temperature Cycling, High-Temperature Operating Life, Temperature Humidity Bias and Vibration. As the aim in this paper is to stress the thermo-mechanical mechanisms in the MEMS sensing units, temperature cycling is used for accelerated aging. Temperature cycling tests are applied to various inertial measurement units in order to simulate 3 years life cycle in a controlled storage environment. Moreover, multi position static and dynamic tests are performed using 2 axis rate table and data is collected from the test units after each 6 months period in cycling in order to analyze the effect of each cycle on the error parameters. Throughout this study the test results, especially the change in the error parameters of the commercial MEMS IMUs in the market caused by temperature cycling corresponding to 3 years controlled storage will be given in detail.