Reliability Modeling And Analysis Of Armored Vehicle Power-shift Steering Transmission

Power-shift steering transmission is one of the core components of a certain type of armored vehicle, whose reliability is an important factor influencing the availability of the whole system, so its reliability analysis is of great significance. However, the power-shift steering transmission is expensive, and there are not enough samples to perform life test, as a result, it difficult to get sufficient failure data in engineering, and its reliability evaluation belongs to the small sample problem. These drawbacks make it a challenge to assess the reliability of power-shift steering transmission. The reliability modeling and analyzing methods based on performance degradation data provide a new approach to the reliability assessment of products with small sample and small amount of failure data. For this reason, the dissertation studies the reliability assessment of power-shift steering transmission based on performance degradation theory, using the oil spectral data to establish performance degradation model. The main contributions are as follows:(1) Failure mechanism of power-shift steering transmission and oil spectral analysis. According to the structure and function characteristics of power-shift steering transmission, the failure mechanism is analyzed with the collected failure information. The dissertation illustrates the basic principle of oil spectral analysis, and makes a detailed analysis on the oil spectral data collecting during reliability test of power-shift steering transmission.(2) Reliability modeling of power-shift steering transmission based on the oil spectral data. The dissertation provide a brief introduction to the basic knowledge of performance reliability modeling, put forward that the content of wearing metals in the oil spectral can be treated as the performance degradation parameter of power-shift steering transmission. This dissertation also studies the pretreatment method of oil spectral data, and process the content data of Cu. The content of Cu is selected as the performance degradation parameter and two reliability modeling methods based on degradation data are studied, including the performance degradation distribution method and the performance degradation path fitting method.(3) Reliability analysis and assessment of power-shift steering transmission. Reliability of power-shift steering transmission is evaluated under different failure thresholds. At last, a detailed comparative analysis is made for the two reliability modeling methods.In this dissertation, the reliability modeling and assessment methods for power-shift steering transmission are proposed, which can also be applied to reliability assessment for other equipments with oil systems. All the data in this dissertation are modified reasonably from project report for confidentiality considerations.