复杂力学环境中MEMS安全系统失效机理与分析方法研究

发布时间：2018-06-09 04:17

本文选题：MEMS + 安全系统　；参考：《北京理工大学》2014年博士论文

【摘要】：采用微机电系统(MEMS)技术是实现引信微小型化的有效途径之一，MEMS技术应用于引信中的一个重要方向就是MEMS安全系统。失效是阻碍MEMS安全系统实际应用的一个关键问题。由于其应用背景较为特殊，目前国内外对MEMS安全系统失效研究的报道很少，也没有建立相关的失效分析理论，因此开展MEMS安全系统失效研究工作，对于解决MEMS技术在引信中应用的关键技术问题具有重要意义。研究复杂力学环境中MEMS安全系统的失效问题，首先从分析复杂力学环境的环境载荷特点入手，结合MEMS的工艺特点、产品结构特点、典型材料特性，分析系统失效模式和失效机理，进而明确失效判据。为全面有效地分析问题，确定复杂力学环境中MEMS安全系统的失效模式为时序失效和功能失效，其中功能失效是由于环境过载造成器件的强度失效所致，而时序失效是由系统作用时序混乱而引发的失效。而后针对研究对象确定可行的失效分析方法。根据MEMS安全系统的特性并参考对MEMS器件的失效分析方法，本文提出了采用事前分析模式思路、针对复杂力学环境中MEMS安全系统的失效分析方法。既利用失效树分析法结合对已设计安全系统的分析结果，对系统进行失效判断。利用建立系统数学模型的方法分析系统对复杂外力的响应，以此考察复杂力学环境中MEMS安全系统的性能。根据执行功能的不同，将MEMS安全系统划不同的功能单元进行独立分析，通过对系统简化将各单元的作用过程简化为其内部的关键器件的运动或形变过程，这样系统的性能最终可由器件的响应来体现。将关键器件归类并分别建立其相应的动力学、运动学模型，以此分析其对外加环境力的响应。然后以20mm小口径弹的MEMS安全系统为例，利用上述分析方法对其进行复杂力学环境中的失效分析。分别建立20mm小口径弹的MEMS安全系统的安全性和作用可靠性失效树，并通过求解最小割集的方法明确其精确失效判据；根据所建模型计算勤务处理过程和引信作用过程中20mm小口径弹的MEMS安全系统不同功能单元关键器件对外力的响应，将结果对比失效判据对系统是否失效进行判定。最后利用ANSYS和ADAMS工程软件分别建立20mm MEMS安全系统三维模型，并对其进行复杂力学环境中的仿真实验，以此验证所建模型的正确性和该失效分析方法的可行性。
[Abstract]:It is an effective way to realize the miniaturization of fuze by using MEMS technology. MEMS safety system is one of the important directions in the application of MEMS technology in fuze. Failure is a key problem that hinders the practical application of MEMS safety systems. Because of its special application background, there are few reports on the research of MEMS safety system failure at home and abroad, and no relevant failure analysis theory has been established, so the research work of MEMS safety system failure is carried out. It is of great significance to solve the key technical problems in the application of MEMS technology in fuze. In order to study the failure of MEMS safety system in complex mechanical environment, the first step is to analyze the environmental load characteristics of complex mechanical environment and combine the process characteristics of MEMS. The characteristics of product structure, typical material, failure mode and failure mechanism of the system are analyzed, and the failure criterion is determined. In order to analyze the problem comprehensively and effectively, the failure modes of MEMS safety system in complex mechanical environment are determined as sequential failure and functional failure, among which the functional failure is caused by the failure of the device strength caused by the environmental overload. The time series failure is caused by the chaos of the system action time series, and then the feasible failure analysis method is determined for the research object. According to the characteristics of MEMS safety system and referring to the failure analysis method of MEMS devices, this paper proposes a method of failure analysis for MEMS safety system in complex mechanical environment. Both the failure tree analysis method and the analysis result of the designed safety system are used to judge the failure of the system, and the response of the system to the complex external force is analyzed by the method of establishing the system mathematical model. The performance of MEMS safety system in complex mechanical environment is investigated. According to the different executive functions, the MEMS safety system is divided into different functional units for independent analysis. By simplifying the system, the action process of each unit is simplified to the movement or deformation process of the key devices within the MEMS system. In this way, the performance of the system can be reflected by the response of the device. The key devices are classified and their corresponding dynamic and kinematic models are established to analyze their responses to external environmental forces. The above analysis method is used to analyze the failure in complex mechanical environment. The failure tree of the safety and reliability of 20mm small aperture projectile is established, and the exact failure criterion is determined by solving the minimum cut set. According to the established model, the response of key components of different functional units of 20mm small caliber projectile to external force is calculated during the process of service processing and fuze action. Finally, the 3D model of 20mm safety system is established by using ANSYS and Adams engineering software, and the simulation experiments in complex mechanical environment are carried out. The validity of the model and the feasibility of the failure analysis method are verified.
【学位授予单位】：北京理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TH-39

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