【作者】 仲德双；

【导师】 刘彬；

【作者基本信息】 燕山大学 ， 检测技术与自动化装置， 2009， 硕士

【摘要】 故障诊断需要大量专家的专业知识和工程技术人员的专业经验,所以,可采用构建专家系统来进行。故障分离有多种方法,其中故障树分析(FTA)法是较为简捷有效的方法。本论文通过分析专家系统、故障诊断、故障树分析的理论原理,确定了取料机故障诊断专家系统的设计思路,并给出了软件设计方案。故障树分析法是一种图形演绎法,是通过对可能造成系统故障的各种因素(包括硬件、软件环境、人为因素等)进行分析,画出逻辑框图(即故障树),再对系统中发生的故障事件,作由总体至部分按树枝状逐渐细化的分析,其目的是判明基本故障,确定故障原因,故障影响和发生概率等。讨论了故障树分析方法在故障诊断中应用,给出了故障树的建立方法及故障树模型在故障诊断专家系统中的推理策略,最后,结合取料机自身的故障模式特点,完成了取料机故障树的建立。采用基于规则的知识表示方法,深入对基于规则的知识表示方法进行了研究,给出了基于规则知识表示知识库设计思路和数据库的设计方法,并举例说明了实际的专家知识在数据库中的组织情况。在推理机的设计方面,给出了基于黑板模型的推理机设计方法,详细阐述了基于黑板模型的专家系统的结构和求解过程,给出了推理过程中不确定性特征模糊处理算法。最后,将正向推理应用到基于黑板模型的推理机中,得出了取料机故障诊断专家系统推理机的设计流程图。通过对完成课题所需的相关理论的分析,论文结合用户需求初步确立了建立专家系统的软件框架,实现了数据采集模块,知识库管理模块,推理诊断模块,专家系统解释模块等。实践表明此故障诊断专家系统对提高取料机的维修效率有很大的促进作用。更多还原

【Abstract】 Fault diagnosis needs large quantity of experts’professional knowledge and engineers’experience. So, people usually use Expert System to achieve. There are many methods for fault analysis; Fault Tree Analysis (FTA) is among those who are simple and efficient. The dissertation analyzes the concept and theory of expert system, fault analysis and fault tree analysis method, therefore asserts the designing procedure and the software designing blue print.Fault tree analysis is a method of graphics. Analyze all kinds of factor probably causing the system fault, including hardware, software and human. Then we can draw the logical graph (fault tree), and gradually analyzes the fault factor from top to bottom in branches. The objective is to ascertain the basic fault, the causation, the influence and accruing probability.The fault tree analysis in fault diagnosis applications was discussed. Given the establishment of the fault tree and fault tree model in fault diagnosis expert system inference strategy. Finally, based on the failure mode characteristics, completed the fault tree of the reclaimer.Using rule-based knowledge representation, rule-based knowledge representation that has been studied in-depth. Given the method of the rule-based knowledge database design, illustrated the expert knowledge organization in the database of the expert system.Given the design method of inference engine based on the blackboard model. Described the structure and solve process of expert system based on the blackboard model.Finally, the forward reasoning was applied to the inference engine machine based on blackboard model, achieved the inference engine design flow chart of fault diagnosis expert system for reclaimer. Based on the analyzing of the corresponding theory to be needed and the user’s requirement, the dissertation asserts the software frame of the expert system. There are data collection module, knowledge database management module, inference and diagnosis module, explanation facility module. The result showed that the fault diagnosis expert system can provide effective help for the reclaimer maintenance.更多还原