基于模糊故障树的数控机床故障诊断方法

Fault Diagnosis Method of CNC Machine Tool Based on Fuzzy Fault Tree

以数控车床螺纹加工为典型实例,按功能分解方法构建数控系统的故障树,用案例推理法对故障树规则进行描述。根据隶属度最大原则建立数控机床故障原因的推断方法。结合机床实际生产和使用维修中统计的故障数据,运用模糊故障树控制理论建立故障集度矩阵,可判定故障机制隶属度。该方法可提高数控机床系统故障诊断的工作效率和准确性,并为故障诊断专家系统的设计提供一种新的推理方法。

A fault tree of CNC systems was developed by functional decomposition,which took a representative instance for thread machining on digital controlled lathe. The fault tree regulation was demonstrated by case-based reasoning. A method to infer failure cause of CNC lathe on the basis of maximum degree of membership was established. By using in combination the failure data collected from maintenance of the factories manufacturing machine tools,the malfunction intensity matrix was set up based on control theory of fuzzy failure tree,which was able to use to decide degree of membership about a failure mechanism. This method can improve the working efficiency and veracity of system fault diagnosis of CNC machine tool,which also can offer a new inference method to design expert system for fault diagnosis.