Research On Association Matrix Between Multi-performance And Multi-faults Of CNC Machine Tool

Manufacturing is the core power of our country’s economic development.As the main equipments of the manufacturing,our country attach great importance to the Computer Numerical Control(CNC)machine tools’ development.The complex structure and diverse functions of CNC machine tools determine the variety of failure modes and performance characteristics,the failure modes and performance characteristics are not independent.When the degradation of the performance reaches a certain threshold,it will lead to the occurrence of failure.At the same time,the occurrence of failure will exacerbate the degradation of performance.Therefore,it is very important to both study the relationship between the performance characteristics and the failure modes of the CNC machine tools and to construct the quantitative correlation between the performance feature and the failure rate,which is of great significance to evaluate the reliability of the CNC machine tool.The main research contents of this paper are as follows:(1)This paper digs out the relationship between the performance characteristics and the failure mode,and constructs an relation matrix model from the internal mechanism of multi-performance and multi-failure.(2)Multi-performance degradation variables are used to fit the degradation path and obtained pseudo-failure lifetime,from which we can calculate the reliability and failure rate function of the CNC machine tool.(3)Based on the expert fuzzy theory,expert system is used to obtain the relation extend evaluations between the performance characteristics and the failure modes.According to the expert’s evaluation transformed into triangular fuzzy numbers,we can get the exact quantitative relation between the degradation variable and the failure rate.By the failure rate ratio and overall failure rate,we can get the failure rate of each CNC machine tools’.(4)This paper obtains the performance characteristic by the raw data of experiments platform of CNC machine feed system and further determines the failure rate of each CNC machine tool’s failure by relation matrix between multi-performance and multi-failure.Finally,comparison with the failure rate obtained by the actual feed system fault record table is made to validate the accuracy and feasibility of the method.