嵌入式数控系统的结构可靠性分析

Structure Reliability Analysis of Embedded CNC System

当前对数控系统可靠性研究主要是一种滞后的可靠性研究,是对于成熟产品使用中出现的故障的研究,侧重于系统维修方面,而很少从可靠性工程的角度来研究.为此,对处于可靠性工程早期阶段的嵌入式数控系统的结构可靠性进行了分析和建模,给出基于实时操作系统(RTOS)平台的嵌入式数控系统层次化模块结构图,在对数控系统功能和实际开发过程分析的基础上,对传统的Littlewood模型进行了改进,得到了改进的Littlewood模型,即Improved-Littlewood模型,并将模型用于一个嵌入式数控系统的结构可靠性设计阶段,给出了模型中各种参数矩阵的确定方法,最后得到系统的结构失效密度模型和可靠度模型,验证了方法的可行性.

Current research on the reliability of computerized numerical control（CNC） systems is mainly focusing on the breakdown in matured products and system maintenance,while there has been little interest in the CNC system reliability from the perspective of reliability engineering.Therefore,structure reliability analysis and modeling of embedded CNC system,which are in the early phase of the reliability engineering cycle,have been conducted,and the hierarchical module chart of the system based on real time operation system（RTOS）has been put forward.The improved-Littlewood model has been proposed on the basis of analysis of the functions and real development process of the CNC system and applied to the structure reliability analysis of an embedded CNC system.Methods to determine the variant parameter matrixes have been given,and the model of failure density structure and the reliability model of the system have been obtained,which verifies the feasibility of the proposed model.