基于层次分析法的数控机床精度模糊评价

Fuzzy comprehensive evaluation of the accuracy of CNC machine tools Based on AHP

为了全面准确地评价数控机床的精度,建立了考虑了几何误差、位置误差、热误差及加工误差因素,分为三个层次的数控机床精度评价指标体系。该体系采用层次分析法(AHP)确定数控机床各项性能指标的权重系数,运用模糊综合评判法对各项精度指标进行评价,以中间形梯形分布函数为依据构造隶属度函数,利用软件实现算法的仿真,并生成精度评价报告。以某型五轴数控机床为研究对象,运用三级模糊综合评价法对其精度进行了评价,得出了有利于改进机床精度的结果,验证了上述精度评价方法的可行性。该方法可用于评价其他机床的精度。

In order to evaluate the accuracy of a computerized numerical control （CNC） machine tool comprehensively, a 3-level accuracy evaluation index system for CNC machine tools was established under the consideration of the error factors of geometry,position, heat, and machining. The system determines the accuracy index weight coefficient by using the analytic hierarchy process （AHP）, evaluates each accuracy index of a machine tool by using the fuzzy comprehensive evaluation, and constructs the membership function according to the intermediate form trapezoidal distribution function. A five-axis numerical control machine tool was evaluated by using the above-mentioned meth- od, and the results indicate that the accuracy evaluation method is feasible and effective in application. The presen- ted method can be used to evaluate the accuracy of other numerical control machine tools.