A fuzzy maintainability allocation method for NC machine tools based on interval analysis

In the process of maintainability allocation of numerical control (NC) machine tools, many influence factors should be considered, and some of which are difficult to analyze quantitatively. In order to solve the above-mentioned problem, this paper proposed a new method for maintainability allocation, which comprehensively applied interval analysis, fuzzy comprehensive evaluation, and analytic hierarchy process (AHP). The allocation model is built which can make use of the test information and expert´s experience comprehensively. Meanwhile, as the information carried by a single real number is always incomplete, interval number is used instead of real number to construct judgment matrix. Finally, the method is illustrated with an example, and the maintainability indexes of all subsystems are obtained as well. The analysis results show that the method is a feasible method for the maintainability allocation of NC machine tools. It could solve the uncertainty problem of maintainability allocation for NC machine tools effectively.