Resumen
The article is devoted to indistinct expert system for diagnostics of axle-box assemblies. The application of fuzzy systems methodology to the construction of fuzzy expert system for diagnostics of faults of axle boxes has allowed increasing adequacy of the diagnostics model of axle-boxes owing to the use of experience and intuitive knowledge of experts. The fuzzy expert system is able to simulate a course of reasoning of the expert and to explain its actions; also it removes a psychological barrier of misunderstanding in a process of interaction between the user and the system.