A novel fault diagnosis approach of a mechanical system based on meta-action unit

Xiaogang Zhang,Genbao Zhang,Yulong Li,Hongwei Wang,Xiansheng Gong,Yan Ran

doi:10.1177/1687814019826644

Abstract

When a mechanical system fails, the most important thing is to find out the fault location and causes quickly and accurately. Based on the meta-action unit, this article proposes a comprehensive, qualitative, and quantitative fault diagnosis method composed of fault tree analysis and evidential network to analyze faults of the mechanical system. First, we expand the function–motion–action decomposition method, revise the definitions of meta-action and meta-action unit derived from the function–motion–action decomposition of the complex mechanical system, use the fault tree analysis approach to analyze the faults of the meta-action unit instead of the system directly, and establish the meta-action unit fault tree analysis (MU-FTA) model with simple levels. These activities can tremendously simplify the qualitative diagnostic model. Second, the MU-FTA model is mapped to the evidential network model according to their similarities. Finally, we fuse the after-sales data and expert experience information by Dempster’s combination rule to calculate the basic probability assignments of the parent nodes in the bottom layer of the evidential network model. Thus, the basic probability assignments of meta-action units are obtained by network transmission and the diagnostic conclusion is acquired. The fault diagnosis of a certain type of numerical control turntable is conducted as an example to demonstrate and verify the feasibility and effectiveness of the proposed approach.

Highlights

A fault appears when the product cannot perform the required function.[1]
Based on the transformation relationships given by Simon and Yang, we construct the meta-action unit evidential network (MU-EN) model to analyze the fault of a complex mechanical system quantificationally
We extend the product category, the application scope of the FMA decomposition method is only the mechanical systems of these products/systems

Summary

Introduction

A fault appears when the product cannot perform the required function.[1]. The activities of fault diagnosis usually involve fault location, fault mode analysis, and fault reason analysis. Keywords Function–motion–action decomposition method, meta-action unit, fault diagnosis, fault tree analysis approach, evidential network In order to help maintenance personnel find the fault location and fault causes, a novel hybrid fault diagnosis method including the fault tree analysis (FTA) and evidential network (EN) is proposed for the complex mechanical system of product in this article.

Results

Conclusion