Variational modal decomposition (VMD) has the end effect, which makes it difficult to efficiently obtain fault eigenvalues from rolling bearing fault signals. Inspired by the mirror extension, an improved VMD is proposed. This method combines VMD and mirror extension. The mirror extension is a basic algorithm to inhibit the end effect. A comparison is made with empirical mode decomposition (EMD) for fault diagnosis. Experiments show that the improved VMD outperforms EMD in extracting the fault eigenvalues. The performance of the new algorithm is proven to be effective in real-life mechanical fault diagnosis. Furthermore, in this article, combining with singular value decomposition (SVD), fault eigenvalues are extracted. In this way, fault classification is realized by K-nearest neighbor (KNN). Compared with EMD, the proposed approach has advantages in the recognition rate, which can accurately identify fault types.
In view of the lack of unified data architecture and model of workshop transportation system components, this paper proposes the concept of the workshop transportation system functional unit based on asset administration shell (AAS). The designed workshop transportation system can solve the problem of unified modelling for different types of equipment, and realize the rapid construction and adjustment of the system. Meanwhile, the system has been applied in the specific workshop transportation system and enables well application results. In the functional unit of workshop transportation system, automatic markup language (AML) is applied. This paper constructs the AAS model based on the industrial 4.0 reference architecture model (RAMI4.0), and introduces the workshop transportation system AAS model and its realistic mapping as an example. The workshop transportation system functional unit AAS model based on the RAMI4.0 provides an effective solution for the standardization and integration of workshop transportation system components, which is no requirement to develop specific data conversion tools for this purpose. All transportation equipment with AAS can achieve information exchange and interoperability. It is conducive for the rapid implementation of workshop transportation system engineering and provides a guide for the establishment of intelligent workshop. Thereby, the proposed methodology demonstrates the flexibility and interoperability of AAS in smart manufacturing.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.