Assembly Process Knowledge Graph for Digital Twin

With the increasing complexity of mechanical products, assembly, as the last step of product manufacturing, is becoming more and more complicated. Therefore, the problems in the actual assembly process are difficult to be considered at the beginning of the design. In addition, the information measured at assembly site is also very important for the improvement of the assembly process design. The emergence of digital twin solves this problem well and provides the possibility for the transmission and feedback of assembly site information. However, the current digital twin data storage side mainly uses the traditional database, which leads to data redundancy. In recent years, the popular knowledge graph has powerful knowledge representation and reasoning ability, which can solve the above problems. In this paper, a digital twin system structure of assembly process based on knowledge graph is proposed, which is used to record actual process data. It provides a possibility for the combination of knowledge graph technology and digital twin technology.