Quality Monitoring of Resistance Spot Welding Based on a Digital Twin

As an important means to realize intelligent manufacturing, a digital twin is a digital expression of physical entities, which realizes virtual–real interaction and the iterative optimization of product design and manufacturing by constructing a bridge of information mapping between the physical world and the virtual world. Resistance spot welding technology is widely used in automotive manufacturing, aerospace and other fields as a spot linking process for the manufacture of thin sheet structures. The fusion nugget growth process of resistance spot welding is particularly important for its joint quality. Resistance spot welding is a highly nonlinear coupled process, and physical models make it difficult to accurately monitor its quality. Taking 2219/5A06 aluminum plates with different thicknesses as the research object, digital twin technology is applied to monitor the welding process of aluminum plate. In order to improve the key technologies such as information interaction in the digital twin system, a data acquisition system for resistance spot welding process is established and a real-time data processing technology based on wavelet threshold analysis is proposed. Based on real-time data, the processed process parameters are tested in twin space to validate the feasibility of the solution.