Research On The Application Of Digital Twinning Technology In Automatic Painting Workshop Of Ship Section

In view of the problems that it is difficult to monitor the spraying situation in real time due to the diffuse paint mist during the spraying operation in the automatic spraying workshop of large hull sections,and the coating control parameters cannot be adjusted in time due to the lack of real-time measurement and feedback of film thickness,resulting in poor film forming quality and other problems.An intelligent monitoring method based on digital twinning technology is proposed,the system architecture of digital twinning fivedimensional model and the twinning model of key elements of the workshop are established,the virtual-real data interaction and model data-driven technology are studied,and the digital twinning modeling method is adopted to focus on the film thickness and high fidelity digital characterization problem,through the experiment-simulation comparison,The feasibility of the film thickness modeling of the digital twinning system was verified and the high reduction of the film thickness was realized.Through the system integration test,the feasibility of the digital twin system is proved.At the same time,the mobile APP digital twin system and the Web digital twin system were developed,which realized the real-time monitoring of infinite distance,and provided a reference for the intelligent production mode of spraying workshop.The research work of this thesis is as follows:(1)Analyze the overall operational hierarchical architecture of the digital twin system of the hull segmental spraying workshop,make the top-level planning of the design of the digital twin system of the hull segmental spraying workshop,and design the overall architecture and development process of the system by analyzing the system design requirements,objectives and system indicators,and selecting development tools based on the requirements of the five-dimensional digital twin model.(2)The digital twin modeling method of the key elements in the painting shop is studied,including the construction of the geometric model of the digital twin,the physical model of the digital twin,the behavior model of the digital twin and the rule model of the digital twin.It focuses on the construction of physical model and rule model.Through the construction of physical model,the physical entity of the key elements of the workshop is transformed into a digital model,which makes up for the deficiency of the digital twin system lacking sensors.Through the construction of rule model,the implicit relationship between data and the representation phenomenon is established.The real-time prediction and characterization of the film thickness during the data-driven spray gun spraying and the data-driven workshop fault type judgment and alarm are completed.(3)Study the implementation methods of relevant technologies of digital twin system in the painting shop.By analyzing the virtual and real data interaction examples in the shop,adopt the real-time data acquisition and transmission technology based on OPC UA,design the real-time data interaction scheme between the physical space and Unity based on OPC UA,and realize the customization of data acquisition interaction strategy of scene diversity.In order to optimize the system performance,several data-driven models in Unity 3D are compared.By establishing the white box rule model of spray particle deposition film thickness,the characterization method of spray particle deposition film thickness in twin space was studied.In order to solve the problem of workshop security,the UWB based positioning technology is applied to the moving objects in the workshop.(4)Complete the integration test of the digital twin system,including the real-time monitoring function test of the system,the control function test,the UWB based mobile object positioning function test,the system performance test,etc.After passing the test,the mobile APP and the Web end digital twin system were released.Finally,the spraying experiment was completed in the spraying workshop of Waigaoqiao Shipbuilding Co.,LTD.The reliability of the monitoring system was verified by comparing the spraying film thickness of the digital twin system with the experiment.