Research And System Development Of On-site Measurement For Ring Seam Welding Process Of Large Thin-walled Tank

On-site measurement technology in the manufacturing process of aerospace products is a research hotspot in the field of digital manufacturing.In the ring seam welding process of large thin-walled tank in a rocket structure,the dimensional control of the tank components and the accurate measurement and positioning of the relative spatial orientation of the tank components to be welded play a key role in the welding quality.Therefore,research and system development of on-site measurement technology for ring seam welding process of large thin-walled tank is of great significance to improve the quality of rocket manufacturing.This paper relies on the topic of "Study on the on-site measurement technology for ring seam welding of large thin-walled tank".In order to solve the problems in the current measurement method such as some key position tolerance cannot be measured,measurement accuracy and consistency is poor and management of the measurement process is lacking,the on-site measurement technology for the ring welding process of large thin-walled tank was studied.Firstly,according to the ring seam welding process of the tank,the key geometric parameters affecting the quality of the tank are summarized.Based on this,the on-site measurement process and measurement integration scheme are determined.Secondly,this paper proposes a multi-station data fusion accuracy model based on coordinate uncertainty transfer,which lay a theoretical foundation for the highprecision laser tracker measurement method.Then,based on genetic algorithm,a measurement layout optimization method for the improvement of the visibility condition and measurement accuracy is proposed.The effectiveness of the layout optimization method is preliminarily verified by simulation and experiments.Furthermore,the onsite measurement software and hardware system are developed.Finally,the reliability of both the measurement method and the system developed is validated by field measurements results.