Research On On-line Monitoring Of Arc Welding Additive Manufacturing System Based On Multisensing

With the development of metal additive manufacturing technology,As a new metal forming process,arc welding additive manufacturing technology has attracted more and more research institutions’ attention.The monitoring of arc welding additive manufacturing is one important means to improve the quality of arc additive manufacturing and improve the yield rate.Therefore,in this dissertation,a monitoring system for arc welding additive manufacturing based on infrared vision and signals of current and voltage was built.Infrared images and signals of current and voltage were collected through experiments.The infrared images and signals of current and voltage of the three arc welding additive manufacturing defects are collected through the design experiments The infrared image features and characteristics of current and voltage signal are studied separately.And corresponding defect identification algorithms were designed according to the characteristics.This provides a multi-sensor compound online monitoring approach for arc welding additive manufacturing.The main contents of this paper include the following points:An Infrared Thermography with a wavelength of 7.5~13μm,a closed-loop Hall current sensor and a Hall voltage sensor are selected.According to the characteristics of GMAW arc welding additive manufacturing,the entire monitoring system was rationally designed and built,and the infrared image and signals of current and voltage in the arc welding additive manufacturing process were effectively acquired.Three sets of comparative tests were designed and performed according to the design.Three typical arc additive manufacturing defects,such as discontinuity,collapse,and porosity,were successfully manufactured during the experiment.Infrared image and signals of current and voltage were collected during the process.The infrared image and signals of current and voltage collected during the defect generation processes were analyzed in detail.The corresponding characteristics of each defect are summarized,which lays a theoretical foundation for the design of defect recognition algorithm.According to the corresponding characteristics of the defects,the corresponding defect recognition algorithms were designed by using the functions of OpenCV.And the three defects can be accurately identified.The software of infrared and multi-sensors on-line monitoring system was developed using the WPF framework.The software has a friendly interface.It can realize the real-time acquisition of infrared images and signals of current and voltage in the arc welding additive manufacture process.It can identify three typical defects in the arc welding additive manufacture process and record the whole process.