Study On Thin Plate Welding Seam Tracking System Based On Rotating Arc TIG Welded

With the development of the new form of economic, there has made great development in construction, automotive, aerospace and other industrial sectors. The consumption of steel is increasing. Before being applied in various fields, most of the steel must be processed into finished products by welding.The application of steel sheet accounts for a large part of the steel. In order to improve the production efficiency and improve working conditions for workers, the research of intelligent welding system is particularly important.This paper designed a set of seam tracking system which is based on rotating arc sensor of TIG welding of sheet. We set up a platform for TIG welding with some equipments, including TIG welding power source, wire drive feeder, rotating arc sensor, cross slider, mobile car, etc.Based on C language, we also write the entire data acquisition, processing program and control program.Because of the strong interference in the process of TIG welding, designed a trigger pulse shaping circuit ensuring that the trigger pulse of opto-coupler can accurate sent to data acquisition card. In addition, this paper filters the collected arc voltage with the combination of median filter and mean filter method. In order to get better filter effect, this paper adopts the method which use several times of mean filter method. Then integral and characteristic harmonic method is used to identify the deviation. In order to enhance anti-jamming ability, this article uses a new method to get the final deviation of the data.The deviation is fused by using integral method and characteristic harmonic method.In view of the traditional PID controller is difficult to control the nonlinear, uncertain controlled object. This paper adopts the fuzzy PID controller. We acquire control experience through the incremental. Then we achieve the real-time parameter setting and improve the accuracy of seam tracking by using the fuzzy control to get three parameters of PID.Finally, verified the integrated filter method has obtained filtering effect by V groove welding seam tracking experiment. The fusion of deviation could improve the ability of resistance to outside interference. The results of the experimental show that the design of fuzzy PID controller has better control precision and the seam tracking system researched had achieved the research purposes expected.