Study On The Seam Tracking System Based On Alternative Current Field Measurement

With heavy labor intensity and bad condition, the welding is a hard job which needs the worker having high technology. So, the welding process automation is the key to improve the welding products quality and the production efficiency, and the auto weld tracking is an important link of the automatic welding. Therefore, developing a seam tracking system, which have good performance and is economical and practical is an urgent problem to be solved. The main research in the text is Study on the Seam Tracking System Based on Alternative Current Field Measurement(ACFM).Firstly, a brief introduction of domestic and international trends of the welding automation and the auto seam tracking technology is made. Secondly, it is depicted that the development and application of Alternative Current Field Measurement technology. Finally, the feasibility of ACFM technology in seam tracking is analyzed according to the principle and characteristic of the ACFM technology.After the theory foundation and basic principle of the ACFM technology is set forth, the whole structure of the seam tracking system is designed, which include the main structure, drive coil,induction coil,drive signal power, former electrocircuit and the anti-jamming measures of system. It offers a stable and reliable signal for the seam tracking system and settles a well foundation for signal disposal.As the induction signal is faint, the correlated detect technology is adopted, which is a mature technology that can magnify the signal and restrain the noise. It can detect the value and phase of the signal and export it as the form of direct current, so can reduce the requirement for the sampling frequency of the A/D sampler. So, the hardware electrocircuit is designed and the signal is exampled.According to the characteristic of the induction signal, the sampling-keep system is designed and the max sampling method is used to get the induction signal. The PID arithmetic is to minimize the departure and to make the welding torch always to be in the middle of the seam in order to finish the seam tracking.Finally, on the basis of above introduced design finished the adjusting of the whole system, realized the auto seam tracking, and proceeded with the analyzing and appraising of the results of the auto seam tracking experiments.