Research On Region Prediction And Template Matching Based Weld Tracking Algorithm And System

Pipeline transportation is an important means of transportation of oil and natural gas in China,how to complete the welding work with high efficiency and high quality is the key to ensure the safety of transportation.In this thesis,a seam tracking welding system is designed according to the characteristics of pipeline weld image.The main works are as follows:1)A set of automatic welding system for seam tracking is designedIn this thesis,a set of welding seam tracking system is designed.The main components of the system include a system control module,a image acquisition module,a deviation calculation module,a motion control module,a motion module and a welding module.The image data collected by image acquisition card is transmitted to the computer,and the computer calculates the weld deviation through the proposed algorithm and transmits the deviation to the motion control card.Then the deviation data is converted to the corresponding pulse by the motion control card and the pulse is transferred to the motor controller through the wire.Finally,the motor controller controls the rotation of the motor to complete the deviation adjustment.2)A tracking algorithm based on region prediction is proposedIn this thesis,a template matching algorithm is presented based on the combination of gray feature and gradient direction histogram feature,and it can locate the weld position accurately.A matching region prediction algorithm is proposed to improve the running speed of the algorithm,and it can realize real-time tracking.A template-updating strategy is proposed to improve the robustness of the system.The proposed tracking algorithm can find the location of the weld accurately and achieve real-time tracking,and it is robust to occlusion and appearance changing of the target.3)The implement of weld automatic weld tracking systemUnder the Windows environment,we use C++ language to implement the real-time tracking interface,the algorithm adjustment interface,the locale parameters interface and the installing parameters interface.The system uses digital input and output card to implement tracking start,tracking stop,manual adjustment,system shutdown and other functions.