Research On Key Technology Of Welding Robot For Finned Tubes Of Waste Heat Boiler

In actual production,the welding seam of the orthogonal pipe similar to the finned tube of the waste heat boiler and the collecting box is relatively rare.This article takes the welding robot of the waste heat boiler fin tube and the collecting box as the research object.Aiming at the welding problem of the fin tube and the collecting box,this thesis takes the shortest welding path as the target to search for the robot from the initial welding point to the target welding point.Good path,the main research contents are as follows:(1)According to the welding task,choose the ABB IRB4600 robot to complete the welding task.Analyze the kinematics characteristics of the ABB IRB4600 robot,use the D-H method to establish the kinematics model of the robot,and solve the forward kinematics and inverse kinematics according to the transformation relationship between the joint coordinate system and the Cartesian space coordinate system.The robot model is established in Matlab,and the correctness of the forward and inverse kinematics solution is verified through experiments,and the result shows the correctness of the D-H method modeling.(2)The commonly used interpolation method for welding path trajectory of ABB IRB4600 robot with pitch constraint(such as waste heat boiler finned tube)is studied.It mainly introduces the trajectory planning method of joint space and Cartesian coordinate space.On this basis,combined with the pitch constraint,a spatial arc interpolation method with pitch constraint is designed.In Matlab,using the robot toolbox,design different tasks for simulation,and observe the state information and impact of each joint.Experiments show that the trajectory of the spatial arc interpolation algorithm with pitch constraint is smoother,with almost no impact,and the acceleration is smoother.(3)When solving the welding problem with pitch constraint,the pitch constraint is introduced to describe the relationship between the welding points of multiple fin tubes,and the HPSOGA algorithm with pitch constraint is designed to search for the shortest welding path of the robotic arm.The GA algorithm and the PSO algorithm are appropriately mixed to improve the particle diversity of the PSO algorithm,optimize the global search ability of the GA algorithm through mutation operation,and use the exchange operator and the exchange sequence to discretize the update process of the particle state.Import the Solidworks model into Matlab,build an algorithm simulation platform,and use the PSO algorithm,GA algorithm,and HPSOGA algorithm to search for paths.Many experiments show that after 15 iterations of HPSOGA algorithm,the solder joint path of IRB4600 is the shortest,about 51.1258 cm,and the solder joint trajectory is relatively smooth,which verifies the effectiveness and correctness of the algorithm.(4)Import the ABB IRB4600 robot into Robot Studio to construct a single-layer welding workstation for the fin tube and the collection box.On this basis,the robot's movement path was planned,and the offline programming trajectory planning of the workstation system and the welding gun posture adjustment were completed.During the single-layer welding process of the finned tube and the collecting header,the robot motion is smooth without sudden change,and all are within the limit.The experiment shows that the kinematics solution and path planning algorithm of the fin tube welding robot for waste heat boiler are correct.