Research On Key Technology Of 6-DOF Robot Laser Remote Welding System

Laser welding has many advantages,such as non-contact,fast welding speed,small thermal deformation,smooth welding surface and so on.In recent years,a new galvanometer scanning welding,also known as laser remote welding,has been developed from laser welding,which further increases the advantages of laser welding.Galvanometer scanning can make the laser quickly locate the welding point,and switch different welds at the same position for many times,so that the positioning time is almost zero,which further improves the processing efficiency and accuracy.The six degree of freedom robot laser remote welding system studied in this paper can weld the car body in white or lithium battery packaging module with high speed,high efficiency and high precision.It will solve the motion coordinates of the six degree of freedom robot and the two-dimensional galvanometer,and also program the order of welding points on the workpiece to reduce the moving distance of the robot end.At the same time,the forward-looking algorithm of the motion speed of the robot and the two-dimensional galvanometer is studied,which makes the whole system move smoothly and efficiently.The research and development of the whole control system must first complete the derivation of the forward and inverse kinematics relationship between the 6-DOF robot and the two-dimensional galvanometer and the joint coordinate solutionLaser remote welding can only scan a certain plane range each time.For the points beyond the current scanning plane,the end of the robot needs to drive the vibrator to move to the next position.Therefore.it will involve the different positioning of the welding position points on the workpiece plane by the end of the robot.Therefore,how to complete all the positioning points with the shortest path will be a path planning problem,This paper uses the improved ant colony algorithm,when the ant colony converges to a local optimal path,if it is still in the current path for a period of time,change the initial parameters of the ant colony algorithm,increase the path randomness,and find a new shortest path randomly.After finding the optimal path,the control system needs to look forward to the speed of multiple segments of the scanning trajectory,each time in a position point will scan multiple segments of different trajectories,these trajectories will have continuous parts,so it is necessary to study the forward looking algorithm of the speed of the joint of the robot and the two-dimensional galvanometer,so as to make the whole welding process smooth and smooth,and achieve the effect of continuous movement.A fast forward looking algorithm is proposed to calculate the maximum allowable speed at each junction from back to front.Then the implementation process of the welding path trajectory is introduced in detail.The periodic position command issued by the control system can make the robot end and two-dimensional scanning point complete a series of motion trajectories such as straight line and arc.The software control system of 6-DOF robot laser remote welding system is developed to realize the orderly and efficient completion of welding,and verify a series of algorithms proposed in this paper.