Analysis And Research On Kinematics And Trajectory Planning Of Welding Robot

In the daily work of welding tasks,the objective welding environment of workers is usually relatively bad,and it is difficult to maintain a high mental state all day without rest.The introduction of welding robot can effectively alleviate the above problems and improve the welding high-quality yield.In order to better apply welding robot in practical production,it is of great significance to study the kinematics and trajectory planning of welding robot.This paper takes the welding robot developed by guogongxin Cangzhou Co.,Ltd.as the prototype,analyzes the kinematics of the welding robot body structure and the trajectory planning of the welding curve,so as to make the welding robot run stably and complete the welding task accurately and efficiently.The main contents of this paper are as follows:(1)Complete the kinematics analysis of welding robot.Firstly,the basic theory of robot kinematics is introduced,selects D-H method to establish the coordinate system and mathematical model for the welding robot,calculates and analyzes the forward kinematics and inverse kinematics of the welding robot;The actual system of the welding robot body construction model is simulated by MATLAB software platform toolbox,and the correctness of forward and inverse kinematics is verified;This paper introduces three methods to solve the workspace of the welding robot,and finally analyzes the workspace of the welding robot by Monte Carlo method.(2)Based on the kinematics model of welding robot,various methods of trajectory planning are further studied.It mainly includes cubic polynomial and quintic polynomial interpolation method in joint space,linear interpolation method and circular interpolation method in Cartesian space,spline function and B-spline curve method.This topic carries on the mathematical derivation and the theoretical analysis to each kind of trajectory planning algorithm,and uses the MATLAB software platform to write the algorithm program,through the simulation results to compare and analyze the advantages and disadvantages of each algorithm.Through theoretical research and experimental simulation,it can be seen that polynomial interpolation algorithm has the problem of fluctuation,spline function has the problem of too much calculation,and cubic B-spline interpolation algorithm can effectively reduce the jitter problem in the welding process,and realize the robot moving smoothly and reaching the solder joint accurately,so B-spline curve algorithm is selected for the follow-up trajectory planning of welding robot.(3)The software and hardware platform of welding system is built,and the practical application of welding robot trajectory planning is studied.The welding curve pose points are taught on the welding platform,and the effective joint angles of each joint are calculated through the inverse kinematics algorithm.B-spline is used for trajectory planning simulation,and the welding platform is used for practical verification to prove the rationality and feasibility of the trajectory planning algorithm.Two kinds of swing welding commonly used by welding robot are discussed: plane swing welding and space swing welding,and the actual verification is carried out,ensure the welding quality in practical application.