Research On Welding Trajectory Planning And Control Based On UR3 Robot

Welding is a commonly used processing method in industrial manufacturing.Traditional welding is generally performed by workers,the degree of automation is low,the labor intensity of workers is large,and the quality of welding is often affected by human factors such as worker proficiency.The rapid development of industrial robot technology makes robot welding more and more widely used.In the robot welding operation,the welding ball sequence planning,welding control and welding parameters are the key issues affecting the welding quality.In this paper,the UR3 robot based on the welding problem,on the UR3 robot kinematics,simulation,welding parameters,control and other aspects of these studies.The main research contents and results are as follows:(1)The kinematic model of the UR3 robot is studied.Based on the DH method,the forward kinematics and inverse kinematics models of the UR3 robot are established.Based on the inverse kinematics model,the strange shape of the UR3 robot is further analyzed,and the Jacobian matrix of the UR3 robot is established.Finally,based on the welding plan.In accordance with the requirements of the process,the conversion of the workpiece weld coordinate system and the robot work coordinate system was analyzed,and the corresponding conversion matrix was established.(2)The 3D model of UR3 robot was established using SolidWorks.The UR3 robot kinematics model was established in MATLAB robot toolbox.Kinematics simulation was performed to verify the correctness of the DH parameter kinematics model.The UR3 robot was established in ADAMS.The virtual prototype model simulates and plans the planar “8”-shaped pendulum welding and saddle-shaped welding in welding.(3)The UR3 robot model was established in the ROS(Robot Operating System)robot software framework.Using the sensors and actuators in the ROS,the UR3 robot was planned for motion,and the obstacle avoidance problems that may be encountered in the welding process were performed.In the analysis,the collision detection of the UR3 robot was first studied using the OBB bounding box method,and then the RRT fast search random tree algorithm was used to simulate obstacle avoidance for the UR3 robot.The ROS system was used to obstacle avoidance experiments.(4)Based on MATLAB + ADAMS co-simulation technology,using PID and Fuzzy PID control algorithm,the joint torque of the UR3 robot is used as the input variable,the output variable is the joint angle of the UR3 robot,and the feedback control is used in the middle to achieve the desired control effect.The joint position of the UR3 robot was controlled and simulated.Finally,the experimental equipment and materials were selected to verify the validity of the simulation planning.