Research On Motion Control Of Automatic Steel Pipe Spiral Weld Repair Robot

With the development of industrial automation and robotics,there is an urgent need for high-efficiency and high-precision automated pipe end grinding equipment for spiral weld pipe of the end grinding of large petroleum steel pipes.At present,this field is mainly based on the semi-automated method of rough grinding by machine + fine grinding after,which not only has low efficiency,high scrap rate and bad quality of regrinding,but also endangers the health of operators.To solve the grinding technical problems,a weld grinding robot integrating automatic inspection and grinding is designed on the basis of summarizing the development experience of weld grinding.This paper adopts the offline JBI + online data pre-updating method based on Lab VIEW platform and applies the Euler angle method to realize the dynamic continuous motion of the robot arm to solve the motion control problem in the grinding trajectory.The main research contents of this paper are as follows.Communication scheme design and planning the motion control process.In order to realize the motion control in the grinding process based on Lab VIEW,communication between Siemens PLC and Touch screen,free port communication between PLC and Lab VIEW control module,and communication between YRC1000 controller and NI controller are established to lay the foundation for the motion control,data transmission and signal interaction of the whole system;and the overall grinding motion flow is planned and designed.Robot kinematics and trajectory planning.Establish the Yaskawa GP-180 robot arm linkage coordinate system by D-H method,build the robot kinematic model,and analyze the forward and reverse kinematic derivation process.The kinematic simulation is carried out in matlab using robotics toolbox to verify the correctness of the forward and inverse solutions.Combined with the spiral welded pipe production process,the robot arm linear,circular and spiral trajectory simulation is carried out to verify the feasibility of Euler angle interpolation method.Based on motocom32 secondary development package in Lab VIEW to complete the robot arm linear motion,pipe end identification,circular arc motion by offline JBI + online data pre-update,and the spiral motion program design by dynamic continuous trajectory control.System testing and experimental verification.Complete the human-machine interaction interface design of the trimming robot,Lab VIEW detection interface design,robotic arm position data transmission function tests,system integration and installation debugging.Experiments show that the operation process of each module communication function is normal and the motion control trajectory is correct.The key motion of the robot is stable and coherent,and the overall motion process is in line with the production process.After three months of continuous operation,the equipment was popularized and applied in the CNPC branch.Experimental results verified that the dynamic continuous motion control of the robot arm proposed in this paper can be realized,the motion process is continuous and smooth,and the equipment can complete the automatic inspection and grinding of the weld seam with high grinding accuracy.