Research On Coordinated Motion Of Arc Welding Robot And Positioner

welding robot workstation has become increasingly unable to meet the demand of the current work. Therefore, research and application of the robot-positioner cooperative welding operation has become the development trend in the field of welding, Specific algorithm to achieve coordinating welding is one of the hot topics of current research. In this thesis, using a six-DOF welding robot and a two DOF positioner workstations as the research object, have a in-depth research in cooperative ship-welding of complex curves space by off-line programming. The algorithm of the coordinating welding robot-positioner workstation on off-line programming has been completed. The main work is summarized as follows:(1) For the problem of the robot inverse kinematics algorithm, In this paper, a algorithm for the inverse kinematics calculation of 6-DOF serial welding robot based on geometry have been proposed. Based on the actual working conditions of welding robot,combined with the shape and position of 2, 3-link with the positive and negative of the fifth joint angles, the inverse kinematics solution is divided into four categories,rounding no meaning, and the remaining work of various types of correspondence A robot form, so each category has a clear geometric meaning, then one groups of closed-form solutions can be gained, simplifing the complex trajectory planning.Meanwhile coordinates of 2R positioner is used to define by non-standard DH method,simplifies the inverse solution algorithm positioner.(2) Reference the idea of digital discrete, to discrete space curve welds, proposed the weld coordinate as a link, to open the robot-positioner workstation closed chain coordinates system, one side is open chain robot coordinate system, one side is open chain positioner coordinating system, the robot-positioner coordinating operation is non-master-slave relationship, and then do solver to two open-chain, the realization of robot-positioner workstations decoupling, reducing the complexity of the coordination of welding(3) For example, to apply more widely ellipsoidal head and pipe welding, with five parameters to describe the position and orientation of pipe relatively ellipsoidal surface head, establish parametric equations intersecting line of its space, get the whole seam curves and its discrete, planning corresponding time series weld discrete points, to ensure the uniformity of the welding speed. Get with the Matlab software to calculate each discrete point coordinates welds, ideal for points welding each discrete state(ship welding)under the coordinating robot-positioner workstation to solve various joint angles, and then planning the joint trajectory of positioner, output of each joint angle based on the time of a text file, use Creo Parametric 2.0 software for the entire positioner workstation modeling and assembly, kinematics simulation model the angle of the text file is loaded into each corresponding axis, the simulation results show : algorithm for the inverse kinematics calculation of 6-DOF serial robots based on geometry that very high accuracy of the algorithm is verified;robot and positioner speed of each joint is smooth and continuous,With the continuous progress of the process of welding automation, the tasks thatthe welding robot have to complete have become increasingly complex and the singlethe algorithm is easy to realize the coordinated movement.