Mechanism Design And Motion Control For Intersecting Line Welding Robot

With the development of welding robot, more and more automated equipments replace the workers to complete welding tasks. However, the existing welding robot system can't satisfy the requirement of pipe inserting welding for the complex structure of the intersecting line, even in some case, welding tasks is completed by handwork. In order to reduce the labor intensity and to improve the welding quality, a new type of intersecting line welding robot is needed.Based on the analysis of civil and abroad research condition of intersecting line welding machine, this paper analyzes the characteristic of the intersecting line, and established the intersection model and intersecting line equation under the bias offset. According to the features of intersection, the paper refined the robot function at each degree of freedom. By comparing the joint coordinate robot and cylindrical coordinate robot, the paper established the equations of two types of structure, and then obtained a positive solution and inverse solution of the equations. Compared with the equation form, the single variable equation is chosen to describe the robot movement, and determined one kind of transversal path movement decoupling organization form by using the circular cylindrical coordinate organization to be the operation machine.By analyzing the relationship between welding torch and weld profile, combined with the torch welding work angle and walk angle, two degree-of-freedom anti-spherical robot wrist mechanism is researched. The new type of wrist consists of two circular tracks, which is realized by rotate mechanism and link mechanism. The torch installed at the end of the wrist can move at the fixed point to satisfy the independent control of the torch angle and travel angel.On the basis of the hardware's foundation, PMAC card is connected with motors. Under the developed environment of Boland c++ builder, by link with PComm32PRO dynamic link storehouse, we designed the practical direct-viewing operation contact interface, which can revise and store some variable parameter.The robot was designed by using PRO/E software. Kinematics simulation is realized in the mode of"mechanism", the accuracy of motion equations is checked to make sure the structure of the robot is reasonable.Through the welding experiment, the robot is tested when it works. The result of the experiment showed that the robot performed well when the computer sends the program to the robot system. The robot moved with gun control and weld path control independently.