The Mechanism Design And Simulation Of Saddle-Shaped Weld Seam Welding Robot

Pressure vessel is extensively apply to industry, petrochemical, medicine, architectonics, agriculture, and other manufactures. Saddle-shaped weld seam is common weld form in pressure vessel welding, it has the irreplaceable contribution to the country economy. The weld seam welding is mainly done by manual at present, it is urgently need to develop this kind of weld welding robot because of poor working condition, low efficiency and hard to ensure the quality of welding.The article analyses the current research status of saddle-shaped weld seam at home and abroad, sets up the mathematical equations of saddle-shaped weld seam, weld slop and weld rotation under different conditions, receives the mathematical equations deflecting angle and tilting angle through coordinate transformation at last, it provides theoretical basis for the robot structure design and control.It puts forward a variety of mechanism projects that can able to complete the weld seam welding through analyzing the mathematical equations of saddle-shaped weld seam, weld slop and weld rotation, and ultimately chooses the operating mechanism for cylindrical coordinate operator, wrist for two degree of freedom centering wrist mechanism scheme of five DOF series robots. Determines the scheme of kinematic is feasible by using the method of D-H coordinate mechanism project to gets it’s motion parameters.Depends on the requirement to completed the structure design of mechanism project, we designed a type of two DOF centering wrist. This wrist use tow arc with common center to adjust weld torch’s inclination and rotation angles. This method actualize the decoupling control of robot, reduced the difficulty of control.Use ADAMS to build virtual proto of the robot, and proceeding kinematics analysis, to obtain the trajectory of the terminal of welding torch. Comparing with the actual trajectory, analysis the deviation between them. The experiment show that this kind of robot has allowable deviation, can satisfied the design requirement.