An Alternative Inverse Kinematics Position Analysis for the Control of Welding Robot

Welding robot is a manipulator which is analyzed and applied widely. It’s important to obtain the values of the robot joints when the position of end-effector is settled. In the design preliminary stage, or any other stages without a manipulator or a teach pendant as the real model, it’s necessary to develop the analysis method and algorithm to obtain the configuration of robot and simulate the control process, according to the robot parameters. In this paper, firstly the inverse kinematics analysis based on analytic expressions was developed to obtain the functional expression of each joint. Then based on the expressions, the algorithm was proposed to calculate all the exact values with the position of end-effector settled. The algorithm was realized by programming in MATLAB, making it easy to get the solutions of each joint, which provided the basic data for controlling. Finally we presented the control functions during a specific trajectory as example, considering the principle of minimum energy consumption. The result of this method is proved to be correct and the procedure is effective and fast. With the method one can analyze all the admissible configurations of the robot conveniently and obtain the control functions of robot joints to keep the end-effector in a specific trajectory.