The Dynamics Stability Judging Method for a Gantry-type Welding Robot

In order to improve the dynamic performance of gantry-type welding robot, this paper introduces the structural dynamics model and Lyapunov stability criterion of the gantry-type welding robot frame with nine degrees of freedom. The dynamic equations of the welding robot satisfy the Euler–Lagrange form, and the calculation index of welding robot Lyapunov stability is judged by matrix eigenvalues. Combining with the specific design parameters of an industrial welding robot, the motion stability of the gantry-type welding robot frame and the displacement response of the welding torch are analyzed. The influence of the change of the frame design structure on the stability of the welding torch for end effector of welding robot is discussed, furthermore, the improvement direction of vibration damping and anti-interference of welding robot system is pointed out. Finally, the dynamics simulation of the optimized gantry-type welding robot end effector is carried out by using ADAMS software, and the torque variation curve of the end effector is obtained, which provides a strong basis for the selection of motor models and the design of control system.