Jing Fengshui

RGB-D sensor-based auto path generation method for arc welding robot

In this paper, an auto path generation method for arc welding robot is proposed by using a RGB-D sensor. From the generated 3D point cloud of the weld workpiece, the welding line is extracted and the path points of the robot are generated by an auto path generation algorithm. So the torch tip of the arc welding robot would walks along the welding line. This path generation module is added to current widely used ordinary arc welding robot while not changing it, used to assist people when teaching arc welding robots. This maybe eventually replace operator by automatically generate the path. The detail algorithm of the recognizing space curve welding lines and the auto path point generation method are emphasized in this paper. Experimental result shows the application feasibility of the proposed method.

Servo system to control Arc length for electro-gas welding equipment

Automatic welding equipment with arc length control for electrolytic aluminum plant is designed. The servo system is composed of AC servo motor, ball screw, electro-gas (EGW) power, base material to be welded and servo controller. The welding power is installed of numerical communication port of welding current, providing information of velocity error between welding pool and gun. MIMO model of welding process is simplified into a linear error amplified. Dynamics of AC servo motor and ball screw with external load are analyzed. And a list of parameters is provided for further controlled design. The system is essentially a multi-loop control system. The internal loop of PID controller is tuned first. And then the whole system with PD controlled is tuned, so that the overshoot (σ%) and stabilization time (ts) is comfortable. At last, with the help of Simulink, arc control performance test is conducted. It proves that the system can keep arc length almost constant. This method is practical and easy to be realized for industrial application.