Robotic Weld Seam Correction Control System Based on Visual Sensing

Abstract

Regarding multi-pass weld seam tracking for industrial robots, a robotic weld seam correction control strategy is proposed based on visual sensing and the corresponding visual sensing weld seam correction control system is established. The system mainly consists of two subsystems:Visual sensing acquisition and calibration system, and robotic weld seam correction control system. Placed together with the welding torch, the industrial camera can obtain the groove or weld images in real time. The operators can observe the monitor software screen, which is designed by Windows Forms, to judge whether the welding torch deviates from target beyond the allowable range. If so, a correction command will be sent to a programmable logic controller (PLC) from the control panel; the PLC will send a control signal to the robot controller; the robot will read the information flow from the robot sensor interface (RSI) to convert the signal from PLC into the robot end offset which can be executed by the robot; in such way, the welding gun can be adjusted to a proper position to achieve weld seam correction control. During the verification test, the system is sensitive and has a reasonable accuracy in weld seam correction; the system works smoothly and steadily with good weld formation during the whole process.