Welding automation is the direction of welding technology development, and weld seam tracking is one of the main methods to achieve automated welding. By real-time detection of the contour and position of the weld seam, welding robots are controlled to automatically track welding based on position and geometric information. As an active measurement technology, laser vision sensing technology has the advantages of non-contact, high accuracy, and fast speed, and can be applied in real-time weld seam tracking systems.
The positioning error, processing error, and installation error of laser sensors in the process of robot automated welding are the issues. The line structure vision laser sensor obtains the shape and position information of the weld seam, and enables the robot to automatically adjust the position and posture of the welding gun to correct errors. At the same time, it adapts to a multi-layer and multi-channel path planning method for welds at different angles.
Firstly, perform hand eye calibration to convert the spatial point information of the weld bead from the visual coordinate system to the robot base coordinate system. Then scan the workpiece, complete the preprocessing calculation of the actual coordinate points through a pre-set algorithm, and adaptively adjust the pose of the tool coordinate system to compensate for the deviation; Finally, based on the characteristic parameters of the processed weld groove and the welding process requirements, plan a multi-layer and multi pass welding path to complete the welding.
The working mode of the weld seam sensor
One type is mainly used in the welding process to automatically detect welding conditions (such as groove size, etc.) and control welding process parameters in real-time to adapt to the welding conditions at each moment, known as welding condition real-time tracking sensors. Another type is used to detect the position of components. The position of the groove or the centerline of the weld seam is used to achieve automatic tracking of the weld seam position, abbreviated as the weld seam position automatic tracking sensor.
Therefore, it is required that welding robots can quickly respond to constantly changing welding environments with stronger adaptability and intelligence. Weld seam tracking is a key technology for automated welding processes and post welding. Laser seam tracking and sensing technology plays an extremely important role in robot welding.