Strain correction of the welding line due to thermal expansion is an indispensable function for robot welding. WeldPath-1 eliminates this strain and achieves welding along the correct welding line. When welding according to the teaching (teaching) point, advance the torch as taught to the first point, project a line laser to a point several centimeters away from there (red line on the left in the figure below), and with respect to the welding direction (Z coordinate). The cross section (X, Y coordinates) is imaged with a camera and the coordinate values ​​are measured (optical cutting method). This allows you to correct the point coordinate values ​​in real time. For a V-shaped groove, find the center point PC from P0 (left turn point) and P1 (right turn point).

At this time, P0 and P1 can be obtained from the shape of the cross section of the groove. The coordinate values ​​are calculated from the image by taking the red light projected from the laser with a camera. Note 1) Applying this method to teaching enables direct teaching.