Control method for portable welding robot, welding control device, portable welding robot, and welding system

A welding control device configured to control a portable welding robot that has a guide rail set with respect to a workpiece having a corner portion and that moves on the guide rail to perform arc welding to the workpiece, the portable welding robot including a welding torch and a movable portion that moves the welding torch in a welding direction, the welding control device comprising:

• a torch position determination unit that determines a torch position on the workpiece;
• and
• a torch angle calculation unit that calculates a torch angle at the torch position, wherein
• the torch position determination unit determines the torch position on the workpiece,
• the torch angle calculation unit calculates the torch angle at the torch position, and
• the torch angle is controlled based on the calculated torch angle,
• wherein the torch angle calculation unit calculates the torch angle based on workpiece information, guide rail information, and position information of the workpiece and the guide rail, including calculating the torch angle based on a radius of curvature at the corner portion of the workpiece and a radius of curvature at a curved portion of the guide rail at the torch position, and
• wherein the movable portion controls the torch angle such that the torch angle at a straight line portion and the corner portion of the workpiece is substantially constant with reference to the torch angle at the straight line portion of the workpiece.

A portable welding robot control method using a welding system including a portable welding robot that has a guide rail set with respect to a polygonal box column and that moves on the guide rail to perform arc welding to the polygonal box column, and a welding control device that controls the portable welding robot, the portable welding robot including a welding torch and a movable portion that moves the welding torch in a welding direction, the welding control device including a torch position determination unit that determines a torch position on the polygonal box column and a torch angle calculation unit that calculates a torch angle at the torch position, the portable welding robot control method comprising:

• determining the torch position on the polygonal box column by the torch position determination unit;
• calculating the torch angle at the torch position by the torch angle calculation unit;
• and
• controlling the torch angle by the movable portion based on the calculated torch angle,
• wherein the torch angle calculation unit calculates the torch angle based on workpiece information, guide rail information, and position information of the workpiece and the guide rail, including calculating the torch angle based on a radius of curvature at a corner portion of the workpiece and a radius of curvature at a curved portion of the guide rail at the torch position, and
• wherein the movable portion controls the torch angle such that the torch angle at a straight line portion and the corner portion of the workpiece is substantially constant with reference to the torch angle at the straight line portion of the workpiece.