A position calibration system and method are disclosed, in which a control unit is provided to control a positioner sensing module to scan a circular positioner provided on a positioning substrate in a first direction and a second direction so as to acquire midpoints of two scanned line segments and acquire an intersection of lines extending from the two center points in a direction perpendicular to the first and the second directions as a calibration reference point, which correspond to a centroid (a center) of the circular positioner. The calibration reference point functions as a reference point for positioning the positioning substrate with respect to the positioner sensing module and is stored in a memory unit. The calibration reference point can be used as a positioning point during installation of a machine and can also be used for calibration of a position of the machine.

A robotic welding system having detection means for in one embodiment detecting a path of a ferro-magnetic, light-reflective or radioactive material traced over a weld seam, and a controller for providing machine commands to cause a torch tip electrode to move the weld seam. Alternatively the detection means comprises means for detecting and tracking a) a position in 3D space of a pointer tip which is in known positional relationship to determined GPS coordinates of a reference point on the welder when traced along a desired weld seam; b) the path of a point source of light when traced along a location of a desired weld seam; c) the path of light-reflective material traced or positioned over the desired weld seam; or d) a path of a tip of a digitized pointer object when traced along a desired weld seam. Methods of operating such robotic welder also disclosed.

Methods, machines, and computer-readable mediums for determining distance correction values of a desired distance between a laser processing nozzle on a laser processing head and a workpiece during laser processing of the workpiece are provided. In some implementations, the workpiece is scanned along a desired path of a surface of the workpiece separately by the laser processing nozzle and a measurement head arranged in place of the laser processing nozzle on the laser processing head, with a capacitively measured distance identical to the desired distance. The measurement head has a lower lateral sensitivity of a capacitance measurement than the laser processing nozzle. Respective scanned movement paths of the laser processing nozzle and the measurement head are determined. The distance correction values for the desired distance of the laser processing nozzle are then determined from the scanned movement paths determined with the laser processing nozzle and the measurement head.