Abstract: A method for controlling the printing of overlapping swathes, the swathes extending perpendicular to a succession of print lines; for each print line a transition is defined between one swathe and the next, with the location of the transition in the print line varying between print lines, for example varying pseudo-randomly or as a curve extending in the swathe direction.

Abstract: A method for controlling the printing of overlapping swathes, the swathes extending perpendicular to a succession of print lines; for each print line a transition is defined between one swathe and the next, with the location of the transition in the print line varying between print lines, for example varying pseudo-randomly or as a curve extending in the swathe direction.

Abstract: A system for visually pointing out locations on a three-dimensional structure such as an airframe of an aircraft includes a laser head that traverses an elongate track erected to pass through or adjacent to the structure. The laser head is traversed and stopped at various positions along the track, and from each position the laser head is calibrated by directing the laser beam onto three or more reference locations on the structure whose nominal coordinates are known in a reference coordinate system such as used in a CAD-CAM definition of the structure. The laser head is operable to determine in its own internal coordinate system the direction of the laser beam to each reference location and the distance to the reference location, and from this information a calibration is determined for relating measurements made by the laser head to the reference coordinate system.

Abstract: A system for visually pointing out locations on a three-dimensional structure such as an airframe of an aircraft includes a laser head that traverses an elongate track erected to pass through or adjacent to the structure. The laser head is traversed and stopped at various positions along the track, and from each position the laser head is calibrated by directing the laser beam onto three or more reference locations on the structure whose nominal coordinates are known in a reference coordinate system such as used in a CAD-CAM definition of the structure. The laser head is operable to determine in its own internal coordinate system the direction of the laser bean to each reference location and the distance to the reference location, and from this information a calibration is determined for relating measurements made by the laser head to the reference coordinate system.