Abstract: A mobile robot for and a method of producing accurate physical lay-out and reference lines or performing work on a plane surface through cartesian coordinates or angle and distance systems is provided. The mobile robot has an on-board computer, a navigation system, and an emissions system. The robot is provided with a drive, for receipt of a floppy, or an internal drive, that can be programmed by an interested party directly or from a remote location by a plug-in. The program is loaded with locations that require treatment, work or equipment positioning. The robot locates and treats the coordinates with emission means, such as an ink jet type marking system, for workmen or for directly performing work at the coordinates.