Path planning process for a mobile unit to face machining

A path planning process is disclosed for surface treatment machines, for example cleaning machines in a supermarket. Potential path sections are first generated, starting from boundary lines of obstacles or the working surface and set like concentric circles parallel to these boundary lines and separated by the width of the treatment machine. These potential path sections are then heuristically subdivided, for example by manoeuvring marks determined on the basis of the manoeuvrability of the mobile unit, and interconnected by partial paths. The path sections are then evaluated by means of a cost function which takes into account the distances, the already treated surface and the manoeuvrability of the unit, and the most cost-effective path is set up as a planned path for the mobile unit. The path sections between manoeuvring marks are preferably recorded as graph edges and the manoeuvring marks as nodes, and are evaluated by means of known evaluation methods in order to generate optimum graphs. The invention has applications in the field of cleaning robots for supermarkets, lawn mowers, painting machines and the like.