Abstract: A method for updating a map of the surrounding area wherein the map is used when controlling a transportation vehicle. The transportation vehicle attempts, when travelling along a carriageway, to detect a landmark recorded in the map of the surrounding area using sensors. In response to the transportation vehicle being unable to detect the landmark using its sensors, the transportation vehicle prepares a proposal for deletion which is sent to an external central computer. The proposal for deletion is examined in the external central computer and deletes the landmark from the map of the surrounding area in response to the proposal for deletion being verified. In the method, information regarding a visibility range for the landmark is entered in the map of the surrounding area specifying at what range the landmark is visible from a road permitting a more effective detection of landmarks.

Abstract: Welding equipment for plastic plates and the like includes a support. First and second longitudinally extending spaced parallel clamping tables are movably mounted to the support so that the tables may be moved towards and away from each other. First and second clamping beams are provided. Each beam overlies one of the tables and is movable therewith and each beam has a first and portion pivotally associated with one of the tables. A lock system extends from each of the beams and cooperates with another lock system associated with the support. The lock systems permit the beams to be independently pivoted relative to the support. A heated blade is movably positionable between the tables.