Abstract: A holder (1) for fixing a cylindrical spray can (2). The holder (1) comprises a holding unit (3) for fixing the spray can (2) with a first mechanical interface (4) for connecting a GNSS receiver (5) or prism to the holding unit (3). The holding unit (3) is adapted to hold the spray can (2) such that the GNSS receiver (5) or prism and the spray can (2) are arranged coaxially to each other. The holding unit (3) comprises a second mechanical interface (6) for releasably connecting the holder (1) to a frame (7) of a surveying cart (8).

Abstract: It is suggested to provide a line marking device having a GNSS receiver or prism for a robotic total station. The line marking device further has at least one spray nozzle and a comparator adapted to compare a detected location to a predetermined pattern. The comparator calculates a location and/or a direction error. Further the line marking device has a prompting device for providing steering information to a user. The provided information is the location and/or direction error. The at least one spray nozzle and the GNSS receiver or the prism are in a fixed spatial relation to a connecting element, which is connected or connectable to an unmovable receiving element of a cart.

Abstract: A line marking device (1) comprising a cart (2) with at least one steerable wheel (3) and at least two moving elements (4, 5). The steerable wheel (3) is rotatable around its axle (13) and pivotable such that the cart (2) is steered in a desired direction. The line marking device (1) comprises a GNSS receiver (7) or a robotic total station mounted on the cart (2). The line marking device (1) also comprises at least one spray nozzle (8), for marking a line, which is mounted on the cart and directed towards the ground below the line marking device (1). The device (1) comprises an interface mounted on the cart for a comparator to compare a detected location by the GNSS receiver (7) to a predetermined pattern. The cart (2) may comprise a motor (14) which is adapted to pivot the steerable wheel (3) towards an intended movement.