Abstract: The method according to the invention and a device suitable therefor are used for controlling various device units on a rail vehicle by means of lateral copying. By additionally using available information from the track channel (12), for example, of check rails (30) or wing or switch rails (31, 33), device units for machining and/or analyzing laid tracks (10) can more precisely follow the actual rail profile, in particular in the region of rail gaps or railroad crossings. The lateral copying of the rails (10) and the copying of the rest of the track channel (12) takes place with at least one dual-action or a plurality of single-action or dual-action scanning or sensor units (20).