The invention relates to a method for machining a surface of an area to be machined using an autonomous mobile robot. According to the embodiment discussed here, the method includes the steps of controlling the robot in order to machine the area according to a first machining pattern, monitoring a region in the surroundings of the robot, wherein the region has a fixed position relative to the robot, and controlling the robot in order to machine the area according to a second machining pattern if a reachable and unmachined region is detected in the monitored region.