Disclosed is a mobile robot with a housing, wherein a memory module is coupled to the housing. The memory module can store an image file of at least one arbitrarily shaped ink mark which is human-imperceptible and forms a landmark on a navigable route. Mounted to the housing, is a detector configured to detect ink marks marked on a surface. The mobile robot includes a confidence matching system coupled to the memory module and the detector. The confidence matching system is configured to determine whether a detected ink mark is a landmark based on a comparison of the detected ink mark with the stored image file of the at least one ink mark. The mobile robot includes a navigation system coupled to the confidence matching system configured to navigate the robot through an area including the navigable route based on recognition of the landmark.
