Mobile robot and visual navigation method of the same

Disclosed are a mobile robot and a controlling method of the same. The mobile robot is capable of reducing a position recognition error and performing a precise position recognition even in the occurrence of a change of external illumination, through geometric constraints, when recognizing its position with using a low quality camera (e.g., camera having a low resolution). Furthermore, feature points may be extracted from images detected with using a cheap camera, and the feature points may be robustly matched with each other even in the occurrence of a change of external illumination, through geometric constraints due to the feature lines. This may enhance the performance of the conventional method for recognizing a position based on a camera susceptible to a illumination change, and improve the efficiency of a system.