1. A robot cleaner, comprising: a body; a cleaning device operably coupled in the body and configured to draw dust from a cleaning region into the body; an optical pattern sensor provided on a front surface of the body and configured to irradiate an optical pattern and generate a corresponding pattern image; and a controller configured to recognize an obstacle based on the pattern image generated by the optical pattern sensor, wherein the optical pattern sensor comprises: an optical source module configured to irradiate one or more cross-shaped optical patterns outward from a front side of the body; and a camera module configured to capture the pattern image of the region irradiated by the one or more optical patterns.