PURPOSE: To take a work even if the work is positioned aslant to a guidance line.

CONSTITUTION: A fork part 13 is directed to a work 61, and an unmanned carrier 10 travels rearwards along a guidance line 60. A work 61 is positioned aslant to the guidance line 60, and a traveling distance which is made up to a timing when a fork end sensor 51b detects the work 61 after a fork end sensor 51a detects the work 61 is detected, so that the unmanned carrier 10 stops. A steering angle is computed based on the traveling distance and is maintained for steering traveling. The fork part 13 is inserted into the work 61 in parallel, and the work 61 is placed onto the fork part 13. The steering angle is maintained for advance traveling, and when the carrier detects the guidance line 60, it advances along the guidance line 60.