Abstract: A self-traveling machine incorporating a plurality of drive mechanisms each comprising a combination of a crawler unit having an endless belt and a road wheel. The drive mechanisms makes it possible for the machine to travel on and along a stairway and a rough surface ground by actuating the endless belt, for the machine body to be raised from the ground surface by angularly moving the crawler unit into a vertical position with a free end thereof directed onto the ground, and for the machine to stride over an obstacle on the ground by turning the crawler unit thereover from one side to the other side of the obstacle. The machine also includes a steering mechanism for changing the direction of said combination, with the result that the machine is easily steered to change the direction with reduced friction against the ground surface when the crawler unit is being orientated vertically upwardly.