Patent attributes
A robot includes a range finding sensor that measures a distance from the robot to an object facing a display each time the range finding sensor rotates through a predetermined angle. If a difference between a first distance previously measured and a second distance subsequently measured is a first predetermined value or greater, information is stored in a memory to indicate that a down-step is located in a direction defined by a turning angle of the robot when the first distance is measured at a position that is separated from the robot by the first distance. When rotating and moving the main casing in a direction in which the down-step is located, the robot is caused to make a pivot turn first. Subsequently, the main casing is rotated to move in the direction in which the down-step is located by a distance smaller than the first distance.