PROBLEM TO BE SOLVED: To provide a ground movable body, a control circuit, a measuring device, and a setting program capable of detecting recesses such as staircases, grooves, and raising safety.SOLUTION: A measuring device 3 is installed so that a depression angle forms a predetermined angle at predetermined height from a grounding point in a ground movable body 1, and distance from an installation position to a reflector at an oblique lower part or a lower part is made possible to be measured. Then, when the ground movable body 1 moves toward a travel direction F, the distance to the reflector is measured, and a safe area As, an alert area Aa, and a dangerous area Ad are set so as to determine that danger is higher as the measured distance is longer. In addition, also for a side of the ground movable body 1, the safe area As, the alert area Aa and the dangerous area Ad are set so as to determined that the danger is higher as the distance to the reflector is longer.
