PROBLEM TO BE SOLVED: To provide a kind of a carrying vehicle for carrying an individual (10) over ground having an uneven surface. SOLUTION: The vehicle for conveying a payload including a user includes: a. a platform for supporting the user; b. a ground-contacting module mounted on the platform to advance the user over a base-forming surface in a desired motion; c. a proximity sensor for determining whether the user is present on the device; and d. a safety switch connected to a proximity detector for preventing operation of the ground-contacting module if the proximity sensor does not determine the presence of the user on the device. COPYRIGHT: (C)2010,JPO&INPIT