A transportation vehicle and methods for transporting persons, robots or cargo, and more particularly motorized vehicles, and methods for transporting over surfaces, including surfaces such as floors, roads, paths and sidewalks, and surfaces having obstacles or inclined surfaces and for enabling the ascending or descending of stairs without tilting while supporting a user or a load on a frame. The vehicle uses horizontal extending and retracting rods and vertical extending and retracting rods to pass over an obstacle or ascend or descend stairs. The horizontal extending and retracting rods are used as mechanisms to move the first set of ground contacting modules located to the fore of the vehicle or the last set of ground contacting modules located to the aft of the vehicle in a fore-aft plane to pass over an obstacle or to position the first set or last set of ground contacting modules upon a stair to be used for ascending and descending stairs. The vertical extending and retracting rods are used to raise or lower the frame, to raise or lower individual ground contracting members and to keep the vehicle stable.