two supplementary wheels 43 are located at front and rear of the body this is a kind of gravity vehicle wheel 44 can adopt the structure of fig1 and u201c large wheel transmission u201d it is also available to adopt the wheel electromotor described in lt a sort of vehicle gt of plea know technology document 200410030581 x vehicle body connects with wheel swing supplementary wheel can run in parallel to match up turning supplementary wheel carries an elastic device which flexes up and down following pressure the wheel is unnecessary to touch the ground or slightly touch or touch the ground in discontinuity or only one supplementary wheel touch the ground only need one main wheel can realize turning and braking to use two main wheels at same time can brake or decelerate the vehicle fig2 28 u2014 fig2 is the left view diagram fig2 is the top view diagram of fig2 an integrated vehicle 18 carries a rack beam 45 an electromotor 170 and trail wheels 46 electromotor 170 is located at the bottom of the rack beam 45 and on the top of integrated vehicle 18 electromotor 170 drives gear 17 and pushes the vehicle 18 forward trail wheel 46 plays the role of balance such vehicle can also be unmanned or remote controlled the body 16 can optionally include a compressed air tank 47 details of the compressed air tank 47 are described in fig3 35 fig2 pendulum shaft 503 shows a structure of bend and concave wheel axis 504 is.