According to the requirements of automobile driving kinematics, the actual wheels, roads and their mutual relations, it is shown that the left and right wheels often have different strokes at the same time during automobile driving. For example, when turning a corner, the outer wheels always travel longer than the inner wheels. In addition, even if the car runs in a straight line, it is required that the outer diameters of the left and right wheels are different or the rolling radii are not equal due to the different vertical waveforms of the road surfaces that the left and right wheels roll over at the same time, or the different tire pressures, tire loads, tread wear degrees and manufacturing errors of the left and right wheels.