The differential adjustment is automatic and involves the "minimum energy consumption principle," in which all objects on earth tend to use the least energy. For example, if you put a bean in a bowl, the bean will automatically stay at the bottom of the bowl but never on the wall. Since the bottom of the bowl is the lowest possible energy (potential energy), it will automatically choose to stay still (minimum kinetic energy) instead of constantly moving. Similarly, the wheel will automatically tend to the state of the lowest energy consumption when turning, automatically according to the turning radius to adjust the rotation of the left and right wheels.

     When turning, because the outside wheel has to pull the phenomenon, the inside of the wheel has the phenomenon of slippage, two driving wheels can produce at this time in the opposite direction from the two additional force, because "the principle of minimum energy consumption", inevitably leads to both sides of the wheel speed is different, so as to destroy the balance of the three relations, and by reflecting on the axle shaft gear axle shaft, forcing the planetary gear rotation, make the inside of the half shaft speed slow, the lateral half shaft speed is accelerated, so as to realize the difference of on both sides of the wheel speed.