In the process of driving, the vehicle needs to change its driving direction frequently according to the driver's will, that is, the so-called vehicle steering. As far as wheeled vehicles are concerned, the method to realize vehicle steering is that the driver deflects the wheels (steering wheels) on the vehicle steering axle (generally the front axle) at a certain angle relative to the longitudinal axis of the vehicle through a set of special mechanisms. When the car is driving in a straight line, the steering wheel will also be affected by the lateral interference force of the road, and will automatically deflect and change the driving direction. At this time, the driver can also use this mechanism to deflect the steering wheel in the opposite direction, so as to restore the original driving direction of the vehicle. This set of special mechanism used to change or restore the driving direction of the vehicle is called the vehicle steering system (commonly known as the vehicle steering system). Therefore, the function of automobile steering system is to ensure that the automobile can turn and drive according to the will of the driver.