In order to make the steering wheel have the characteristics of light steering, accurate steering and stable running, four parameters are designed on the steering wheel, including the kingpin inclination Angle, kingpin rear inclination Angle, wheel camber Angle and wheel front axle, which are collectively referred to as front wheel positioning. It is a set of parameters that install the steering wheel into a certain static geometry Angle and size. In these four parameters, the first two terms are guaranteed by the basic parts of the car, generally there will be no major changes.

The original parameter value is changed due to the deformation and wear damage of the frame, axle and steering mechanism of the vehicle in use, resulting in misalignment of the front wheel positioning (mainly the camber Angle and the front beam). When the vehicle is running, the steering wheel will produce transverse slip while rolling forward, which is what we call lateral slip. The sideslip test bench is mainly used to measure the sideslip caused by the wheel camber and the front beam. When the vehicle with the front beam but no wheel camber passes through the sideslip, the side slide slides outward. When the vehicle with wheel camber but no front beam passes through the sideslip, the side slide slides inward.

The unit of lateral slip is defined as m/km, which means that the sliding plate displacement of 1m is caused by the car moving forward for 1000m, that is, a basic lateral slip unit of 1m/1km. Sideslip tester is actually will be 1000 or 1000 times 1000 m precision narrow special around (displacement) of the road, for example: the lateral slide effective length is 1000 mm (equivalent to 1000 m narrowed 1000 times), when the car front wheel side of straight line too skateboard makes lateral slide displacement towards the direction of the direction perpendicular to the car for 1 mm, we say that the car sideslip quantity is 1 mm/m, if the molecular denominator of this value multiplied by 1000, it into standard sideslip quantity 1 m/km.

The movement direction of the side skateboard is determined by the side slip direction of the wheel. If the side slip caused by the front wheel camber dominates, the side skateboard moves inward. On the contrary, if the side slip generated by the front beam dominates, the side slide moves outward. Therefore, the value measured by the sideslip test bench has both direction and quantity. It can be seen from the above that the side slip test bench is composed of two dimensional precision left and right sliding side slides and displacement sensors. In order to reduce the sliding resistance of the skateboard, the four corners under the two skateboards are equipped with rolling bearings. According to the mechanical structure, the sideslip can be divided into single plate type and double plate type.