Firstly, the reason why the wheels can travel normally is theoretically because the friction between the wheels and the ground is greater than the traction force on the wheels. So where does the friction come from? Undoubtedly, it comes from the normal contact between the tire carrying pressure and the road surface. The carrying pressure comes from the sum of the weight of the vehicle itself and the weight of the cargo it carries.
When the carriage is filled with cargo or when the vehicle is empty and uphill, the lever phenomenon will occur. The rear wheels of the trailer bear the main pressure, and the front of the trailer will slightly tilt, which may cause the driving wheels to slip. The reason why skidding occurs on uphill and other similar road conditions is because the tire grip is reduced, which is commonly known as the inability to hold the car down by experienced drivers.
After this problem occurs, the slipping problem can be solved in a short period of time by adjusting the position of the cargo being pulled in the carriage, placing the cargo as forward as possible, and increasing the pressure on the driving wheels.
If the vehicle is in the same type of vehicle, it is prone to skidding on the same or similar road sections. After measurement, it is found that the position of the towing pin is relatively forward, which may be caused by the towing pin position. If the distance from the towing pin of the semi-trailer to the front of the trailer is too small, that is, the front suspension is too small, it may cause insufficient tire grip.
