Test And Research Of Automobile Tyre Rolling Radius

When a car is running, it is very dangerous if the tyre burst. Many researching literature show that abnormal tyre pressure is one of the main reasons causing tyre burst. Large proportion of accidents are caused by the burst in our country. Tyre pressure minitor system TPMS can easily find out abnormal the tyre pressure and avoid burst accident. At present there already have products of TPMS fixed on the car in foreign countries, but there is no information of TPMS in our own country. This paper is the preliminary work of developing our own TPMS. When a car is running, the discretion of the tyre air pressure can be checked by on the change of the tyre radius. High pressure can enlarge the tyre rolling radius, so the tyre revolving number is less than the number in normal tyre pressure under the same milage, and vice versa. At the same time, load and velocity of the car have great effect on tyre air pressure. So the key to the development of TPMS is to find out main factors affecting the tyre rolling radius and their changing interrelations. At present, there is no mature model of researching the change of tyre rolling radius all over the world, and there is no authoritative saying on the rolling radius changing rule when the tyre is rolling. This paper puts forward the "rolling radius" method, through the different revolving number in a given milage to judge whether the tyre pressure is normal. Aiming at the three most important factors affecting the tyre rolling radius change, air pressure, load and velocity static and dynamic tests have been carried out. Through analyzing the static and dynamic data, the interrelations among air pressure, load, tyre sinking value at static situation and the rule of relation among tyre rolling radius and changing air pressure, changing load, changing velocity at dynamic situation can be obtained. The test data obtained from this paper provide a data carrier for further establishment of tyre rolling model based on test parameters. The changing rule of affecting tyre radius under both static and dynamic situation obtained from this paper also provides certain theoretical foundation for developing TPMS.