Study And Development For The Controller Of Commercial Vehicle Suspension System

Suspension system is the important portion of vehicle; it plays an extremely important part in improving vehicle ride comfort and handling stability. The passive suspension system is only a compromise between ride comfort and handling stability, because of the spring and the damper are not controllable. But the electronically controlled air suspension can adjust its rigidity according to the state of roads and needs to carry on, so it has the remarkable effect in enhancing the automobile smooth running, the operation stability as well as reduce to the road surface destruction. The air suspensions have already been popularized in the High-grade commercial buses in many developed countries, such as US, Japan and Europe etc. However, at present our country also occupies the air suspension introduction, the digestion stage. The air suspension control strategy was researched very few, but the vehicles with air suspension are extremely optimistic in China's market prospect. Therefore it has the huge significance which launches to the air suspension performance research, the match design and the discussion of controlling strategy.In this need, this paper studies the controlling strategy of intellective air suspension. First, we analyzed the structure and alterable rigidity of the electronically controlled air suspension. Then this paper sets up air suspension model and vehicle model to establish the state equation according to moving differential equation. Then in the time domains, the author simulates three main working conditions: static state, vehicle rollover and tire blow-out. We also set up the test-bed of the air suspension to validate the model, and make the ECU of air suspension using XC164CM. The basal functions of the electronically controlled air suspension were achieved on the test-bed. Next, for the commercial vehicle rollover more an more happening, a preventing the rollover method is proposed. The method with air suspension enhances the rollover threshold and reduces the danger of the vehicle rollover. We make up the vehicle rollover model and compile the controller. From the result of the emulator, we can see the effort of the semi-active air suspension on vehicle rollover stability. Last, this paper simulated the tire blow-out, analyzed the state of the vehicle. The electronically controlledair suspension can improve vehicle ride comfort and handling stability.