Improvement of both handling stability and ride comfort of a vehicle via coupled hydraulically interconnected suspension and electronic controlled air spring

The trade-off between handling stability and ride comfort is a disadvantage for the bus fitted with passive suspension due to its high center of gravity and heavy load. A novel suspension configuration with both hydraulically interconnected suspension and electronic controlled air spring is created to handle this conflicting requirement. The proposed whole vehicle system model has three subsystems: a 9-degree-of-freedom vehicle multi-body model, hydraulically interconnected suspension model, and electronic controlled air spring. The electronic controlled air spring comprises an air spring and an auxiliary air chamber, and its height can be adjusted by a fuzzy controller. Then, analytical work is performed to evaluate the handling stability and ride comfort of the vehicle with different suspension configurations under various maneuvers and suspension height modes. Finally, the vehicle on-road test is conducted to experimentally validate the proposed models. Both analytical and experimental results indicate that the vehicle fitted with hydraulically interconnected suspension and electronic controlled air spring can obtain high performance for both handling stability and ride comfort.