Suspension is a key component in the vehicle system, which has played road vibration transmission and attenuation role in the improvement of vehicle ride comfort and handling stability occupy a key role. With the increasing demand for comfort, air suspension, developed rapidly. The traditional mechanical height air suspension valves, namely, by a high degree of valve opening adjustment charge and discharge air bag air spring air, the response is slow to respond to low accuracy. As the sensor technology and active control technology, electronic control system gradually replaced the traditional mechanical control system, greatly improving the operation accuracy and responsiveness. In the electronic controlled air suspension (Electric Controlled Air Suspension, ECAS) areas of research, control strategy has been a hot spot. According to the structural complexity of the suspension system, real-time changes, combined with fuzzy control does not depend on the characteristics of an accurate model, fuzzy controller designed to control air suspension, designed to improve vehicle ride comfort and handling stability. First, the charge and discharge air of air springs, air spring stiffness by a high degree of valve opening and closing time and the relationship between the stiffness of air spring and fitting height and charge and discharge curves of air time for the air suspension control provide the basis for the design of the system.Secondly, according to Newtonian mechanics and the state space theory, air suspension, two degrees of freedom 1 / 4 car model and eight degrees of freedom vehicle model. Real vehicle test results by comparing the results with the simulation to verify the correctness of the model, the rear suspension control system design build basis. Again, the design of air suspension control system, for eight degrees of freedom vehicle model, were established straight, turning traffic, acceleration / braking three typical driving conditions of the fuzzy control strategy, and in the MATLAB / SIMULINK simulation environment . Simulation results show that the control strategy can effectively improve vehicle ride comfort, handling stability and ride comfort. Finally, in the structures of the 1 / 4 of vehicle air suspension test rig to test, test results show that the fuzzy control applied after the body center of mass vertical vibration acceleration is worth to a significantly reduced ride comfort is improved.
Key words: electronically controlled air suspension, fuzzy control, body acceleration, simulation, test
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