Study On The Identification Of Automobile Driving Road Condition And Control Method Of Electrorheological Semiactive Suspension System

The viscosity and yield stress of ERF changes rapidly with the change of electric field intensity, moreover, this change is continuous and reversible, so ER technology has opened up new ideas of developing a new generation of automotive semi-active suspension system. However, restricted by the identification of driving road condition, Real-time optimal damping ratio mathematical model of the suspension system, damping characteristic control law of ERF shock absorber, and so on,there has not been continuously controlleed ER semiactive suspension system of real-time optimization damping match under different driving conditions. At present, most of them are shift-selected, costly and hard to be widely used. With the development of auto-industry and the increase of driving speed, higher requirements of dirving safety and riding comfort are put forward. In this paper, some research was conducted, aiming at the problems. The innovations are as follows:(1) With ride vibration analysis based on 1/4 model of vehicle suspension and the model of damping characteristic simulation,and the relation of body vibration acceleration, travel speed and vehicle parameters, the identification model of driving road condition was built, based on vibration acceleration and travel speed.(2) With vehicle smoothness analysis, vibration acceleration and wheel dynamic load, the joint optimal objective function of damping ratio was established;by constraint of suspension dynamic flexibility, the model of real-time optimization damping ratio of semiactive suspension system was deduced.(3) With mechanics performance analysis on ERF under the action of an applied electric field, the study on rheological properties of ERF in damping channel using parallel plate model was carried, and the damping characteristic mathematical model of ERF shock absorber, based on electric intensity and vibration velocity, was built.(4) With the real-time optimization damping match as the controlling target, the control law of electric intensity in different driving conditions was established, based on the damping characteristic mathematical model of ERF shock absorber.The computer simulation analysis shows that the model of real-time optimization damping ratio of semiactive suspension system and control law can meet the requirements of driving safety, riding comfort and manipulation stability. This research has important theoretical and application value for the design and development of ER semiactive suspension.