Study Of Fuzzy Control For Automobile Engine Vibration Isolating System Based On The Magneto-rheological Damper

The engine connected to the car body by mount, engine is the source of vibration, body is the target of vibration isolation, which requires engine mount effective absorb or attenuation vibration. There are certain limitations about the conventional rubber mount in the isolation characteristics,the engine mount requirements of the low dynamic stiffness on high-frequency vibration and damping of high on low-frequency vibration is actually a pair of contradictory body. Therefore,a general isolator is unable to meet the engine mount of the special requirements. As automobile engine mounts achieve real-time conditioning control of magneto-rheological damping using magneto-rheological damper technology,controllability with a strong response to the speed and low power consumption, making the engine on the isolation system Fuzzy control has become necessary.In this paper, the methods of theoretical analysis, numerical simulation and bench testing are applied to study.On the basis of the analysis of the source of vibration to automobile engine, test study to rubber mount and magneto-rheological damping of the static and dynamic characteristic, as well as the dynamical model established of the engine vibration isolation system, The design of the fuzzy controller for the MATLAB / Simulink simulation and test study.Through the studies, containing the excitation of the engine power input model , finding out the engine vibration of the law and rubber mount vibration parameters of the changes law and the changes relationship between the MR damper vibration damping force, frequency and the input current . At the same time, the rate of transmission of power due to the actual complexity of the operation, only as a theoretical analysis of the effects of isolation, based on the parameters of four-terminal method of acceleration Vibration Level Difference exits the characteristics of measurable and easy to operate, which makes evaluating the isolation effect of vehicle engine mounting vibration is possible.Finally, on the basis of the establishment of the magneto-rheological damping vibration isolation system dynamics model,the combination of theory of analysis and the actual experience , bringing up a fuzzy control strategy about isolator has demanded a large rigidity and a large damper on low-frequency vibration, when high-frequency vibration, requirements appropriate Damping and stiffness of the small,based on such a fuzzy control strategy, designed to two-input ,single-output fuzzy controller based on the frequency of vibration,dynamic exciting force for the import, control current for export, which had a MATLAB / Simulink simulation analysis,and the whole engines trial in different conditions,the results show that fuzzy control strategy based on the magneto-rheological mount of the effects of vibration isolation is better than rubber mount.