Experimental Investigation and Semi-Active Control Design of A Magnetorheological Engine Mount

In this paper;the dynamic characteristics of a semi-active magnetorheological fluid(MRF)engine mount are studied.To do so,the performance of the MRF engine mount is experimentally examined in higher frequencies(50~170 Hz)and the various amplitudes(0.01~0.2 mm).In such an examination,an MRF engine mount along with its magnetically biased is fabricated and successfully measured.In addition,the natural frequencies of the system are obtained by standard hammer modal test.For modelling the behavior of the system,a mass-spring-damper model with tuned PID coefficients based on Pessen integral of absolute error method is used.The parameters of such a model including mass,damping ratio,and stiffness are identified with the help of experimental modal tests and the recursive least square method(RLS).It is shown that using PID controller leads to reducing the vibration transmissibility in the resonance frequency(=93.45 Hz)with respect to the typical passive engine mount by a factor of 58%.The average of the vibration transmissibility decreasing is also 43%within frequency bandwidth(50~170 Hz).

基于6σ的汽车发动机半主动悬置稳健性优化设计

针对一款汽车发动机控制节流孔式半主动悬置,建立其集总参数模型,通过灵敏度分析方法确定优化变量,以不同模式所处区间的力传递率最小为目标,采用遗传算法对其集总参数进行了确定性优化。考虑到加工制造误差导致的悬置性能变化,为提高产品的可靠性,采用蒙特卡洛法对确定性优化结果进行稳健性了分析,并运用6σ方法对半主动悬置进行了稳健性优化。研究结果表明:在允许的设计空间内,与确定性优化相比,基于6σ的稳健性优化设计能使半主动悬置的可靠性明显提高。