【作者】 王影；

【导师】 贾启芬；

【作者基本信息】 天津大学 ， 一般力学， 2005， 硕士

【摘要】 汽车悬架通常由隔振弹簧、减振装置和导向机构三部分组成。而按控制力又可分为被动控制、半主动控制和主动控制三大类。作为新型减振器的磁流变阻尼器具有相应速度快、阻尼连续可调、功耗小、阻尼力大、动态范围广、频响高等特点,是传统汽车减振器的上佳替代品。本文首先通过对磁流变减振器的参数化模型和非参数化模型进行对比分析,指出了应综合发挥两种模型各自的优势,进而深入研究总结精确实用的数学模型,以利于减振器设计与控制器设计。接着具体通过对Bouc-Wen模型进行的数值分析,揭示了14个参数对模型阻尼力的影响,证明了通过合理有效地选择参数可设计出符合工程实际应用的磁流变阻尼器。然后运用随机理论对汽车采用磁流变阻尼器的Bouc-Wen模型进行了理论分析,对采用磁流变阻尼器的汽车悬架模型进行了模拟仿真分析,并与传统线性阻尼器进行了对比,指出了采用非线性的阻尼器模型更准确描述了汽车悬架的物理特性,而要更好地改善汽车整体的舒适性,还是要寻找优良的控制策略。继而,通过对比半主动可调磁流变阻尼控制与被动控制、主动控制和半主动on-off控制在正弦激励和随机激励下的各种性能特性,证明了磁流变阻尼器在汽车控制工程中的可行性,说明磁流变阻尼有很好的应用价值。非线性在汽车系统中可谓无处不在,而控制策略也已由传统线性控制转向非线性控制。本文接着在考虑悬架弹簧非线性的情况下,讨论了汽车的随机特性,并对FPK方程进行了展望。运用微分几何理论对非线性汽车主动悬架进行输出——干扰解耦条件的判断,得出含有非线性弹簧的主动悬架符合此条件的结论,并对此系统进行线性化,通过线性化后,对其施加最优控制得到了良好的效果。通过本文的研究,可以得出通过采用新型优良的产品,运用行之有效的控制策略,能很好地提高汽车整体的性能特性,改善乘坐的舒适性,行驶的平顺性,操作的稳定性,使得现代汽车变得更加完美。更多还原

【Abstract】 The car suspensions usually are made up of spring, damper and orientedequipment. However according to control power, it can be divided into three majortypes——passive control, active control and half active control. As a new damper,magnetorheological dampers made from the magnetorheological fluid arecharacterized by the fast response, continuously modulatory damper, low power,strong damper power, wide dynamic range, fast frequency response, etc.. Due to allthese attributes, it becomes superior substitute for the traditional dampers.First this paper points out that adopting different model to magnetorheologicaldampers for unique advantage each other, by contrasting and analyzing parametermodel and non-parameter model. Furthermore the text summarizes more accuratelyapplicable mathematic model in the interest of damper design and controller design.Secondly through analyzing Bouc-Wen model numerically,it reveals the influence ofthe 14 parameters to damper power of magnetorheological damper. Hence we candesign appropriate magnetorheological damper availably for concretely engineeringapplication. Thirdly the text studies the car suspension with magnetorheologicaldamper in the random theory and simulates the system in Matlab&Simulink.Contrasting this system with linear system, we draw a conlusion that adoptingBouc-Wen model just describe the attribute of the suspension more actually andwhich show for the improvement of the riding comfort, taking a good controll strategyis necessary. Furthermore the article discusses the responses of the car suspensionunder half active adjustable magnetorheological damper control、passive control、halfactive on-off control and active control riding on sinuous road and random road. Andin conclusion magnetorheological damper is adaptive to the car control engineeringwith excellent application value.Nonlinear lies in car system everywhere. So the control strategy have alreadychanged from linear control to nonlinear control. Continuously this article arguesabout the random attribute of the car suspension in consideration of the nonlinearspring and proceeds the outlook to the square distance in FPK equation. The textjudges the condition of the coupling solution with output and disturbance in thenonlinear suspension control system by the differential calculus. Proving the activesuspension with the nonlinear spring accord with that condition. Then after linearizedthe nonlinear system, we bring the optimization control into effect in suspension andgot the good result.Over the textual research, we can say if passing the new good product in adoption,making use of a type of control strategy effectively, the whole function characteristiccan be increased, the comfort of the riding can be improved, the stability of therunning can be enhanced. Finally the modern car can be perfect on the end.更多还原