【作者】 李俊杰；

【导师】 杨波；

【作者基本信息】 武汉理工大学 ， 车辆工程， 2013， 硕士

【摘要】 随着高速公路的发展、道路的拓宽、车辆数量的增加与动力性能的日益增强,事故发生率也在高速上升。道路安全问题在当今社会已经引起了国内外公民与学者的高度重视。侧翻事故是众多常见安全事故类型中的一种,并且对车辆以及人员的伤害度极大。质量大、重心高的重型车辆,由于其操纵稳定性与侧倾稳定性较差,是最容易产生侧翻事故的车辆类型。虽然有经验的驾驶员能根据实际情况快速进行调整,有效避免侧翻发生。但有时候由于驾驶员注意力不够集中、或遇到突发情况稍作大幅度转向等情况,会使驾驶员不一定能及时预知侧翻风险而未采取有效的补救措施。所以,能提前给驾驶员警报提醒的侧翻预警系统对于重型车辆还是很有必要的。近年来国内外关于车辆侧翻预警与侧翻控制的研究也越来越多,但是大多数研究都是关于普通重型车辆或SUV,而非多轴重型车辆的。本文首先以普通重型车辆为研究对象,建立动力学模型,再扩展到五轴重型车辆进行研究。本文主要研究内容如下：首先,为了研究车辆的侧翻动力学特征,以某重型客运车辆为研究对象,以经典单轨动力学模型为基础,增加侧倾运动,建立了三自由度侧倾动力学模型,并在在Matlab/Simulink完成其仿真模型的搭建。对仿真模型进行J-Trun工况、双移线工况、鱼钩转向工况下的仿真试验,并加以验证其合理性。其次,根据五轴重型车辆单轨模型,并结合零质心侧偏角的传统方式研究了五轴重型车辆的转向关系。在此基础上结合客运巴士三自由侧倾动力学模型的建立方法建立了五轴重型车辆的三自由度侧倾动力学模型,并进行了仿真验证。文中还针对车轮转角、轮胎侧偏刚度、悬架侧倾刚度、车辆重心到侧倾中心高度、簧载质量六个敏感因子进行了关于车辆侧倾运动的敏感性分析,并得出各敏感因子的敏感性差异。最后,选择五轴重型车辆的侧向加速度作为侧翻判定阈值,并阐述了其理论依据。将侧翻预警时间TTR作为侧翻预警指标,设计了五轴重型车辆的侧翻预警算法,在Matlab/Simulink中建立侧翻预警系统模型,并验证了其有效性与正确性。更多还原

【Abstract】 With the development of highway, the road widen, the increasing number of vehicles and the growing performance of dynamic system, accident rates are also on the rise. Road safety issues in today’s society has caused attaches great importance to the citizens and scholars all over the world.Rollover accident is one of the many common type safety accidents, and it always causes great injuries to vehicles and passengers. Because of the poor handling stability and rolling stability of the heavy vehicles with big weights, high center of gravity, it becomes one of the most prone to rollover accident vehicle type. Although skillful drivers can quickly adjust according to actual condition, and effectively avoid a rollover accident. But sometimes due to the driver’s attention is not enough concentration, or sharp steering with emergency, etc., can make the driver may not be able to predict the rollover risk in time and did not take effective remedial measures. So, a rollover warning system which can give the driver alarm is very necessary for heavy vehicles.In recent years, researchers of domestic and overseas pay much more attention on vehicle rollover warning and rollover control research, but most studies are about ordinary heavy vehicles, or SUV, instead of multi-axle heavy vehicles. This paper begins with the ordinary heavy vehicle as the research object, builds the dynamic model, and then expanded to5-axis heavy vehicles were studied.The main research content of this article is as follows:First of all, in order to study the lateral dynamics characteristics of vehicle, taking a heavy passenger vehicle as the research object, based on the classical monorail dynamics model, increase the roll movements,3-dof swaying dynamics model is established. Then complete the simulation model in Matlab/Simulink. Run the simulation model for J-Trun condition, Doubleline conditions, Fishhook condition, and verifies its rationality.Secondly, according to5-axis heavy vehicles monorail model, combined with zero side-slip Angle of mass center of5-axis is studied in the traditional way of heavy vehicle steering. Combined with the modeling methods of the3-dof swaying in heavy vehicle dynamics model, complete the3-dof dynamics model of5-axis heavy vehicles, and a simulation was carried out. This paper also aimed at six sensitive factors:turning angle of wheel, tire cornering stiffness, suspension roll stiffness, the distance of vehicle gravity center to the roll center, sprung mass. Complete the sensitivity analysis of vehicle roll movement. This analysis also concludes the difference of the sensitivity of sensitive factors.Finally, choose5-axis heavy vehicle lateral acceleration as the rollover decision threshold, and expounds its theoretical basis. Choose the rollover warning time TTR as a rollover warning index, design the rollover warning algorithm for5-axis heavy vehicle, establish the rollover warning system model in Matlab/Simulink, and verify its validity and correctness.更多还原