DSP-based self-organising fuzzy controller for active suspension systems

This study proposed a self-organising fuzzy controller (SOFC) for controlling an active suspension system to evaluate its control performance. During the control process, the SOFC continually updated the learning strategy in the form of fuzzy rules. The fuzzy rule table of this SOFC could be initially set to zero. This not only overcame the difficulty in finding appropriate membership functions and control rules for designing a fuzzy controller, but also solved the database problem where the fuzzy rules of a fuzzy controller, once determined, remained fixed and could not suitably regulate them in real time to optimise the dynamic response of the system required to gain the desired control performance. To demonstrate the applicability of the proposed SOFC for active suspension systems, a quarter-car hydraulic-servo suspension system was designed and constructed to evaluate the feasibility of active suspension control. Additionally, to conform to real-time application requirements in the vehicular industry, the SOFC was implemented with a digital signal processor to control the hydraulic-servo suspension system so that the control performance could be determined. The SOFC has shown a better control performance in suppressing the vibration amplitude of the vehicle body for enhancing the structural safety of the vehicle and increasing the life of the suspension system. It also effectively suppressed the amplitude of the vehicle body acceleration and reduced the tire deflection for improving the ride and the handling quality of a vehicle better than a passive control, as verified in experimental results.     

山区高速公路坡面荷载的动态效应与实测研究

为了获取公路陡坡路段荷载对路面结构的动态效应,为理论计算分析和试验分析提供可靠的参数,利用自主开发的轮胎对地压力动态分布实时测量装置,进行了不同车型、不同载重、不同车速和不同纵坡条件下坡面轮胎接地压力的动态测量,得出了不同速度下坡面轮胎接地压力的分布及其变化规律。结果表明,高速运动状态下,重载货车轮胎接地形状近似于矩形,车速越高接地形状接近矩形的相似程度愈高;随着车速提高,接地压力的分布形式从凸起型分布逐渐向鞍型分布演变,接地压力峰值逐渐减小;运动状态下,车辆轮胎接地压力在行进方向上呈半正弦波分布,在横向上表现为非均匀分布。     

捷豹XF轮胎压力灯亮的故障诊断与排除

从捷豹XF轮胎压力灯亮的故障入手,详细阐述轮胎压力监控系统的结构组成及工作原理,并根据故障现象,深入分析故障原因,最终排除故障。     

废胎胶粉掺量对橡胶沥青及混合料性能的影响分析

沥青中掺入废胎胶粉可改善沥青的各项性能指标,并增强沥青混合料的高温稳定性和低温抗裂性。在基质沥青不变的条件下,随着废胎胶粉掺量的增加,橡胶沥青的旋转粘度、针入度、软化点、低温延度和弹性恢复增大,橡胶沥青混合料的动稳定度和低温破坏应变也相应增大。     

车载声强（OBSI）轮胎/路面噪声测试

随着城市的发展,轮胎/路面噪声已经成为主要噪声,根据《应用OBSI方法进行轮胎/路面噪声测试的标准方法》美国ASTM（美国材料实验协会）暂行标准研发了测试设备,采用测量声级计“A”计权网络, 记录规定测量时间T内A声级的能量平均值,用噪声能量按时间平均方法来评价噪声的影响,实现了实时量测分析评价路面／轮胎噪声,同时采集车辆速度、温度、方向等相关信息,测试过程中不受环境噪声、风噪声干扰,可用于对不同车辆车速、不同路面结构型式及不同轮胎种类所产生的轮胎／路面噪声进行量测比较,较为精确的评价路面噪声特性,是一种较为理想的轮胎／路面噪声室外测试。     

Analysis of handling performance based on simplified lateral vehicle dynamics

In this article, the analysis methods for vehicle handling performance are studied. Using simple models, dynamic characteristic parameters such as yaw, natural frequency, and the damping coefficient of a vehicle can be theoretically formulated. Here, the vehicle is simplified by a bicycle (single-track) model, and the tire is modeled by an equivalent cornering stiffness and first order lag. From the experimental road data, the tire model parameters (equivalent cornering stiffness and time lag constant) are extracted. These parameters are then inserted into the theoretically formulated equations of dynamic characteristic parameters. For the purpose of validating the efficiency of the suggested methods, experimental road tests (where the cars have different handling performances) are performed. The results show that vehicle handling performance can be sufficiently represented by the suggested dynamic characteristic parameters. So, it is concluded that the proposed method has practical use for the development of new cars or for the comparison of similar cars since the evaluations of the vehicle handling performance can be efficiently determined by the suggested dynamic characteristic parameters.     

A two-dimensional tire model on uneven roads for vehicle dynamic simulation1

This study proposes a comprehensive analytical tire model for handling and ride comfort in low frequency ranges. A contact algorithm that is developed in this study provides a two-dimensional contact pressure distribution on even and uneven road surfaces with reasonable computational cost. Shear stresses and strains during cornering and braking are estimated by direct measurement of tread deformations. The model is validated against experimental force and moment data for general handling simulations. Cleat tests are also conducted and validated under different forward velocity and vertical load conditions for a tire vibration study.     

废旧轮胎加筋土高陡海堤数值模拟分析

将废弃轮胎利用到水运工程海堤建设中,通过通用有限元软件ADINA对在浪荷载与水荷载共同作用工况下轮胎加筋土高陡海堤与未加筋海堤σ(应力)-ε(应变)状态进行对比分析,通过数值模拟应用实例可以看出:轮胎加筋土海堤不仅σ(应力)-ε(应变)明显减小,而且达到了轮胎废弃物的二次利用,是一种实用简单可行的方法。     

全钢子午线轮胎加强层帘线角对胎圈部位性能的影响

子午线轮胎有着节能、耐用的优点。使用Abaqus有限元软件建立三维有限元轮胎模型并通过将有限元模拟计算结果和实际实验数据对比,验证了模型的正确性。在此基础上,探究了加强层帘线角对胎圈部位应力影响,结果表明:在充气和垂直载荷下,随着帘线角的增加,胎体与加强层端点最大应力、应变能均出现先增后减的趋势。垂直载荷下胎圈部位的刚度随着帘线角增加而一直减小。拟合出了出垂直载荷最大应力、应变能和加强层端点下沉量随帘线角变化的函数。计算得到40.7°的帘线角能够大幅降低加强层端点处的应力、应变能,同时对该处的刚度影响较小。研究结果可为选用适合的加强层帘线角以保证节能和负载的同时减少早期破坏提供理论依据。     

绿色轮胎推广应用政策建议

我国道路运输车辆保有量巨大,发展和逐步推广使用绿色轮胎,是我国深入推进交通运输节能减排和生态文明建设的重要领域和关键环节,论文通过分析绿色轮胎在道路运输行业应用的机遇及问题,并以12 m营运客车为例对绿色轮胎进行成本效益分析,总结提出了绿色轮胎的推广应用思路和建议。