共查询到20条相似文献,搜索用时 859 毫秒
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对一辆本田雅阁2.2L轿车废气超标故障进行了诊断分析,说明了诊断步骤和方法,确定了故障原因和故障部位。 相似文献
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樊永红 《筑路机械与施工机械化》2010,27(4):75-77,81
文章介绍了机械设备发生故障后,电气故障的查找与分析方法,对分析故障原因的状态分析法、图形分析法、单元分析法、回路分析法等方法以及故障点查找的手段和方法进行了分析和阐述,对工程机械常见机械和电气设备故障的检查与排除提供了经验。 相似文献
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针对一汽大众ID.4 CROZZ纯电动车型无法直流充电故障,通过读取故障码,锁定故障范围,借助数据流分析,找出故障点,解决故障,并进一步对故障产生原因进行分析。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):347-372
This paper describes work carried out on the development of a narrow tilting vehicle at the University of Minnesota. The project had two objectives. One objective was to better understand the dynamics of two-passenger leaning vehicles. The other was to use this understanding to design and implement leaning control on such a vehicle. The desire was to make a tilting vehicle as easy, in some sense, to drive as a non-leaning vehicle. The scope of this work was fourfold. First, a model of such a system was developed and linearized to obtain a fourth-order linear model. Second, a tilt controller was designed to stabilize a tilting vehicle's unstable rolling mode. Third, the system and controller were simulated using both Simulink and a real time simulator written with Visual Basic. Fourth, and most importantly, an experimental vehicle was built and used for implementation. Comparisons were made between the simulated system and the experimental vehicle. This illustrated the limitations encountered in the simulations but also showed similarities that validated the model. Also, experimental results showed that the vehicle was stabilized well by the controller within the limitations of our hardware. 相似文献
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盾构隧道接缝漏损是诱发地面塌陷的主要因素,掌控水土流失发展规律是规避地面塌陷风险的基础和前提。基于临界漏缝宽度,针对不同漏缝位置、不同覆土深度、不同上覆水位高度进行砂土沉降规律及孔隙水压力变化规律影响因素的模型试验分析,并设计一套渗流示踪装置探究渗流场的分布情况及其流线轨迹变化规律。试验结果表明:距离漏缝竖向距离越近的砂层沉降越明显,坍塌范围由隧道漏缝周围逐渐向上扩散至地表,砂层位置越高,沉降槽越宽,由深“V”形态、浅“V”形态向“高斯曲线形态”发展。漏缝越靠近拱底,砂土表面沉降越小,孔隙水压力消散值越小;覆土深度越高,砂土沉降越小,扰动范围越窄,孔隙水压力消散值越大;上覆水位高度越高,砂土沉降越大,扰动范围越宽,孔隙水压力消散值越大。示踪流线为一系列圆弧线,5条流线均向漏缝位置流动,距离漏缝较远处水的流动速度慢,导致流线变长,示踪流线向下发展将加速贯通至漏缝流线形成。此外,通过构建隧道-砂土离散元数值模型,对渗流侵蚀过程中的砂土成拱效应及位移演变规律进行分析,揭示了盾构隧道周围砂土颗粒迁移及损失对周围环境的细观尺度影响。离散元分析表明:在接缝未发生漏损时,没有产生渗流侵蚀通道,接缝周... 相似文献
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针对城市混合交通的复杂场景图像中多目标及其参数的检测问题,提出了一种由改进的帧间差分与边缘提取相结合的算法。利用帧间差分法检测车辆的存在,对帧差图像运用统计滤波算法提取多运动目标,通过形态学方法提取并细化目标边缘,根据主边缘(轮廓)信息完成车辆定位,最终结合摄像机标定结果计算出多目标交通参数。算法避免了复杂场景的背景建模,减少了运算量。实验结果表明,该算法不仅能较为准确地检测多运动目标的参数,而且具有较强的实时性。 相似文献
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为了监测与评判道路上行驶的智能汽车的实时状态,基于研发的智能汽车的车载感知系统,包括通过视觉传感器、激光雷达、GPS定位、车载传感器系统及车载总线获取车内及周围环境信息。采用V2X通讯设备等获取路侧端雷视一体机、路侧传感器、气象传感器传输的交通信息,通过V2X通讯设备、4G通讯模块传送到云服务器并建立模糊评判模型。基于可信度的模糊推理算法对环境信息和交通信息进行融合,并以此为依据对行驶车辆的状态进行评判。首先,建立针对车辆行驶状态的模糊评判集合和各参数隶属度函数,计算出各参数的隶属度,并对行驶车辆的各个参数建立典型的行驶状态评判参数数据集合。其次,采用模糊假言推理方法,以典型的数据集合为基础建立带可信度和阈值的模糊规则库。应用麦姆德尼方法,建立与规则库的每个规则所对应的模糊关系矩阵库。以车辆行驶时接收到的车载端和路侧端信息作为输入,应用规则库规则进行带有可信度的模糊推理。然后,以相似度作为匹配度,对推理规则设定阈限,按照证据与规则的前件不相等的情况,计算结论的可信度得出结论。对结论进行冲突消解时,冲突消解的策略为取可信度高的结论。最后,应用匹配度对结论的可靠性进行验证,并在多个道路场景实时行驶的车辆上对算法进行试验验证。研究结果表明:算法对行驶车辆状态的评判与实车的状态相一致,可实现对车辆不安全状态的报警与行驶状态的干预,对保障行车安全有显著积极的实际应用意义。 相似文献
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以韶关五里亭大桥为依托,介绍了梁拱组合桥的设计与施工的新思维.详细论述该桥单排无承台变截面桩的新结构,主梁分条、分块预制组拼顶推的新工艺,主拱的三管集束式钢管混凝土拱肋,以及“先梁后拱”的施工新方法.研究成果可供同类型的桥梁设计、施工参考. 相似文献
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为解决智能车辆在车道变换过程中的路径规划和路径跟踪问题,首先,利用梯形加速度法设计了车道变换虚拟理想轨迹,该路径规划方法的适应性取决于车道变换时间、横向加速度及变化率等关键变量的约束条件,因而对各关键变量之间的数学关系进行了定量计算,并绘制了不同工况下的车道变换虚拟理想轨迹,用于分析各关键变量对路径规划的影响;其次,建立了线性离散的车辆动力学预测模型,综合分析了车辆模型的控制输入、状态变量以及道路结构参数等约束条件,构建了多约束模型预测控制(MMPC)系统用于车道变换路径跟踪,并基于Hildreth二次规划算法对其目标函数进行了求解,获得前轮转向角控制量,从而保证智能车辆在车道变换过程中的路径跟踪性能及操纵稳定性能;最后,利用MATLAB和Carsim软件对提出的多约束模型预测控制系统进行联合仿真,并构建单约束模型预测控制(SMPC)系统与其进行性能比较,分别对车道变换时间为3 s和6 s时的车道变换性能进行比较分析。结果表明:当车道变换时间为6 s时,2种控制系统都能较好地实现车道变换功能;当车道变换时间为3 s时,与SMPC控制系统相比较,MMPC控制系统能够在有效跟踪期望行驶路径的同时改善车辆的操纵稳定性,从而提高车辆在路径跟踪过程中的主动安全性能。 相似文献
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为了防止公交车辆在线路重叠运行区间产生公交串车,在站点附近形成交通瓶颈,提出一种采用车速诱导策略来调整公交运行状态的动态调度模型。采用车路协同环境下的公交运营调度方式,结合各线路独自运行时的乘客需求和车辆车头时距规律,在避免重叠区站点公交串车的前提下,实现了各线路车辆最大程度地维持各自独立运行时车头时距的优化目标。提出的车路协同环境下的车速诱导调度策略,在引导各线路公交车辆间隔均匀地进入重叠区间后,根据乘客实时交通需求和道路交通状况,实现对车辆的实时调控。开发了一种启发式算法对车辆进入重叠区间的时刻进行求解,采用基于遗传算法的仿真过程求解了重叠区站点之间车辆的最佳运行速度,实现了重叠区间车辆动态调度过程。以哈尔滨市运行区间重叠的3条公交线路为实际案例进行仿真分析,对3条线路共计47辆公交车在重叠区12个站点之间的运行状况进行了优化调度。结果表明:采用提出的启发式算法进行调度后,车辆可以完全均匀地进入重叠区。通过对比采用动态调度优化前后的车辆运行状态发现,车辆串车现象由优化前的单站最多发生6次下降为0次,最大程度地实现了避免公交串车的目标。此外,车速诱导策略不仅避免了不同线路车辆在重叠区站点的串车现象,而且可以调整各线路上相邻两车之间的车头时距偏差,线路1的车头时距最大偏差从55%下降到了30%,线路2的车头时距最大偏差从25%下降到了13%,线路3的车头时距最大偏差从23%下降到了18%。 相似文献
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This study was performed to clarify criteria for cavitation inception and the relationship between flow conditions and cavitation
flow patterns of diesel and biodiesel fuels. The goal was to analyze the effects of injection conditions and fuel properties
on cavitating flow and disintegration phenomena of flow after fuel injection. To accomplish this goal, it was utilized a test
nozzle with a cylindrical cross-sectional orifice and a flow visualization system composed of a fuel supply system and an
image acquisition system. In order to analyze the rate of flow and injection pressure of the fuel, a flow rate meter and pressure
gauge were installed at the entrance of the nozzle. A long distance microscope device equipped with a digital camera and a
high resolution ICCD camera were used to acquire flow images of diesel and biodiesel, respectively. The effects of nozzle
geometry on the cavitating flow were also investigated. Lastly, a detailed comparison of the nozzle cavitation characteristics
of both fuel types was conducted under a variety of fuel injection parameters. The results of this analysis revealed that
nozzle cavitation flow could be divided into four regimes: turbulent flow, beginning of cavitation, growth of cavitation,
and hydraulic flip. The velocity coefficient of diesel fuel was greatly altered following an increase in flow rate, although
for biodiesel, the variation of the velocity coefficient relative to the rate of flow was mostly constant. The cavitation
number decreased gradually with an increase in the Reynolds number and Weber number, and the discharge coefficient was nearly
equal to one, regardless of cavitation number. Lastly, it could not observe cavitation growth in the tapered nozzle despite
an increase in fuel injection pressure. 相似文献