基于车辆位置与速度特征的驾驶行为模式分类方法

精细车辆轨迹中包含连续的时间戳、位置,以及速度等信息。通过对车辆轨迹数据进行量化表达与挖掘分析,可以实现对车辆行为模式的分类。现有研究大多关注对位置的聚类,很少对车速、加速度等特征进行研究分析,而车速等是反映驾驶行为模式的重要特征。为了将轨迹多维信息纳入分析框架,研究了基于位置与速度特征的车辆轨迹行为模式分类方法。为克服现有行为模式分类方法的维度单一性,运用豪斯多夫轨迹距离算法计算出位置和速度特征的综合距离矩阵,针对豪斯多夫距离算法鲁棒性差的缺点,采用单向豪斯多夫距离90%分位值对算法进行了改进,降低噪声影响。同时,引入了车辆位置和速度来进一步提高分类的准确性,运用多次分层聚类算法依次对位置与速度轨迹图进行分类,得到车辆位置和速度上的行为模式。以HighD数据集为样本,提取了三车道上的行车轨迹,验证了基于速度与位置特征的车辆行为模式分类方法。结果表明：(1)本方法可以得到位置和速度的综合行为模式,聚类平均准确率达到94.8%,优于DBTCAN准确率89.3%和t-Cluster准确率86.4%;(2)基于换道模式轨迹偏移率曲线的分析,得到了4种互异的典型车辆换道模式。该方法可利用多维轨...     

车辆荷载作用下脱空地基上CRCP板的挠度研究

基于连续配筋混凝土路面板挠度等效原则,转换了板中车辆集中荷载时的荷载作用模式。运用弹性薄板理论,推导出车辆集中荷载作用于板中时脱空的连续配筋混凝土路面板的挠度计算公式,同时运用有限元挠度计算结果对理论公式挠度计算结果进行了对比验证,两者基本吻合。     

军警ETC车道布局对收费站服务水平的影响研究

为有效利用车道资源,提高ETC车辆的通过率,部分省份将军警车道升级改造成前置式军警ETC车道或后置式军警ETC车道,但不同军警ETC车道布局对收费站服务水平的影响程度尚不明确.文中以广韶高速太和收费站为研究对象,运用Vissim交通仿真软件进行仿真建模,对比分析不同军警ETC车道布局下ETC车辆、军警车辆、人工半自动收费(MTC)车辆等车种的平均行程时间、平均延误时间、平均排队长度等评价指标.仿真结果表明:经升级改造后,ETC车辆的各项评价指标改善显著,军警车辆受到较小的影响,MTC车辆未受到影响;在低峰、平峰时段中,2种军警ETC车道布局模式下收费站的各项评价指标差别较小,在高峰时段中,与前置式布局模式相比,后置式布局模式下ETC车辆和军警车辆的平均行程时间均提高了9.6%、平均延误时间均降低了12.8%、平均排队长度均减少了26.7%.因此,建议交通流量较大的大型收费站采用后置式军警ETC车道布局模式,交通流量较小的小型收费站可采用前置式或后置式军警ETC车道布局模式.      

基于共享模式的网联自动驾驶车辆路径规划研究

物联网、大数据、移动互联等新一代信息技术在自动驾驶方面的运用,为交通信息化和智能化带来了新的发展契机.作为集约型的城市交通发展模式,共享出行已成为学界关注的热点问题.在共享模式和自动驾驶协同发展的时代背景下,提出了随机需求下考虑用户等待时间的网联自动驾驶共享车辆路径规划模型.为验证模型的有效性和鲁棒性,在虚拟网格式路网中设计应用算例,基于优化工具Gurobi对模型进行求解,确定最优的网联自动驾驶车辆规模及最优车辆服务路径,并与个体最优情况下的出行成本及能耗进行对比.研究结果表明,共享模式能大幅度减少车辆数,降低系统总体成本及能耗,在提高车辆使用率和可持续性方面效果显著.     

动态交通分配中一种多模式动态决定式点排队模型及其特性分析

提出了一个可应用于动态交通分配中的多模式决定式点排队模型。模型中不同的交通模式(如小汽车、卡车和公交车等)由于车辆特性以及长度的差异在路网中将分别具有不同的行驶特性。为了能够反映不同模式车辆在路段上的相互作用,将单模式点排队模型扩展为多模式点排队模式。并对这个模型的相关特性进行了研究,如:反映不同模式车辆在路段上的速度收敛特性,在路段上每一模式车辆的先入先出特性(FIFO)以及路段上不同模式车辆的因果特性。     

基于信息融合的车辆险态运行模式评价研究

提出了一种车辆运行状态识别体系.鉴于车辆行驶环境的复杂性,多作业工况条件的影响以及车辆行驶行为表现特征的多元性,采用BP神经网络技术与Dempster-Shafer证据推理技术相结合的信息模式分类及融合判断的解决方案.为验证所提出的方案,建立车载摄像机视频实时检测系统,以车道偏离信息和跟驰车间距信息作为车辆行驶的表征参量,实现车辆险态行驶特征表现的检测和评价.研究结果表明,模式分类和多源信息融合决策技术的综合运用提高了车辆危险行驶姿态表征信息甄别的自适应性和智能化水平.      

汽车托运平板车辆的模拟试验方法研究EI北大核心CSCD

为了在整车开发的前期阶段及早预测车辆在运输过程中的疲劳失效问题,搭建了汽车托运平板车辆模拟试验台架,制定了试验方法并进行试验。将耐久试验车辆零件的失效模式与实际汽车托运平板车辆运输过程中车辆零件的失效模式进行对比,验证了汽车托运平板车辆模拟试验方法的有效性。     

基于大数据的电动汽车分时租赁服务模式改进

提出了关于电动汽车分时租赁服务模式的改进,基于大数据分析了电动汽车分时租赁服务模式的现状和特点,提出了目前分时租赁中典型的问题并运用大数据理论来解决。重点解决车辆布局及其服务标准化,以及运用大数据降低管理风险,将大数据融入到分时租赁服务模式的管理中,促进分时租赁服务模式的创新发展。     

军用车辆动态信息的获取与运用评价模型

在军用车辆管理信息系统中，建立合理的车辆运用模型是获取车辆动态信息的关键性工作，章给出了车辆运行中动态时间(函数)的概念以及获取方法；描述了车辆运用动态向量的诸要素以及它们之间的关系；建立了基于动态时间的车辆运用向量各状态时的计算模型；最后利用车辆动态信息构成的诸要素，建立一些车辆运用评价模型。     

汽车托运平板车辆的模拟试验方法研究

为了在整车开发的前期阶段及早预测车辆在运输过程中的疲劳失效问题,搭建了汽车托运平板车辆模拟试验台架,制定了试验方法并进行试验。将耐久试验车辆零件的失效模式与实际汽车托运平板车辆运输过程中车辆零件的失效模式进行对比,验证了汽车托运平板车辆模拟试验方法的有效性。     

A method to determine the two-point contact zone and transfer of wheel–rail forces in a turnout

A practical method to determine the zone of two contact points and the transfer of wheel–rail forces between two rails in a turnout is presented in this paper. The method is based on a wheel–rail elastic penetration assumption and used to study a turnout system for a 200 km/h high-speed railway in China. Rail profiles in a number of key sections in the turnout are identified first, and profiles in other sections are then obtained by interpolation between key sections. The track is modelled as flexible with rails and sleepers represented by beams and the interaction between the vehicle and turnout is simulated for cases of the vehicle passing the turnout. Results are mainly presented for two-point contact positions and the characteristics of the wheel–rail forces transference. It is found that the heights of the switch and crossing rail top have significant effects on the wheel–rail contact forces. Finally, the optimised top height for the crossing rails is proposed to reduce the system dynamic force in the turnout system.     

Dynamic model for ride comfort evaluations of the rubber-tired light rail vehicle

The dynamic model was developed to evaluate vibration accelerations and ride comforts during the running of the Korean-standardised rubber-tired light rail vehicle. Ride comfort indexes were analysed and tested in accordance with UIC 513R by using the dynamic model and the actual vehicle in the test track. Based on the comparisons between analysis results and test results, the validity of the developed dynamic model was evaluated. It was verified whether or not the developed Korean-standardised rubber-tired light rail vehicle met the specified target specification on ride comfort. In addition, the influence of the wearing of guide wheels on ride comfort was estimated.     

市域快线长大区间故障救援与配线设置探讨

市域快线站间距通常远大于常规地铁线路,在市域快线长大区间中采用常规地铁的故障救援模式及救援速度可能导致救援时间过长。为了提高市域快线长大区间故障救援效率,以广州市规划的首条160 km时速市域快线为例,在分析常规地铁故障救援流程、救援速度和救援时间的基础上,对市域快线故障救援速度进行探讨,进而设计了长大区间设置渡线和设置停车线2类方案,与无配线方案在救援时间、后续堵塞列车疏散效率等关键指标上进行综合比选,最后提出不同的区间停车线形式并进行了对比分析。研究表明:在长大区间设置停车线的方案救援功能较好,建议在工程条件允许时优先采用;不同的区间停车线形式各有优劣,应根据实际情况综合考虑运营功能和工程规模后选择。     

An inverse design method for rail grinding profiles

Inspired by the optimisation design method for restoration of worn wheel profiles, an inverse design method based on optimal rail grinding profiles is presented in this paper. To improve grinding quality, vehicle dynamic performance is chosen as the main criteria and rolling radii difference function is selected as the key factor (also main target function) determining dynamic performance. Grinding material to be removed is chosen as the auxiliary target aimed at extending rail service life. Besides that, wheel–rail contact distribution is also taken into consideration as an auxiliary target preventing stress concentration and fatigue growth. By introducing certain presuppositions, all the design targets will form an inverse design problem. This problem can be solved using hybrid discrete numerical methods. Considering different grinding requirements, two examples of grinding profile design for straight and curved track will be discussed. Results show that the presented method is efficient and effective. Practical implementation has been carried out at several grinding sites in China.     

Influence of wheel–rail contact modelling on vehicle dynamic simulation

This paper presents a comparison of four models of rolling contact used for online contact force evaluation in rail vehicle dynamics. Until now only a few wheel–rail contact models have been used for online simulation in multibody software (MBS). Many more models exist and their behaviour has been studied offline, but a comparative study of the mutual influence between the calculation of the creep forces and the simulated vehicle dynamics seems to be missing. Such a comparison would help researchers with the assessment of accuracy and calculation time. The contact methods investigated in this paper are FASTSIM, Linder, Kik–Piotrowski and Stripes. They are compared through a coupling between an MBS for the vehicle simulation and Matlab for the contact models. This way the influence of the creep force calculation on the vehicle simulation is investigated. More specifically this study focuses on the influence of the contact model on the simulation of the hunting motion and on the curving behaviour.     

A comparative study on fault detection methods of rail vehicle suspension systems based on acceleration measurements

Reliability of the railway vehicle suspension system is of critical importance to the safety of the vehicle. On-line health condition monitoring for the suspension system of rail vehicles offers a number of benefits such as preventing further deterioration of vehicle performance, enhancing vehicle safety, increasing operational reliability and availability, and reducing maintenance costs. It is desirable to timely detect the fault and monitor the performance degradation of vehicle suspension systems. In this paper, a comparative study on fault detection methods of urban rail vehicle suspension systems is considered. A novel sensor configuration is proposed where the underlying vehicle system is equipped with only acceleration sensors in the four corners of the carbody, the leading and trailing bogie, respectively. A mathematical model is developed for the considered vehicle suspension system. Both model-based and data-driven approaches are studied for the suspension fault detection problem. The robust observer, the Kalman filter combined with the generalised likelihood ratio test method, the dynamical principle components analysis and the canonical variate analysis approaches are applied to the fault detection problem. The simulation is carried out by means of the professional multi-body simulation tool, SIMPACK. In addition, the advantages and disadvantages of these methods are compared. The simulation results show that the data-driven methods outperform the model-based methods.     

An analytical mathematical method for calculation of the dynamic wheel–rail impact force caused by wheel flat

The simplified method to determine a vertical impact force of wheel with flat and rail interaction is presented in this article. The presented simplified method can be used to identify maximum contact force and its distribution in the contact length between the damaged wheel and the rail. The vertical impact force depends on geometrical parameters of the rail and wheel with flat, speed of vehicle and the angle of deviation of rail. This article demonstrates the influence of wheel with flat geometrical parameters, speed of vehicle to maximum contact force and its distribution in the contact zone. The obtained values of the simplified method for determination of a vertical contact force are compared with the results obtained from field measurements.     

重庆轻轨大溪沟车站桥动力性能分析

采用空间离散模型，计算重庆跨座式单轨交通线路大溪沟车站桥的结构自振特性。采用车桥作用理论的荷载列方法，计算15种工况下轻轨车辆经过时的结构振动。结果表明：该车站桥的结构设计较合理，结构具有足够的刚度，整体动力性能较好；桥上各处的振动均满足人体舒适度要求。     

Improvement of vehicle–turnout interaction by optimising the shape of crossing nose

Proper rail geometry in the crossing part is essential for reducing damage on the nose rail. To improve the dynamic behaviour of turnout crossings, a numerical optimisation approach to minimise rolling contact fatigue (RCF) damage and wear in the crossing panel by varying the nose rail shape is presented in the paper. The rail geometry is parameterised by defining several control cross-sections along the crossing. The dynamic vehicle–turnout interaction as a function of crossing geometry is analysed using the VI-Rail package. In formulation of the optimisation problem a combined weighted objective function is used consisting of the normal contact pressure and the energy dissipation along the crossing responsible for RCF and wear, respectively. The multi-objective optimisation problem is solved by adapting the multipoint approximation method and a number of compromised solutions have been found for various sets of weight coefficients. Dynamic behaviour of the crossing has been significantly improved after optimisations. Comparing with the reference design, the heights of the nose rail are notably increased in the beginning of the crossing; the nominal thicknesses of the nose rail are also changed. All the optimum designs work well under different track conditions.