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531.
K. -H. Moon S. -H. Lee S. Chang J. -K. Mok T. -W. Park 《International Journal of Automotive Technology》2009,10(4):441-449
Many methods we have been developed to control the rear wheels of a vehicle, but most of them are designed for automobiles
with four wheels. The AWS (all wheel steering) control method for articulated vehicles is currently applied only to Phileas
vehicles developed by APTS, but the control algorithm for this system has yet to be reported. In the present paper, a new
algorithm is proposed after the AWS ECU (electronic control unit) of the Phileas vehicle was tested and analyzed in order
to understand the existing steering algorithm. The new algorithm considers the vehicle geometry, stability of handling, and
safety, and can be easily applied to multi-axle vehicles. In order to verify the AWS algorithm, the trajectory and steering
angles of each algorithm were compared using the commercial software ADAMS. Turning radius, swing-out, and swept path width
were also investigated to determine the turning performance of the proposed algorithm. 相似文献
532.
C. -L. Wang C. -L. Yin T. Zhang L. Zhu 《International Journal of Automotive Technology》2009,10(5):589-596
The powertrain of an ultra-capacitor-based parallel hybrid electric vehicle (HEV) was developed. Innovations, such as the
engine management system, floating ISG (Integrated Starter and Generator), electronic-controlled double-clutch system and
dual-driven air conditioning system were realized. Hybrid control strategies to improve the fuel economy and reduce emissions
were analyzed briefly. In order to ensure the vehicle emission performance, the engine management system calibration was performed.
The vehicle emission test was also conducted, showing that the vehicle emission satisfied the EURO III standard and has great
potential for improvement. The hybrid start test was introduced in detail. We realized the hybrid function and start parameter
optimization of the engine and ISG. 相似文献
533.
大跨悬索桥箱形钢桁架梁的综合疲劳评定方法研究 总被引:1,自引:1,他引:0
根据大跨桥梁铜箱梁各类构件的受力特点建立了确定钢箱梁关键疲劳构件的评价模型,提出了基于结构有限元分析、应变监测信息、构件分级系统和桥梁结构人工检测等多方面信息综合评定关键疲劳构件的方法。以某大跨悬索桥钢箱梁结构为例,结合结构有限元数值计算和结构健康监测系统确定的关键钢箱梁截面,针对关键截面上的主要构件分布,利用应变传感器输出信息、结构有限元分析得到的应力分布信息、人工检测信息和桥梁主要构件的危险等级和易损等级信息,结合层次分析法和模糊综合评判理论确定了影响钢桥构件疲劳评定的各因素的权重,用综合隶属度评分法进行关键疲劳构件的等级评定。 相似文献
534.
The vibrational characteristics of automotives during idling were studied experimentally by considering the axial forces of
the drive shaft and the spider positions in a constant-velocity joint. The generated forces, such as PF (plunging force) and
GAF (generated axial force) in the assembly of the drive-shaft module, were measured directly by an experimental apparatus.
Measurements of the GAF and PF did not show the same trends as the joint angles. They depended instead on the types of CV
joints. In addition, the relationship between the offset values of the shaft and the spider positions in the tulip of the
constant-velocity joint were studied. As a result, the idle vibration characteristics were affected by the variation of the
spider positions and the vibrational characteristics in the axial direction of the shaft, including the amplitude and the
harmonic periods. 相似文献
535.
H. Liu G.N Liu K J Huo T Liu X H Zhang K Liu K Tao Y. J. Liu . Mechanical Engineering School Xi''''an Jiaotong University Xi''''an China . Strength Centre Zhengzhou Research Institute of Mechanical Engineering Zhengzhou China . Fo 《上海交通大学学报(英文版)》2000,(1)
IntroductionThefiwtee1emenmethod(FEM)playsanextrmelyimPortantroleintheanalysesofengineeringproblems.ForalongtimethismethodhasmainlybeenaPPliedinthelinearfieldandshownitsgreatpower.HoweveealOtofnonlinearengineeringPrOblemsWhichcanneitherbesimPlyreducedtolinearonesnorrCPresentedbylinearlyanalogywhichshallchnsethePfacticalconditionsrelativelymuch,havechallengedfiniteelementmethod(FEM).RecentymuchProgresshasbeenmadebothinthemathematicalandmechanicaltheoryandthecomPulertechnologysothatevent… 相似文献
536.
Piet M. T. Broersen 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1974,3(2):109-121
The so-called critical speed of a linearized railway vehicle is shown to be no useful measure for the stability of the system in practice. The important interaction between vehicle and track can be taken into account by the riding quality for a certain vehicle on every particular piece of track. The riding quality is determined by the accelerations transmitted to the payload, weighted according to comfort standards, and the relative displacements between wheel and rail. From the riding quality demands both for vehicle design and for maintenance of the track can be derived. 相似文献
537.
Adaptive Control of 4WS System by Using Neural Network 总被引:3,自引:0,他引:3
T. Shiotsuka A. Nagamatsu K. Yoshida 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1993,22(5):411-424
An adaptive control system of the model following type is proposed for drive motion control of a four wheel steering (4WS) car with using neural network (NN) which has mastered nonlinear friction force between tire and road surface. A model of one rigid body is adopted which represents appropriately two kinds of car motion caused by steering action, namely the lateral displacement and the yawing rotation, and an equation of motion is described in a simplified form to make a system equation for motion control possible. Nonlinear relation between the cornering force of tire and the slip angle is obtained by numerical analysis with the tire model proposed by E. Fiala, taking friction coefficient and car speed as the parameters. The result is used as the teaching signal for NN. Three NN are used in the control system composed of both the feed-forward and the feedback circuits in order to realize adaptive control. Validity and usefulness of the proposed adaptive control system with NN are verified by three kinds of computer simulation. 相似文献
538.
Modal split models tried for Indian cities have not gone in depth in studying the impact of the attitude of users towards various travel attributes. The main difficulty with this has been non-availability of data. The study presented here tried two methodologies, attitude measurement and trade-off game approach, using data collected through household surveys conducted for the purpose on limited stratified samples in some locations in Madras. The results indicate how commuters value time and comfort factors more than the cost, given a choice. Due to prevailing economic conditions, cost plays a vital role, but analysis shows that users are prepared to incur additional cost, if they are assured of quicker and more comfortable services. Relative quantification between the influence of different attributes is also possible. 相似文献
539.
An evaluation of web site services in liner shipping in Taiwan 总被引:2,自引:0,他引:2
This paper empirically evaluates web site services in the liner shipping industry based on the service requirements of the user firms, i.e., shippers. The results suggest that shippers perceive tracing to be the most important service attribute of a web site, followed by customs response, vessel schedules, and electronic document service. Based on the concept of market segmentation, we employed cluster analysis to classify users (shippers) of web site services provided by liner shipping companies into four segments, namely support and performance services oriented firms, equipment information oriented firms, performance information oriented firms, and transaction services oriented firms. Theoretical and practical implications of the research findings are discussed. 相似文献
540.