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341.
B. Ozdalyan 《International Journal of Automotive Technology》2008,9(1):71-80
This paper describes the initial phase of work carried out as part of an on going study investigating the interaction between
the tyre, suspension system and an antilock braking system (ABS). The modelling, analysis simulations and integration of results
have been performed using an industry standard Multibody Systems Analysis (MBS) program. A quarter vehicle model has been
used together with an individual front suspension system represented by interconnected rigid bodies. The tyre model used can
be integrated into vehicle handling simulations but only the theory associated with the generation of longitudinal braking
forces is described here. An ABS model based on slip control has been used to formulate the braking forces described in this
paper. The simulations, which have been performed braking on wet and dry road surfaces, compare the performance of two different
tyres. 相似文献
342.
通过对列车行车组织特点及运行调整策略的研究,采用自适应动态规划体系中的双重启发式动态规划算法,建立了列车运行调整模型.双重启发式动态规划算法适合处理具有实时性、约束性、非线性、随机性等特点的列车运行调整复杂动态系统的优化控制问题,通过仿真验证,该算法求解速度快、精度高,对列车晚点的调整起到了良好的控制作用.为列车运行调整的深入研究提供了一定的参考价值. 相似文献
343.
The paper presents a comprehensive validation procedure for the passenger traffic model for Copenhagen based on external data
from the Danish national travel survey and traffic counts. The model was validated for the years 2000–2004, with 2004 being
of particular interest because the Copenhagen Metro became operational in autumn 2002. We observed that forecasts from the
demand sub-models agree well with the data from the 2000 national travel survey, with the mode choice forecasts in particular
being a good match with the observed modal split. The results of the 2000 car assignment model matched the observed traffic
better than those of the transit assignment model. With respect to the metro forecasts, the model over-predicts metro passenger
flows by 10–50%. The wide range of findings from the project resulted in two actions. First, a project was started in January
2005 to upgrade the model’s base trip matrices. Second, a dialog between researchers and the Ministry of Transport has been
initiated to discuss the need to upgrade the Copenhagen model, e.g. a switching to an activity-based paradigm and improving
assignment procedures. 相似文献
344.
Giorgio Previati Massimiliano Gobbi Giampiero Mastinu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(1):37-60
The modelling problems related to the simulation of the dynamics of farm tractors are dealt with. The aim is to develop reliable mathematical models to speed-up the research and development activities in which farm tractors and their sub-systems (driveline, steering and suspension system, etc.) are to be conceived and designed. Two models of farm tractors have been developed. The first model is based on a proprietary software, able to quickly simulate the motion of a vehicle on smooth or rough soil. The second model has been developed by the commercial software ADAMS/Car®, which allows to model complicated transmission and suspension systems. In both of the two models, the tyres, the transmission system, the suspension system, the steering system, the engine and the body inertia are carefully described mathematically. Both of the two models are defined in a parametric way. Particular attention has been devoted to the measurements of the tyre characteristic and of the inertia parameters of the farm tractor body. For the measurement of tyre characteristics, a new instrumented wheel hub has been used. The accurate measurement of both the tyre characteristic and body inertia tensor has allowed a good agreement between measured and computed time histories referring to a number of validation manoeuvres performed either on-road or off-road. The derived farm tractor models could simulate the working conditions of a generic farm tractor while hauling a plough or while running at a relatively high speed on a rough soil or while steering on a sloped, soft surface. 相似文献
345.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):653-669
This paper addresses modelling, longitudinal control design and implementation for heavy-duty vehicles (HDVs). The challenging problems here are: (a) an HDV is mass dominant with low power to mass ratio; (b) They possess large actuator delay and actuator saturation. To reduce model mismatch, it is necessary to obtain a nonlinear model which is as simple as the control design method can handle and as complicated as necessary to capture the intrinsic vehicle dynamics. A second order nonlinear vehicle body dynamical model is adopted, which is feedback linearizable. Beside the vehicle dynamics, other main dynamical components along the power-train and drive-train are also modelled, which include turbocharged diesel engine, torque converter, transmission, transmission retarder, pneumatic brake and tyre. The braking system is the most challenging part for control design, which contains three parts: Jake (engine compression) brake, air brake and transmission retarder. The modelling for each is provided. The use of engine braking effect is new complementary to Jake (compression) brake for longitudinal control, which is united with Jake brake in modelling. The control structure can be divided into upper level and lower level. Upper level control uses sliding mode control to generate the desired torque from the desired vehicle acceleration. Lower level control is divided into two branches: (a) engine control: from positive desired torque to desired fuel rate (engine control) using a static engine mapping which basically captures the intrinsic dynamic performance of the turbo-charged diesel engine; (b) brake control: from desired negative torque to generate Jake brake cylinder number to be activated and ON/OFF time periods, applied pneumatic brake pressure and applied voltage of transmission retarder. Test results are also reported. 相似文献
346.
347.
陈建平 《上海交通大学学报(英文版)》1997,(1)
PSPICEMODELLINGOFLEDChenJianping(陈建平)(NationalKeyLab.onLocalFiber-OpticCommunicationNetworksandAdvancedOpticalCommunicationSy... 相似文献
348.
柔性神经网络及其在开关磁阻电机建模与仿真中的应用 总被引:3,自引:1,他引:3
作为一种新型的神经网络,创建了具有高度柔性特性的网络结构,给出了柔性神经网络(FNN)的基本原理,并将其应用于开关磁阻电机(SRM)的建模与仿真,展示了SRM新型建模方法的主要优点。FNN在实现系统功能的同时,需要较少的神经元和迭代循环,大大降低了网络的复杂性,加速了网络的学习与实时计算速度。 相似文献
349.
This paper presents a research on traffic modelling developed for assessing traffic and energy performance of electric systems installed along roads for dynamic charging-while-driving (CWD) of fully electric vehicles (FEVs).The logic adopted by the developed traffic model is derived from a particular simulation scenario of electric charging: a freight distribution service operated using medium-sized vans. In this case, the CWD service is used to recover the state of charge of the FEV batteries to shortly start with further activities after arrival at the depot.The CWD system is assumed to be implemented in a multilane ring road with several intermediate on-ramp entrances, where the slowest lane is reserved for the dynamic charging of authorized electric vehicles. A specific traffic model is developed and implemented based on a mesoscopic approach, where energy requirements and charging opportunities affect driving and traffic behaviours. Overtaking manoeuvres as well as new entries in the CWD lane of vehicles that need to charge are modelled according to a cooperative driving system, which manages adequate time gaps between consecutive vehicles. Finally, a speed control strategy is simulated at a defined node to create an empty time-space slot in the CWD lane, by delaying the arriving vehicles. This simulated control, implemented to allow maintenance operations for CWD that may require clearing a charging zone for a short time slot, could also be applied to facilitate on-ramp merging manoeuvres. 相似文献
350.
带软时间窗的混合车队车辆路线问题的模型和算法研究 总被引:21,自引:3,他引:21
将典型的车辆路线问题扩展为综合考虑了客户具有间窗约束和中央仓库拥有多种类型配送车辆的情况。在构造了问题的数学模型后,着重阐述了求解本问题的TS算法设计过程。最后结合适应性记忆过程给出了TS算法的伪代码描述和一个算法。 相似文献