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A. D. Dorey M. C. Good P. N. Joubert 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1980,9(1):19-44
A variable characteristic car (VCC) has been developed at Melbourne University for driverlvehicle handling research. The vehicle is unusual in that it has facilities for varying both its fixed control and free control dynamic characteristics over wide ranges. In this paper the servo systems used to effect these changes are described. The calibration methods used to relate the vehicle response characteristics to the variable servo settings are detailed. Sample calibration results are given for the fixed control parameters steering ratio, yaw response time and stability factor. Calibration of the free control parameters is also described and results are given for the steering torque gradient, and the time-to-peak and percentage overshoot of the steering wheel motion in response to a step input of torque. 相似文献
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对结构工程师来说,设计优化正变得日益重要。该文描述了一种结合机构法和遗传算法进行整体化设计优化的方法。前种方法是当前英国交通部采用的一种主要的计算拱的工具;后者是强有力的数值函数优化方法。文中显示了英国肯特Teston桥和一系列其它样本设计优化的试算结果及相关的算法有效性数据。建议本方法为涉及现存桥梁的评估、维护和修理及新拱桥设计的结构工程师的设计辅助工具。 相似文献
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穆怀旗 《内蒙古公路与运输》2006,(3):54-56
就美国交通的基本情况、发展模式、交通工具的选择和新技术的应用、智能交通系统及私有化和外包等诸多方面进行了深入的探讨,对美国交通的发展趋势做出了详尽而有理有据的预测,这样的综合介绍无疑会使我国的交通规划与发展颇受裨益。 相似文献
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C. Vera B. Suarez J. Paulin P. Rodrí guez 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2006,44(8):595-614
Overhead rigid conductor arrangements for current collection for railway traction have some advantages compared to other, more conventional, energy supply systems. They are simple, robust and easily maintained, not to mention their flexibility as to the required height for installation, which makes them particularly suitable for use in subway infrastructures. Nevertheless, due to the increasing speeds of new vehicles running on modern subway lines, a more efficient design is required for this kind of system.
In this paper, the authors present a dynamic analysis of overhead conductor rail systems focused on the design of a new conductor profile with a dynamic behaviour superior to that of the system currently in use. This means that either an increase in running speed can be attained, which at present does not exceed 110 km/h, or an increase in the distance between the rigid catenary supports with the ensuing saving in installation costs.
This study has been carried out using simulation techniques. The ANSYS programme has been used for the finite element modelling and the SIMPACK programme for the elastic multibody systems analysis. 相似文献
In this paper, the authors present a dynamic analysis of overhead conductor rail systems focused on the design of a new conductor profile with a dynamic behaviour superior to that of the system currently in use. This means that either an increase in running speed can be attained, which at present does not exceed 110 km/h, or an increase in the distance between the rigid catenary supports with the ensuing saving in installation costs.
This study has been carried out using simulation techniques. The ANSYS programme has been used for the finite element modelling and the SIMPACK programme for the elastic multibody systems analysis. 相似文献
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A.G. Thompson C.E.M. Pearce 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1998,30(1):17-35
An optimal preview type active suspension with feedback control based on easily measured relative displacements, velocities and accelerations is proposed. Measurements relative to the road, except by the preview sensor, are not required and the front and rear spring rates are quite arbitrary. Also, state estimators or observers are unnecessary and as a practical alternative the body accelerometers may be replaced by load cells. The effects of preview on the performance, for a theoretical step type road input and an analogous random road input, are described. The definition of the optimum preview function, and its consequent effects on performance, receives attention and an example is given. 相似文献