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551.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(11):1401-1437
There are many situations where physical testing of a vehicle or vehicle controller is necessary, yet use of a full-size vehicle is not practical. Some situations include implementation testing of novel actuation strategies, analysing the behaviour of chassis feedback control under system faults, or near-unstable situations such as limit handling under driver-assist feedback control. Historically, many have advocated the use of scale vehicles as surrogates for larger vehicles. This article presents analysis and experimental testing that examines the fidelity of using scaled vehicles for vehicle chassis dynamics and control studies. In support of this effort, this work introduces an experimental system called the Pennsylvania State University Rolling Roadway Simulator (the PURRS). In the PURRS, a custom-built scale-sized vehicle is freely driven on a moving roadway surface. While others have used scale-vehicle rolling roadway simulators in the past, this work is the first to attempt to directly match the planar dynamic performance of the scale-sized vehicle to a specific full-sized vehicle by careful design of the scale vehicle. This article explains details of this effort including vehicle dynamic modelling, detailed measurement of model parameters, conditions for dynamic similitude, validation of the resulting experimental vehicle in the time, frequency, and dimensionless domains. The results of the dynamic comparisons between scale- and full-sized vehicles clearly illustrate operational regimes where agreement is quite good, and other regimes where agreement is quite poor. Both are useful to understand the applicability of scale-vehicle results to full-size vehicle analysis. 相似文献
552.
将列车的每节车厢简化为15自由度的动力系统,由拉格朗日方程导出其振动微分方程,将轨道梁简化为欧拉梁,基于能量法和车辆与轨道梁位移协调条件,建立了车辆和轨道梁耦合运动控制方程,研究了跨座式单轨交通轨道梁的动力特性。计算了列车以不同车速通过时轨道梁的动力响应,并比较了计算结果与实测结果。比较结果表明:理论计算结果与实测结果基本吻合,车速对轨道梁挠度的影响较小,但对加速度影响较大,加速度随车速增大而增大,在40~50 km.h-1处出现最大值,之后随车速增大反而减小;轮胎模型与轨道表面不平度功率谱密度函数对轨道梁横向响应计算结果影响较大,使计算误差增大。 相似文献
553.
554.
车辆重心高度对动力学性能的影响 总被引:1,自引:0,他引:1
随着我国铁路货物运输向重载化方向发展,车辆重心高度将产生大范围变化。我国铁路技术标准严格限制重车重心高度,当重心超过2000mm时,车辆要限速运行。在满载条件下,我国铁路现有的罐车实际重心高度普遍接近或高于2000mm。现以GQ70为例,采用SIMPACK仿真软件建立重车车辆模型,分析在不同运行工况下重心高度对车辆动力学性能的影响。计算结果表明,速度越高,车辆重心高度对动力学性能的影响越大,当车辆重心高度在1800mm到2600mm范围内变化时,对横向动力学性能及安全性影响较大,对垂向及轮轨动力学影响较小。 相似文献
555.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):819-834
The real-time simulation of vehicle trains requires an accurate and numerically feasible representation of the vehicle–trailer coupling. Although the equations of motion for the chassis instances can be reduced to systems of ordinary differential equations, additional constraints on the relative motion of vehicle and trailer are introduced when considering the hitch. In this article, we present a strategy for the simulation of vehicle–trailer combinations, where the algebraic constraints of the coupling are treated explicitly. Although this approach allows exact modeling of the respective joint geometry and realistic calculation of the coupling forces, a suitable numerical algorithm is required in order to solve the resulting differential-algebraic system of index 3 in real-time. The implementation in a commercial vehicle dynamics program is discussed and real-time simulation results are shown, which prove its feasibility for different coupling joints and demanding driving maneuvers. 相似文献
556.
KZ4A型机车转向架轴重增加后的设计改进 总被引:1,自引:1,他引:0
借鉴国内外200km/h等级机车轴重设计经验,通过对机车动力学性能的分析和对转向架主要部件的疲劳强度校核等,提出了KZ4A型机车转向架轴重增加后的设计改进措施。 相似文献
557.
文章主要介绍了一种比较常用的模态试验方法和某型电力机车车体钢结构模态试验。通过模态试验分析了机车结构模态特性对结构动态性能的影响。 相似文献
558.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):390-409
The Euler equation is a correct way for writing rotational moments of solids. But it is simple only if written in rotating frames. Applying it to railway wheelsets is difficult because it necessitates using the Euler angles, or Euler parameters, combined to rotation matrices or, numerically more stable, quaternions. Euler angles can be avoided in railway specific codes, by writing dynamical equations in track frames. However, academic literature [Landau LD, Lifshitz EM. Mechanics (Institute of Physical Problems, USSR Academy of Sciences, Moscow), Vol. 1, Course of theoretical physics. 21st English ed. Oxford (UK): Elsevier; 1960; Shabana AA, Zaazaa KE, Sugiyama H. Railroad vehicle dynamics. CRC Press; 2008.] does not provide simple solutions as to how properly writing equations of gyroscopic moments in no rotating frames. This paper describes how it is possible, owing to an approximation validated for railway applications, to avoid Euler angles and rotation matrices, while correctly taking into account gyroscopic effects. Using a most severe example, emphasising gyroscopic effects, it is demonstrated that a fast specific code using the approximation provides results equivalent to those of an multi body system generalised code with no approximation. 相似文献
559.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1190-1203
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. 相似文献
560.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):562-579
Small forced vibrations of an axle model of independent suspensions having four degrees of freedom are studied. The exact analytical solution of the generalised Lagrange equation enables one to produce 3D plots of the normalised amplitudes of forced vibrations versus frequency and excitation ratio or phase difference of the road inputs. The analysis of these plots exhibits some deficiency in damping of roll vibrations of conventional vehicle suspensions. The possibilities of improvement are discussed. 相似文献