基于ADAMS的前悬架仿真优化

悬架在整车中占据着举足轻重的地位,决定了车辆操纵稳定性及平顺性的好坏。为了使得初步设计的双横臂式独立悬架性能得到提升,论文采用多目标拓扑优化的方法对前悬架进行了优化。首先在ADAMS/CAR中建立了车辆前悬架模板子系统,仿真出车轮定位参数变化曲线。接着在ADAMS/Insight模块里,设计目标选为车轮定位参数,设计变量选为前悬架硬点坐标,根据敏感度大小,对前悬架硬点坐标进行了优化,曲线对比结果显示优化有效。     

基于Fluent的氢燃料电池空压机性能分析

文章针对某款氢燃料电池空压机建立二维模型,然后导入ICEMCFD软件进行网格划分,再利用Fluent 18.0软件,基于标准k-ε模型,采用SIMPLEC算法对其内部流场进行数值模拟,并分析了空压机内部流动现象和规律,最后与参考文献结果进行比较,验证了空压机仿真的准确性。     

NT2135柴油机曲柄活塞机构计算机辅助设计

文章介绍了在建立零件的三维模型基础上进行曲柄活塞机构的装配,并通过设置伺服驱动,实现了曲柄活塞机构的运动仿真;并对正常功率输出状态下曲柄活塞机构的运动进行了动力学分析,得出了活塞的速度和加速度分布。     

AMESim仿真软件在汽车机电技术中的应用

AMESim是一款专业的液压系统仿真软件,可进行液压系统、机电系统、伺服控制、热计算等多方面的仿真。文章介绍了AMESim软件基本仿真环境,及其在汽车机电、汽车发动机、自动驾驶等方面的应用。并对某型号的汽车发动机齿轮组进行了仿真模型的建立,通过转速输入控制,得到了齿轮组末端转速响应情况,可对发动机齿轮动力学进行预演仿真分析。将AMESim应用于汽车机电系统设计中,为其设计及优化提供仿真环境和设计参考。     

基于硬件在环的泊车控制器仿真测试

文章论述了一种基于硬件在环的泊车控制器测试系统的方案原理、构成以及测试过程。为了使用硬件在环测试系统验证泊车控制器功能,需要完成超声波探头激励测试、泊车控制器探测距离测试、泊车控制器功能测试。最终硬件在环的泊车控制器测试系统通过场景仿真软件对交通场景进行视觉模拟。同时,超声波板卡对模拟交通场景中目标信息进行超声波仿真模拟,并将以上信息提供给泊车控制器进行决策运算,完成泊车控制器功能的仿真测试。     

A microscopic simulation model for merging control on a dedicated-lane automated highway system

The automated highway systems (AHS) are not designed as stand-alone transportation facilities. Drivers will by necessity drive from their origins to the AHS entrance, and from the AHS exit to their final destinations. Therefore, the AHS will affect other transportation facilities, and should be integrated with all other facilities in the transportation system. Interfaces create much of the congestion for today’s transportation systems. Likewise, AHS interfaces may cause a similar problem, due to either AHS interactions with conventional systems or internal limitations from AHS merging capabilities. If these problems exist, either the AHS or the conventional road network cannot function properly. Consequently, the system as a whole may break down and the AHS could potentially become a detriment to the overall transportation system.Clearly, not enough is known about the automated merging process to determine what conditions would lead to congestion at interface points. The current macroscopic analysis techniques assume parameters that are not applicable to an AHS, and no detailed AHS merging models have been developed and validated. This paper addresses the interface problem between an AHS, and conventional roadway. Specifically, it presents a microscopic simulation model for one scenario of the automated merging maneuver. The results of the model show that for low flows and conventional highway speeds, an one-lane AHS merging section with a dedicated automated entrance ramp has many similar characteristics as a two-lane conventional freeway with or without fixed-time ramp metering. However, when the conventional freeway starts to “break down” near its capacity, the AHS continues to perform with little delay. The model also validates that the minimum ramp length requirements are a function of the merging vehicle’s speed, the mainline vehicles’ speed, and the acceleration and deceleration rates of the merging vehicle.     

A stochastic computational model for yellow time determination and its application

This paper proposes a stochastic model to determine the yellow time according to the occurring probability of Type‐I dilemma zone (P_DZ). Unlike the conventional methods generally based on the deterministic traffic flow theory, the proposed model fully accounts for the randomness of input variables such as approaching speed, deceleration rate, perception‐and‐reaction time, and distance to stop‐line at the yellow onset. A theoretical model is firstly established, and a computational program incorporating Monte Carlo Simulation is then developed to facilitate its general solution. These two alternative solution approaches to derive P_DZ and Y are proposed, depending upon whether D/V and (τ + V/2d) follow certain analytical distributions or not. In addition, field data at a typical high‐speed highway intersection are collected to validate the model. Based on the validated model, comprehensive sensitivity analysis is conducted to look into the entire picture of the relationship between P_DZ and the distributions as well as correlations of the input variables. To demonstrate the application of the proposed model, the required yellow times for various conditions are calculated based on the acceptable levels of P_DZ, and representative application tables for typical cases are finally provided. With the aid of the proposed methodology, traffic engineers are capable of designing yellow time in a more sophisticated manner. Copyright © 2014 John Wiley & Sons, Ltd.     

基于有限元法的某8×4重型载货车车架轻量化仿真分析

随着国家对安全、减重、节能和环保的重视,重卡轻量化的需求日益迫切.车架作为重卡最大的零部件,在满足强度的同时减轻重量成为轻量化的重点研究对象.文章基于有限元法对某8×4载货车车架进行轻量化仿真分析,对优化前后的车架各零部件的安全系数及总成模态值进行对比,确认方案的可行性.     

Fortran程序的可视化图形显示方法研究

以重载列车纵向动力学仿真系统为实例,研究Fortran程序进行可视化的图形界面显示方法.通过调用window API函数,构造基于window结构的联合Fortran应用程序,并以兼容位图形式实现多种图形绘制与数据显示.改善Fortran软件系统的可视化功能.为仿真系统进行性能参数分析提供有效的可视化平台.     

轿车白车身模态仿真计算与相关性分析

白车身模态分析是车身动态特性分析的基础。工程上常采用仿真计算和试验测试2种方法识别白车身模态参数。这2种方法相辅相成,互相促进,共同指导和改进设计。文章通过仿真建模计算了某车型白车身的模态频率,将计算结果和试验测试相比较,并采用相关性分析的方法验证了模型的可靠性,同时对比了不同焊点类型对于分析结果的影响。结果表明,建立的白车身仿真模型具有较高的精度,仿真计算所采用的模拟方法是合适的,为内部仿真建模指导规范的建立提供了参考。