混凝土泵车底盘的专用化设计要素探讨

根据混凝土泵车的作业特点,介绍了混凝土泵车底盘与通用重卡底盘设计的区别,并对混凝土泵车底盘总体布置、动力系统、传动系统、行驶系统、电器系统的专用化设计进行了介绍,便于设计人员掌握混凝土泵车底盘的设计要素。     

Impact of container chassis management practices in the United States on terminal operational efficiency: An operations and mitigation policy analysis

Existing policies designed to mitigate the environmental and social impacts of truck queuing at maritime terminals often focus on congestion problems outside of the terminal gate, targeting a reduction in the waiting and turn time of trucks as the measure of success. This paper evaluates the impact that intra-terminal truck and equipment movements have on the terminal’s overall performance and the implications that these movements have on the effectiveness of current mitigation policies. Through a simulation of terminal processes occurring at Southern California ports it is shown that measures driving reductions in truck turn times impose greater operational loads on terminal equipment, essentially transferring savings in truck turn time rather than eliminating it in terms of the overall system. Consequently, the paper finds that total truck and cargo handling equipment movement and operational time constitutes a more accurate measure of the effectiveness of policies seeking to mitigate the impacts of truck operations at marine terminals.     

大型油压机的三种新型同步控制方式的对比浅析

本文介绍和分析了液压机同步控制的工作原理,对比了三种自动同步控制系统的结构和控制策略,并在此基础上,分析和研究了它们在大型油压机中应用效果的优劣。     

基于组态软件的汽车空调整车环境模拟试验室的研制

介绍汽车空调整车环境模拟试验室的原理、结构的研制及应用。     

基于ANSYS Workbench清障车底盘有限元分析

国内清障车基本是由载货汽车的二类底盘改装而成的,其底盘结构不能完全适应清障车作业,底盘性能未能充分利用。基于ANSYS Workbench软件对清障车底盘进行了有限元计算,分析了制约清障车作业能力的原因,并进行了结构改进。     

Influence of unsteady aerodynamics on driving dynamics of passenger cars

Recent approaches towards numerical investigations with computational fluid dynamics methods on unsteady aerodynamic loads of passenger cars identified major differences compared with steady-state aerodynamic excitations. Furthermore, innovative vehicle concepts such as electric-vehicles or hybrid drives further challenge the basic layout of passenger cars. Therefore, the relevance of unsteady aerodynamic loads on cross-wind stability of changing basic vehicle architectures should be analysed. In order to assure and improve handling and ride characteristics at high velocity of the actual range of vehicle layouts, the influence of unsteady excitations on the vehicle response was investigated. For this purpose, a simulation of the vehicle dynamics through multi-body simulation was used. The impact of certain unsteady aerodynamic load characteristics on the vehicle response was quantified and key factors were identified. Through a series of driving simulator tests, the identified differences in the vehicle response were evaluated regarding their significance on the subjective driver perception of cross-wind stability. Relevant criteria for the subjective driver assessment of the vehicle response were identified. As a consequence, a design method for the basic layout of passenger cars and chassis towards unsteady aerodynamic excitations was defined.     

Coordinated control strategies for active steering,differential braking and active suspension for vehicle stability,handling and safety improvement

ABSTRACT

In this paper, a coordinated control strategy is proposed to provide an effective improvement in handling stability of the vehicle, safety, and comfortable ride for passengers. This control strategy is based on the coordination among active steering, differential braking, and active suspension systems. Two families of controllers are used for this purpose, which are the high order sliding mode and the backstepping controllers. The control strategy was tested on a full nonlinear vehicle model in the environment of MATLAB/Simulink. Rollover avoidance and yaw stability control constraints have been considered. The control system mainly focuses on yaw stability control. When rollover risk is detected, the proposed strategy controls the roll dynamics to decrease rollover propensity. Simulation results for two different critical driving scenarios, the first one is a double lane change and the other one is a J-turn manoeuvre, show the effectiveness of the coordination strategy in stabilising the vehicle, enhancing handling and reducing rollover propensity.     

底盘测功机机械惯量电模拟方法的研究和实现

为开发汽车排气污染物简易瞬态工况法测试系统，研究了底盘测功机机械惯量电模拟的相关理论和方法。通过汽车在底盘测功机上运行状态的动力学分析，基于汽车驱动轮转动动态特性相同的原理，建立了汽车底盘测功机机械惯量的电模拟模型。分析了简易瞬态测试工况控制要求和风冷电涡流测功器的性能特点，构建了VMAS测试工况控制系统，应用预测控制和解耦控制理论和技术，设计了底盘测功机机械惯量电模拟控制方案，开发了基于DMC，具有模型增益自校正和解耦功能的VMAS测试扭矩控制器和简易瞬态工况控制试验系统。运行试验结果表明，该系统可以较好地模拟汽车加速运动惯量。     

汽车底盘线控技术的应用及发展趋势

现代汽车控制技术正朝着线控的方向发展,线控系统将取代以液压、气压和机械为主的传统控制系统。本文介绍了汽车底盘线控技术的研究现状,着重介绍了线控制动和线控转向系统的结构组成和性能特点,并提出线控技术的发展趋势。     

大规模定制的汽车底盘产品族建模方法研究

在建立汽车底盘产品的客户需求层次分析模型的基础上,论述应用层次分析法确定客户需求权重的方法和过程,以客户需求为依据拟定底盘产品系列型谱。在构建底盘功能体系结构的同时,将产品的功能域与产品物理域映射方法及产品子功能相关性计算、判断方法应用于底盘产品。确定底盘产品的模块划分方案并建立底盘产品族结构模型。