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421.
介绍一款兼容硬线连接与CAN总线两种数据采集传输系统的组合仪表平台,提供通用化、低成本的仪表指示解决方案,并对设计原理及实施细则进行论述。  相似文献   
422.
对某型军用移动电站75 kW单轴承无刷发电机跨接线断裂问题进行分析,通过采用改进跨接线绑扎位置设计、严控同心度指标、限定电磁线折弯次数等措施,有效解决了该型发电机转子绕组跨接线断裂问题,提高了该型发电机工作的可靠性。  相似文献   
423.
A set of scaling factors has been introduced by Pacejka [Pacejka, H.B., 2002, Tyre and Vehicle Dynamics (Oxford: Butterworth Heinemann Editions)] into his Magic Formula tyre model to take into account the influence of a number of external overall parameters such as road roughness, weather conditions, suspension characteristics and so on. These scaling factors are important for a correct prediction of tyre–road contact forces, but are not a function of the tyre itself. Changing the point of view, one could say that scaling factors should remain constant for different tyres on the same circuit, with the same weather conditions and with the same car. After characterizing different tyres through indoor tests (that do not consider external overall parameters) and after having identified Pacejka’s coefficients with scaling factors equal to one, several outdoor experimental tests have been carried out to assess the influence of vehicle and road surface conditions on scaling factors. These experimental data allowed us to identify, through a minimization approach, the ‘best’ set of Pacejka’s scaling factors for that vehicle and for that tyre on that track. Scaling factors for equal track and vehicle but different tyres were compared to check whether their values remained constant. To access the validity of scaling factors, a comparison between experimental data, collected on an instrumented passenger car, and MB simulations considering unity and identified scaling factors’ values, were carried out. All experimental data shown in this article come from tests carried out within the VERTEC project, a European founded research project (Task 2.a and 2.b) that puts together knowledge coming from vehicle manufacturers (Volvo, Porsche and Centro Ricerche Fiat CRF), tyre manufacturers (Pirelli and Nokian Tyres), control logic manufacturers (Lucas Varity GmbH), road maintenance experts (Centres d’Études Techniques de l’Équipement CETE), transport research organizations (Transport Research Laboratory TRL, Swedish National Road and Transport Research Institute VTI) and universities (Helsinki University of Technology HUT, Politecnico di Milano and University of Florence UNIFI).  相似文献   
424.
This article presents a model for solving solid–fluid interactions in vehicles carrying liquids. A tractor–semitrailer model is developed by incorporating suspension systems and tire dynamics. Owing to the solid–fluid interaction, equations of motion for the vehicle system are coupled. To simplify the complicated solution procedure, the coupled equations are solved separately using two different codes. Each code is analyzed separately; but as the parameters of the two codes depend on each other, the codes must be connected at the end of each time step. To determine the dynamic behavior of the system, different braking moments are applied. As the braking moments increase, braking time decreases. However, it turns out that increasing the braking moment to more than a certain level produces no significant results. It is also shown that vehicles carrying fluids need a greater amount of braking moments in comparison to vehicles carrying solids during braking. In addition, as the level of the fluid inside the tanker increases, from one-third to two-third of the tanker’s volume, the sloshing forces applied to the tanker’s walls increase. It was also concluded that the strategy used in this article to solve for the solid–fluid interaction by incorporating vehicle dynamic effects represents an effective method for determining the dynamic behavior of vehicles carrying fluids in other critical maneuvers.  相似文献   
425.
介绍了铝合金型材驾驶室的优点,分析了铝合金型材的挤压工艺及焊接工艺性。  相似文献   
426.
对SS4B型机车车体结构作了简要介绍,分析了SS4B型机车车体设计中的一些不足之处,提出了相应的改进措施,并将其应用到新造SS4B型机车车体设计中。  相似文献   
427.
文章介绍了深圳地铁一号线续建工程车辆司机室视野分析及其相关的司机座椅高度、位置确定方法,司机操纵台高度设计和前窗大小计算方法。  相似文献   
428.
娄云  朱命怡 《汽车电器》2004,(9):42-43,45
论述了上海别克轿车发动机点火控制系统各传感器和控制模块的功能、工作原理、故障码设置及故障诊断方法。  相似文献   
429.
堆载预压法处理道路软基的效果分析   总被引:2,自引:0,他引:2  
本文通过广州市一条堆载预压 7年的道路工程资料研究 ,发现软基区填方路堤在 2 .5~ 3.0m间存在一临界高度。路堤低于临界高度时 ,路基沉降量随路堤增高增加缓慢 ;路堤高于临界高度时 ,路基沉降量随路堤增高迅速增加 ;但路堤高度一定时 ,软基沉降量随软土层厚度变大增加缓慢。堆载 7年后 ,在原埋深 3.0m以上的软土的物理力学性质改善 2 7%~ 6 9% ,3.0m以下软土的物理力学性质改善 1%~ 5%。  相似文献   
430.
车身结构件多步冲压工艺数值模拟   总被引:4,自引:0,他引:4  
陈炜  杨继昌  仲志刚  方禾  朱国璋 《汽车工程》2003,25(5):518-521,F003
分析了左后悬挂架形成特点,采用两步拉延方式完成成形;然后确定首次拉延的四种方案,研究不同变形形式和变形量对后继拉延所造成的成形质量的影响;通过数值模拟结果中的FLD曲线、材料厚度分布图、最大主应变分布图和拉延成形变形裕度,研究车身结构件多步冲压工艺设计。  相似文献   
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