搅拌摩擦焊接技术在汽车制造中的应用研究

搅拌摩擦焊接是固相连接技术，焊接过程中形成精细的锻造组织，具有较高的接头性能。在介绍搅拌摩擦焊技术的基础上，对该技术在汽车制造业中的应用进行了探讨。对搅拌摩擦点焊技术进行了介绍。由于搅拌摩擦点焊具有成本低、耗能少等优势，可完全替代传统点焊方法用于汽车制造。     

双向自增力式制动器摩擦模型的研究

为了科学准确地描述双向自增力式制动器的摩擦系数和速度温度等因素间的关系。综合考虑静摩擦到动摩擦非线性阶段,动摩擦速度稳态阶段以及动摩擦随温度变化阶段,建立了制动器制动过程的摩擦模型,并用仿真曲线与制动过程曲线对比,验证了摩擦模型。     

Estimation of the tyre–road maximum friction coefficient and slip slope based on a novel tyre model

In this article, a new approach to estimate the vehicle tyre forces, tyre–road maximum friction coefficient, and slip slope is presented. Contrary to the majority of the previous work on this subject, a new tyre model for the estimation of the tyre–road interface characterisation is proposed. First, the tyre model is built and compared with those of Pacejka, Dugoff, and one other tyre model. Then, based on a vehicle model that uses four degrees of freedom, an extended Kalman filter (EKF) method is designed to estimate the vehicle motion and tyre forces. The shortcomings of force estimation are discussed in this article. Based on the proposed tyre model and the improved force measurements, another EKF is implemented to estimate the tyre model parameters, including the maximum friction coefficient, slip slope, etc. The tyre forces are accurately obtained simultaneously. Finally, very promising results have been achieved for pure acceleration/braking for varying road conditions, both in pure steering and combined manoeuvre simulations.     

数学模型在现代汽车模具设计制造中的应用

对数学模型在现代汽车模具设计和加工中的应用进行了阐述,使读者对现代模具加工的过程和特点有初步的了解。     

Freight cars shunting impacts analysis using an improved dynamic model of friction draft gear

In this study, simulations of shunting impacts for groups of freight cars that include up to six cars are considered. The simulation technique employs a white-box improved dynamic model of friction draft gear considering all its components and detailed finite element models of the freight cars. The key differences between the one-to-one shunting impact and the impact of long groups of cars in terms of features of the draft gear deflections and the coupler force time history are discussed. We present an example of dynamic finite element analysis for the car body using the coupler force time history obtained from the shunting impact simulation.     

轻型汽车ESC国家标准研究与制定

为使汽车行业充分理解轻型汽车电子稳定性控制系统（ESC）国家标准,引导和规范ESC测试评价,文章对轻型汽车ESC全球技术法规的主要内容和特点进行系统剖析,针对ESC过度转向评价和路面摩擦因数测定开展验证试验,并探索不足转向试验方案。在ESC国家标准中明确了路面摩擦因数测定方法,并通过冰雪路面上的双移线试验和稳态圆周试验对ESC不足转向特性进行评价。轻型汽车ESC国家标准弥补了全球技术法规在不足转向评价上的不足,为我国规范与完善ESC性能测试奠定了基础。     

富康轿车等速万向节传动轴国产化关键技术的研究

对富康轿车等速万向节传动轴国产化时鉴定试验中的各个相关技术问题进行了研究。利用Palmgren的方程式和累积损伤原理并结合富康轿车的整车参数,对等速万向节尺寸的选择是否合理进行了校核;提出了台架试验方法和试验设备要求;利用富康轿车变速器的载荷数据计算了耐久性试验指标以适应各供应商不同的试验设备情况;最后对试验结果进行了分析和描述。     

制动器台试减速度评定及制动衬片摩擦系数允差的确定

本文分析了制动器台试减速度允差评定方法，为了有效制动和改善轿车制动稳定性，讨论了摩擦材料的摩擦系数与制动减速度和前后制动分配比的关系，根据设计要求之制动减速度和制动力分配比，提供摩擦系数计算方法和顺序，用于合理确定台试时的摩擦系数允差，本文可供制动器设计和摩擦材料选用作参考。     

Experimental study on performance of automotive air conditioning system using R-152a refrigerant

Recently, as climate changes have manifested worldwide, every country is making efforts to prevent ozone depletion and global warming. In the automotive industry, R-134a refrigerant is widely used in air conditioning systems because it has zero ozone depletion potential (ODP). Unfortunately, its global warming potential (GWP) is high. Therefore, alternative refrigerants are needed as a replacement for R-134a. R-152a is considered to be one of the better alternative refrigerants due to zero ODP and low GWP. In this paper, the performance of an automotive air conditioning system using R-134a and one using R-152a are compared experimentally at the bench level. The experimental apparatus simulated a real automotive air conditioning system consisting of a cabin and engine room structure. The cooling capacity, condensing capacity, coefficient of performance (COP) and power consumption characteristics of the automotive air conditioning system are evaluated by changing the air velocity entering the condenser and the compressor rotation speed with the optimized refrigerant charge amount. Also, the performance of the R-152a system was investigated by changing the thermostatic expansion valve which is set of values. The results of this study show that the R-152a system is slightly better than the R-134a system, not only under driving conditions but also under idling condition. R-152a refrigerant thus shows promise as an alternative refrigerant to replace the current standard, R-134a, in automotive air conditioning systems.     

Flexible multibody simulation of automotive systems with non-modal model reduction techniques

The stiffness of the body structure of an automobile has a strong relationship with its noise, vibration, and harshness (NVH) characteristics. In this paper, the effect of the stiffness of the body structure upon ride quality is discussed with flexible multibody dynamics. In flexible multibody simulation, the local elastic deformation of the vehicle has been described traditionally with modal shape functions. Recently, linear model reduction techniques from system dynamics and mathematics came into the focus to find more sophisticated elastic shape functions. In this work, the NVH-relevant states of a racing kart are simulated, whereas the elastic shape functions are calculated with modern model reduction techniques like moment matching by projection on Krylov-subspaces, singular value decomposition-based reduction techniques, and combinations of those. The whole elastic multibody vehicle model consisting of tyres, steering, axle, etc. is considered, and an excitation with a vibration characteristics in a wide frequency range is evaluated in this paper. The accuracy and the calculation performance of those modern model reduction techniques is investigated including a comparison of the modal reduction approach.     

汽车电器低速网络控制系统的研制

按照区域自治原则，将汽车电器划分为十个子区，每个子区拥有一个ECU。所有ECU经双绞线联接成网络，从而构成了汽车电器低速网络系统。对这一系统拓扑形式、通讯协议、系统控制等进行了较为深入的探讨。     

An improved dynamic model of friction draft gear with a transitional characteristic accounting for housing deformation

A white-box friction draft gear model has been developed. All components of the draft gear are considered. The distinctive feature of the model, as compared to its predecessor, is the transitional characteristic, which accounts for the effect of elastic deformations of the draft gear housing on the position of the friction wedge system components under loading. The adjustment of the model parameters for improved agreement with experimental data is discussed. The new model can be used in the simulation of shunting impacts for single cars and car groups represented by detailed finite-element models. An example of the simulation is presented and compared with experimental data obtained using a shunting hump test stand.     

基于期望间距的车辆跟驰模型的建立

以“期望间距”为基准参理，考虑驾驶员的心理和生理因素，建立了车辆跟驰模型，为研究驾驶行为提供了一种新的思路。     

汽车工业无损检测技术的发展

从汽车零部件的使用性能和商品性能方面论述了无损检测技术在汽车工业中的重要地位，它是现代汽车工业的基础。评述了国内外汽车工业无损检测技术的现状，并根据未来汽车发展方面分析了无损检测发展的趋势，以及我国汽车工业无损检测技术发展的策略。     

“最小系统”在汽车电子V型开发流程中的应用

随着汽车电子控制系统复杂性的不断提高,为保证产品质量,当今业界的ECU设计普遍采用基于V型开发流程.文章在分析ECU系统架构的基础上,提出了ECU“最小系统”的概念,通过构建“标杆模块”与“桩模块”,实现了对ECU“最小系统”的测试.实践表明,ECU“最小系统”的引入,提高了开发效率,降低了项目成本.     

一种实用新型底盘装配支撑结构的开发

底盘装配支撑应用于商用汽车底盘装配与工程机械车辆底盘装配,属于装配线附属工装设施.底盘装配支撑结构的适用性、可靠性、耐久性关系到底盘装配线的运行安全与运行效率.文章结合公司在建底盘装配线工艺验证问题整改,对底盘装配支撑结构进行优化,开发出一种适用于驱动桥桥包支撑的实用新型支撑结构.     

塑料改性技术的发展及其在汽车上的应用

通过塑料改性技术在汽车及塑料行业中的应用分析，重点阐述了塑料改性技术研发重点及面临的突破问题。     

Teamcenter10.0在汽车车桥集成开发中的应用

Teamcenter10.0软件的实施使汽车车桥产品开发处于平台化、标准化、流程化的工作模式,全面支撑企业基于APQP理念的项目管控模式;实现了与ERP、NX、CAD及OFFICE软件的集成,建立了系统集成应用环境,形成企业信息网,大大降低人工干预、管控的风险;实现了汽车车桥产品研发中全阶段的监控、任务跟踪,降低了产品开发风险、开发周期和开发成本,提升了项目开发效率,能够满足主机厂项目及产品开发理念及节点要求,提升顾客满意度。     

Development and validation of a numerical model for predicting forklift truck tip-over

The aim of this paper is to present the dynamic behaviour modelling performed for a forklift truck and the validation of this model. The intention is to develop a permanent tool allowing both common and critical driving situations (especially that of lateral tip-over) to be simulated for this type of vehicle. The medium-term aim is to use this model as a tool to facilitate designing, training and preparing safety standards with a view to reducing the number of accidents related to this machine, which, on average, still cause nearly 10 deaths each year. This paper describes the forklift truck mechanical model and the tyre model. A Pacejka's lateral tyre model was used and integrated into the forklift truck model. The interacting forces and moments between the wheels and the ground are, therefore, computed at all times. Test bench-measured data, characteristic of the dynamic behaviour of several tyres, were used to identify the parameters of the Pacejka model. We studied the limits of this model adapted in this case to tyres with characteristics different from those of the car sector. Track testing was performed using a safe-test forklift truck. The purpose of these tests was to measure trajectory characteristics (velocity, position, acceleration and slip angle) and to compare them with model-based predictions, allowing validation of the robustness and accuracy of this model. Situations involving partial (up to 15°) tip-over were included. The quantities measured during testing were compared with the calculation results obtained for identical driving configurations. There was a close calculation/measurement correlation when performing a wide ‘J-turn’ (with and without tip-over) when following circular or slalom trajectories. The calculation/measurement correlation was less close when the forklift truck performed a sharp ‘J-turn’, for example. Model limits can be derived from the observations, data processing and calculations.