Stability-Considered Lane Keeping Control of Commercial Vehicles Based on Improved APF Algorithm

Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase and higher mass center.To improve the performance mentioned above comprehensively,the control strategy based on improved artificial potential field(APF)algorithm is proposed.In the paper,time to lane crossing(TLC)is introduced into the potential field function to enhance the accuracy of path tracking,meanwhile the vehicle dynamics parameters including yaw rate and lateral acceleration are chosen as the repulsive force field source.The lane keeping controller based on improved APF algorithm is designed and the stability of the control system is proved based on Lyapunov theory.In addition,adaptive inertial weight particle swarm optimization algorithm(AIWPSO)is applied to optimize the gain of each potential field function.The co-simulation results indicate that the comprehensive evaluation index respecting lane tracking accuracy and lateral stability is reduced remarkably.Finally,the proposed control strategy is verified by the HiL test.It provides a beneficial reference for dynamics control of commercial vehicles and enriches the theoretical development and practical application of artificial potential field method in the field of intelligent driving.

A Shifting Strategy for Electric Commercial Vehicles Considering Mass and Gradient Estimation

The extended Kalman filter (EKF) algorithm and acceleration sensor measurements were used to identify vehiclemass and road gradient in the work. Four different states of fixed mass, variable mass, fixed slope and variableslope were set to simulate real-time working conditions, respectively. A comprehensive electric commercial vehicleshifting strategy was formulated according to the identification results. The co-simulation results showed that,compared with the recursive least square (RLS) algorithm, the proposed algorithm could identify the real-timevehicle mass and road gradient quickly and accurately. The comprehensive shifting strategy formulated had thefollowing advantages, e.g., avoiding frequent shifting of vehicles up the hill, making full use ofmotor braking downthe hill, and improving the overall performance of vehicles.

Optimization of Engine Control Strategies for Low Fuel Consumption in Heavy-Duty Commercial Vehicles

The reduction of fuel consumption in engines is always considered of vital importance.Along these lines,in this work,this goal was attained by optimizing the heavy-duty commercial vehicle engine control strategy.More specifically,at first,a general first principles model for heavy-duty commercial vehicles and a transient fuel consumptionmodel for heavy-duty commercial vehicles were developed and the parameters were adjusted to fit the empirical data.The accuracy of the proposed modelwas demonstrated fromthe stage and the final results.Next,the control optimization problem resulting in low fuel consumption in heavy commercial vehicles was described,with minimal fuel usage as the optimization goal and throttle opening as the control variable.Then,a time-continuous engine management approach was assessed.Next,the factors that influence low fuel consumption in heavy-duty commercial vehicles were systematically examined.To reduce the computing complexity,the control strategies related to the time constraints of the engine were parametrized using three different methods.The most effective solution was obtained by applying a global optimization strategy because the constrained optimization problem was nonlinear.Finally,the effectiveness of the low-fuel consumption engine control strategy was demonstrated by comparing the simulated and field test results.

Obstructive sleep apnea among commercial vehicle drivers in Malaysia: Issues and initiatives

Obstructive Sleep Apnea (OSA) has been identified by many studies as one of the significant contributing factors for motor vehicle accidents. However, only a small number of studies have been conducted in Malaysia. Objective: This paper aims to highlight the prevalence of OSA among truck drivers and express bus drivers in Malaysia and efforts being undertaken to address issues related to OSA among commercial vehicle drivers. Methodology: Two separate studies were conducted: a cross sectional study among truck drivers and secondly among express bus drivers. The screening process for identifying the high risk group for OSA was done using Berlin questionnaire. Meanwhile, among express bus drivers, OSA was confirmed with sleep study using polysomnography test. Result: Screening of risk group of OSA among truck drivers revealed that 14.6% (19) of drivers were categorized as having high risk of OSA while 85.4% (111) having low risk of OSA. While, in another study, polysomnography test among express bus drivers showed that 83 (28.7%) had mild OSA, 26 (9.0%) had AHI moderate OSA, and 19 drivers (6.6%) severe OSA. Conclusion: This paper highlighted the issues of OSA among commercial vehicle drivers in Malaysia. With an alarming high prevalence, OSA should be a major road safety concern in this country. A special study focusing on sleep and fatigue related crashes may need to be conducted to complement the current studies and full implementation of existing efforts and initiatives to address OSA in road crashes should be realized by the relevant authorities.

数字化、电动出行和城市物流是大趋势 德国汽车工业协会(VDA)主席马蒂亚斯-魏斯曼(Matthias Wissmann)谈第66届汉诺威国际商用车展(IAA Commercial Vehicles)

今年IAA的口号“Driven by Ideas'(创意驱动)在这场全球最重要的交通、物流和移动性行业贸易展上真正得到了贯彻落实。在汉诺威,未来正在变成看得见的现实。今年IAA的口号“Driven by Ideas”(创意驱动)在这场全球最重要的交通、物流和移动性行业贸易展上真正得到了贯彻落实。在汉诺威,未来正在变成看得见的现实。整个商用车行业向IAA观众展示了创新、创造力和先锋精神。这些品质表现在332款产品的全球首发和1 00多款产品的欧洲首发。此次IAA更是决策者的贸易展,并且国际化程度前所未有。

FOTON Continues to hold its Championship as Global Largest Commercial Vehicle Manufacturer

Latest data from the China Association of Automobile Manufacturers(CAAM) shows that through 2010.China’s automobile sales surpassed 18 million, breaking the world record of annual auto sales previously held by the United States.Now that China has become a major global auto production player, how is Foton faring? CAAM statistics said production and sales volume of

Low Cost and Reusability of Launch Vehicle

This paper analyzes the launch price of the launch vehicles, domestic and abroad, studies the status and trend of the low cost launch vehicles, and introduces two measures to reduce the cost by means of evolved and disruptive technologies, utilizing the concept of low cost manufacturing and operating modes as well. This paper also analyzes the launch strategies for small satellites such as piggyback, networking launch, and single launch with a small launch vehicle(SLV). Finally, the development trend of reusable launch vehicles is discussed as well as the development prospects for China's reusable launch vehicle.

Maiden Flight of Smart Dragon 1——The Smallest Launch Vehicle in China

The Smart Dragon I(SD-I)launch vehicle is the first commercial rocket developed by China Academy of Launch Vehicle Technology(CALT),targeting to the international launch market for small satellites.As the smallest launch vehicle in China at present,SD-I is one of the most efficient solid boost rockets nation wide in terms of launch capacity.Compared with current domestic rockets,it provides remarkable access to space with a faster response,higher orbit-injection accuracy and better payload accommodation at a lower cost.On August I7,2019,SD-I completed its maiden flight and delivered three satellites into the desired Sun Synchronous Orbit(SSO)of 550 km accurately.In this article,a technical review of SD-1 is presented detailing the design concept and the use of state of the art technology throughout its development.

Safety Evaluation of Commercial Vehicle Driving Behavior Using the AHP–CRITIC Algorithm

To prevent and reduce road traffic accidents and improve driver safety awareness and bad driving be-haviors,we propose a safety evaluation method for commercial vehicle driving behavior.Three driving style clas-sification indexes were extracted using driving data from commercial vehicles and four primary and ten secondary safety evaluation indicators.Based on the stability of commercial vehicles transporting goods,the acceleration index is divided into three levels according to the statistical third quartile,and the evaluation expression of the safety index evaluation is established.Drivers were divided into conservative,moderate,and radical using K-means++.The weights corresponding to each index were calculated using a combination of the analytic hierarchy process(AHP)and criteria importance through intercriteria correlation(CRITIC),and the driving behavior scores of various drivers were calculated according to the safety index score standard.The established AHP-CRITIC safety evaluation model was verified using the actual driving behavior data of commercial vehicle drivers.The calculation results show that the proposed evaluation model can clearly distinguish between the types of drivers with different driving styles,verifying its rationality and validity.The evaluation results can provide a reference for transportation management departments and enterprises.

燃烧系统参数对商用车发动机燃烧和排放特性的影响研究

为改善商用车发动机性能,采用计算流体力学(computational fluid dynamics,CFD)模拟、正交设计等方法,针对某商用车的燃烧室结构参数设计了4种新方案,并选取油束夹角、喷雾锥角、主喷正时等3个喷油参数开展多因素影响研究。结果表明:燃烧室形状曲线向内收缩且最大半径增大的方案1燃烧室可提升缸内湍流特性,改善燃油浓度分布,使燃烧速度加快,油气混合更好,为最优方案。在喷油参数研究方案中,以碳烟(soot)排放为优化指标时,油束夹角对排放特性影响最大,最优匹配方案是油束夹角147°、喷雾锥角15°、主喷正时-1°,其缸内碳烟排放较原机下降13.91%,且NOx排放减少13.98%;以氮氧化物(nitrogen oxides,NOx)排放为优化指标时,主喷正时对排放特性影响最大,最优匹配方案是油束夹角160°、喷雾锥角25°、主喷正时-1°,其缸内NOx排放较原机降低37.79%。

基于UN R167法规的商用车直接视野3D虚拟测试方法研究

针对UN R167法规,构建商用车驾驶员直接视野的数字化模型。利用Blender仿真平台开发虚拟测试方法,求得商用车驾驶员直接视野体积。结果表明,所开发的虚拟测试方法的数据与实际尺寸测量法数据高度一致,而且能够提高测量效率,降低测量成本。

江苏省重点营运车辆技术管理现状研究

近年来,江苏省内发生多起道路运输事故。调查表明,事故发生与涉事车辆的安全技术状况均有一定的直接关系。因此,对于交通运输管理部门来说,加强道路运输企业安全监管,督促企业认真执行道路运输车辆技术管理各项标准、规范和制度就显得尤为重要。本文从车辆技术状况抽检情况、车辆检验检测信息系统应用情况、事故发生与车辆技术状况抽检对比分析、车辆技术状况管理情况四个方面对2021年度江苏省车辆技术检测情况进行分析,归纳出车辆技术状况检测与管理中存在的主要问题,并提出相应的管理措施和发展建议。

某商用汽车无法启动的故障分析

人们生活水平提高以后,使用汽车的频率也越来越高,而汽车在经过长时间的使用也必定会出现一些故障,尤其是商用汽车由于经常运输货物和大量的人员,磨损率更大,为了可以对汽车进行有效的维修和保养,需要对汽车故障进行快速的排除。本文以某商用汽车发动机无法启动为例,对其进行了故障现象和故障分析,同时也对发动机无法启动的原因进行了分析,然后通过故障分析方法对此商用汽车无法启动的故障原因进行了判断和思考。

一种商用车多轮胎压系统生产管控应用管理办法

文章简要介绍一种新型商用车多轮胎压生产装配方式,运用信息化、数字化技术,大大提高生产效率,保障售后维修中的数据同步,杜绝人为导致的维修问题。

商用电动车电池模组热管理研究

文章在已有的研究成果基础上,提出搭建特定模型分析电池模组产热情况的研究思路,并结合有限元仿真计算方法,进一步探究基于不同环境温度条件,电池在不同恒流倍率工况下的热流特性。研究结果表明,根据仿真分析结果所提出的电池模块风道改进方案,可以有效降低电池模组最高温度,同时解决内部温度分布不均匀问题,能为后续优化商用电动车电池设计提供参考。

钢-铝混合驾驶室材料-结构轻量化设计

为了得到更为完善的商用车驾驶室轻量化设计,提出了钢-铝混合驾驶室材料-结构一体化轻量化方法。首先基于灵敏度分析、等刚度近似理论与等强度理论建立了性能驱动的材料选择方法,并针对钢制驾驶室初步设计了钢-铝混合材料方案。然后通过折衷规划法的拓扑优化识别了驾驶室关键传力路径,并加强了相关结构。其次考虑驾驶室零件厚度、截面尺寸设计参数,建立了驾驶室质量、刚度及模态性能的径向基函数的代理模型,并采用多目标粒子群优化方法对驾驶室进行多目标优化设计。优化结果表明,在满足驾驶室刚度、模态和碰撞性能的要求下,驾驶室质量减轻了12.8%。该方法对钢-铝混合驾驶室轻量化有实际的工程指导价值。

基于生命周期的轻型商用货车轻量化碳排放研究

以某轻型商用货车为研究对象,根据生命周期理论构建以汽车生产过程中的原材料获取、生产运输、零部件制造和车辆装配阶段为边界的碳排放量计算模型,探讨了轻量化措施中所涉及材料的生命周期碳排放差异,对比分析了该车轻量化前后的碳排放量。结果表明,替代材料铝合金、镁合金、碳纤维增强塑料的生命周期碳(CO_(2))排放量显著高于被替代材料钢和铸造铁,分别为6.23 kg/kg(锻造铝合金)、6.92 kg/kg(铸造铝合金)、14.76 kg/kg(车用镁合金)、20.2 kg/kg(车用碳纤维增强塑料)、2.85 kg/kg(普通钢)、0.67 kg/kg(不锈钢)和0.81 kg/kg(铸造铁);轻量化后的动力总成系统、传动系统、底盘和车身部分的碳(CO_(2))排放量分别增加了0.57%、525.51%、11.57%和33.29%,车辆生命周期碳(CO_(2))排放量增加了36.22%;钢和铝生命周期碳(CO_(2))排放量的降低对于轻量化前后车体部分的减碳效果均较明显。

基于Cruise的重型商用车性能匹配分析

针对重型商用车动力系统开发周期长、成本高的问题,该文首先参考法规基于MATLAB编写程序生成需要的换挡策略,再通过AVL Cruise对整车性能匹配进行建模和仿真分析,得到油耗、动力性都满足要求的最优动力方案,并与该方案对应的实测值进行对比分析。结果表明,仿真结果与实测结果基本吻合,模型仿真可以代替实测对整车性能提前评估,缩短产品开发周期和成本。

商用车电控转向系统的发展现状与趋势

商用车转向系统的电控化是实现商用车节能化和智能化的必由之路,为此商用车转向系统从传统的液压助力转向系统发展到以电液耦合助力转向系统为代表的电控转向系统。本文将对商用车电控转向技术进行综述,从电控转向系统的典型构型、智能转向控制和功能安全设计3个方面对商用车电控转向技术的研究进行梳理,总结电控转向技术的重点研究领域和未来发展方向。梳理总结发现:(1)在系统构型方面,商用车电控转向系统以电液耦合转向助力技术为主,着重于实现商用车智能转向功能,同时兼顾节能化需求;商用车电动助力转向系统是未来理想的电控转向技术方案。(2)在智能控制方面,为了适应商用车智能化的发展,转向执行控制着重于解决液压系统所造成的非线性与时滞性问题以及轨迹跟随过程中的横向动力学控制难题;辅助驾驶功能着重于克服液压系统的非线性导致的转向力矩不连续以及人机控制权的分配;自动驾驶功能着重于提升安全性与燃油经济性。(3)在系统功能安全设计方面,商用车电控转向系统着重于设计符合功能安全标准的故障诊断与容错控制策略。