Intelligent Electronic Systems in Commercial Vehicles for Enhanced Traffic Safety

Looking at the future trends of the road traffic, one will recognize that the commercial vehicle participation will not decrease, although it is required from the environmental and social viewpoints. The reason is that the other means of freight transport (water, railway, air) do not provide the same flexibility as the road transport, and direct business interest of those companies, who are using this transport form is larger than the eventual loss caused by the penalties to be paid (taxes, compensation of higher axle load). This conflict is hard to solve, but the effect can be minimized. The commercial vehicle industry attempts to introduce systems to the vehicles, which are targeting on reduction of the environmental impacts caused by heavy vehicles. These systems, which are named generally as “intelligent chassis systems”, electronically control the operation of the chassis subsystems (engine, transmission, brake, suspension) and co-ordinate their operation on a higher level (vehicle controller, intelligent control systems, such as adaptive cruise control, video camera based lane change recognition system, etc.). This paper reviews the state-of-the-art of the commercial vehicle chassis systems, and tries to project their future development.     

智能网联汽车节能优化关键问题与研究进展

汽车保有量的增加和能耗排放法规日益严格的限制给车辆节能减排提出了巨大挑战，网联化、智能化和电气化是提高未来交通效率和减少公路能源消耗的三大支柱。为了全面了解智能网联汽车节能减排的前沿问题与研究进展，对当前经济驾驶领域的重点问题进行了总体概述。首先，从广义的能量转换角度总结了智能车辆节能优化技术的本质和3个过程，其中Wheels to Distance环节的车辆系统优化是挖掘汽车节能潜力的重要一环，针对其介绍了智能网联汽车节能优化问题的基本数学原理；其次，从智能运输系统的各类非同源异构数据出发，分别从人-车交互、车-车通信、车-路感知三方面阐述来源于"人-车-路"交互体系的智能信息与数据；然后，针对单车智能网联环境下的多维度信息与先进控制技术相结合的关键问题，从考虑道路坡度预测巡航控制、跟车工况预测巡航控制、智能辅助驾驶和车道变换等应用场景进行具体介绍；针对"人-车-路-云"多源异构环境下车辆行为协同节能关键科学问题，从经济驾驶、多车协同节能、道路交叉口车路协同节能和车云协同节能等方面详细介绍研究现状；并进一步介绍电气化公路系统的前瞻性研究，说明融合智能化信息的E-highway节能潜力和智能重型商用车协同节能的未来发展趋势。最后，总结并梳理智能化信息对于提升车辆节能的重要影响，并展望了其在理论与实际层面遇到的挑战。     

商用车底盘线控技术研究现状及应用进展

底盘线控技术是实现商用车自动驾驶和辅助驾驶功能的关键基础技术,是当今汽车行业的研发热点。底盘线控技术包括线控执行系统和线控集成控制技术两大部分。分别对商用车的线控转向、线控制动、线控悬架、线控驱动和线控换挡等线控执行系统,以及自动紧急制动 （Autonomous Emergency Braking,AEB） 系统、自适应巡航 （Adaptive Cruise Control,ACC） 系统和车道保持辅助 （Lane Keeping Assist,LKA） 系统等线控集成控制技术的构成、控制原理与研究应用现状进行了概述,重点分析了商用车各类构型的线控转向和线控制动系统及其应用场景。结合最新发布的国家智能底盘技术路线框架图和商用车未来的客户需求,给出了商用车线控底盘各技术方向的发展趋势,为商用车线控底盘技术发展提供了参考。     

Connected variable speed limits control and car-following control with vehicle-infrastructure communication to resolve stop-and-go waves

The vision of intelligent vehicles traveling in road networks has prompted numerous concepts to control future traffic flow, one of which is the in-vehicle actuation of traffic control commands. The key of this concept is using intelligent vehicles as actuators for traffic control systems. Under this concept, we design and test a control system that connects a traffic controller with in-vehicle controllers via vehicle-to-infrastructure communication. The link-level traffic controller regulates traffic speeds through variable speed limits (VSL) gantries to resolve stop-and-go waves, while intelligent vehicles control accelerations through vehicle propulsion and brake systems to optimize their local situations. It is assumed that each intelligent vehicle receives VSL commands from the traffic controller and uses them as variable parameters for the local vehicle controller. Feasibility and effectiveness of the connected control paradigm are tested with simulation on a two-lane freeway stretch with intelligent vehicles randomly distributed among human-driven vehicles. Simulation shows that the connected VSL and vehicle control system improves traffic efficiency and sustainability; that is, total time spent in the network and average fuel consumption rate are reduced compared to (uncontrolled and controlled) scenarios with 100% human drivers and to uncontrolled scenarios with the same intelligent vehicle penetration rates.     

智能汽车自动紧急转向避撞的跟踪控制方法对比研究

为了提高智能汽车的主动安全性,提出3种不同的自动紧急转向避撞跟踪控制方法。首先建立汽车避撞简化模型,对制动、转向及两者相结合的3种不同避撞方式进行对比分析。其次,为深入研究汽车避撞过程中的实际响应,建立包含转向、制动及悬架3个子系统耦合特性的底盘18自由度统一动力学模型,并进行相关试验验证。随后构建智能汽车自动紧急转向避撞控制框架,对五次多项式参考路径和七次多项式参考路径的横摆角速度和横摆角加速度进行对比分析。接着以线性2自由度转向动力学模型为参考对象,对最优控制四轮转向、最优控制前轮转向、前馈与反馈控制相结合的前轮转向3种不同的跟踪控制系统分别进行设计。最后,以汽车底盘18自由度统一动力学模型为研究对象,对上述3种避撞控制系统进行仿真试验对比分析。研究结果表明：与制动避撞相比而言,转向避撞所需的纵向距离有较大降低,随着车速的增加和路面附着系数的越低,效果越明显;七次多项式参考路径比五次多项式参考路径的避撞过渡过程更为平缓,当实际车速与控制器所用车速不一致时,前者避撞性能表现更优;最优四轮转向控制系统在高、低2种不同附着路面都具有较好的避撞效果,最优前轮转向控制系统次之,而前馈与反馈相结合的前轮转向控制系统在低附着路面上则表现出严重的失稳。     

车-车协同下无人驾驶车辆的换道汇入控制方法

多车协同驾驶是智能车路系统领域的研究热点之一,可有效降低道路交通控制管理的复杂程度,减少环境污染的同时保障道路交通安全。基于多车协同驾驶控制结构,提出了一种无人驾驶车辆换道汇入的驾驶模型及策略,系统分析了多车协同运行状态的稳定条件。在综合分析无人驾驶车辆换道汇入的协作准则、安全性评估后,基于高阶多项式方法,结合车辆运行特性,通过引入乘坐舒适性的指标函数,设计得到无人驾驶车辆换道汇入的有效运动轨迹。通过研究汇入车辆与车队中汇入点前、后各车辆的运动关系,详细分析车辆发生碰撞的类型和影响因素,给出避免碰撞的条件准则,从而确保无人驾驶车辆汇入过程中多车行驶的安全性和稳定性。基于车辆运动学建立车辆位置误差模型,结合系统大范围渐进稳定的条件,选取线速度和角速度作为输入,应用李雅普诺夫稳定性理论和Backstepping非线性控制算法,设计了无人驾驶车辆换道汇入后的路径跟踪控制器。仿真试验和实车试验结果表明：所设计的换道汇入路径是可行、安全的,控制器具有良好的跟踪效果,纵向和横向的距离误差在15 cm以内,方向偏差的相对误差在10%以内。研究结果为智能车路系统中的多车状态变迁与协同驾驶研究提供了参考,可服务于未来道路交通安全设计和评价。     

智能汽车横纵向运动控制方法综述

在我国随着人民生活水平的提高,车辆保有量也在呈倍速增长,进而引起了大量的交通安全问题,其中由驾驶员操作不当引起的交通事故约占所有交通事故的75%。而汽车的智能化发展可以很好地解决此类交通安全问题。智能汽车的核心技术主要包括环境感知、行为决策及运动控制三方面。其中运动控制作为智能汽车核心技术之一,有着重要的研究意义。智能汽车的运动控制包括横向控制和纵向控制两部分,对汽车横、纵向运动控制中的多种方法进行了分析介绍,包括模型预测控制、模糊逻辑控制、神经网络的自适应滑膜控制、直接式控制和分层式控制;同时介绍了横纵向耦合实现运动控制的重要性,并分析了其研究现状;最后,对智能汽车运动控制的后续发展方向进行了展望,有助于智能汽车运动控制的进一步优化发展。     

机动车环保清单系统信息处理技巧之应用

按照《大气污染防治法》规定,机动车和非道路移动机械生产企业,应当向社会公开其生产机动车的环保信息[1],包括排放检验信息和污染控制技术信息,并对信息公开的真实性、准确性、及时性、完整性负责。由于机动车信息公开编号生成的数据量大,人工完成需耗费很大精力,文章将探讨如何借助智能打印系统以最少、最易的条件,准确判定信息公开编号及对应信息,并对后台运行的四个信息处理技巧进行可行性分析;以期能够提升机动车环保信息公开效率。     

Modeling and Analysis of Automotive Antilock Brake Systems Subject to Vehicle Payload Shifting

The steerability and stability of vehicles must be maintained during emergency stopping and evasive driving maneuvers on degraded road surfaces. The introduction of antilock brake and traction control systems (ABS/TCS) has expanded the envelope of safe vehicle operation for the majority of drivers. These mechatronic systems combine an electronic controller with wheel speed sensors, an electro-mechanical hydraulic brake actuator, and in some instances, engine intervention through the engine control unit, to regulate wheel slip. The development of ABS systems has traditionally depended on extensive in-vehicle testing, at cold weather proving grounds, which contribute to lengthy product development cycles. However, recent attention has been focused on the use of simulation and hardware-in-the-loop strategies to emulate test conditions in a controlled setting to shorten product design time and methodically address critical safety issues. In this paper, the effect of transient load shifting due to cargo movement on ABS performance in light-duty vehicles will be investigated. Analytical and empirical mathematical models are presented to describe the chassis, tire/road interface, wheel, brake modulator, and cargo dynamics. Two strategies, a model-free table lookup and model-based discrete nonlinear controller, are presented to regulate the ABS modulator's operation. These vehicle and controller dynamics have been integrated into a simulation tool to investigate the effect of transient weight transfers on the vehicle's overall stopping distance and time. Representative numerical results are presented and discussed to quantify the ABS systems' performance for various loading and operating conditions.     

Development of advanced driver assistance systems with vehicle hardware-in-the-loop simulations

This paper presents a new method for the design and validation of advanced driver assistance systems (ADASs). With vehicle hardware-in-the-loop (VEHIL) simulations, the development process, and more specifically the validation phase, of intelligent vehicles is carried out safer, cheaper, and is more manageable. In the VEHIL laboratory, a full-scale ADAS-equipped vehicle is set up in a hardware-in-the-loop simulation environment, where a chassis dynamometer is used to emulate the road interaction and robot vehicles to represent other traffic. In this controlled environment, the performance and dependability of an ADAS is tested to great accuracy and reliability. The working principle and the added value of VEHIL are demonstrated with test results of an adaptive cruise control and a forward collision warning system. On the basis of the 'V' diagram, the position of VEHIL in the development process of ADASs is illustrated.     

Development of advanced driver assistance systems with vehicle hardware-in-the-loop simulations

This paper presents a new method for the design and validation of advanced driver assistance systems (ADASs). With vehicle hardware-in-the-loop (VEHIL) simulations, the development process, and more specifically the validation phase, of intelligent vehicles is carried out safer, cheaper, and is more manageable. In the VEHIL laboratory, a full-scale ADAS-equipped vehicle is set up in a hardware-in-the-loop simulation environment, where a chassis dynamometer is used to emulate the road interaction and robot vehicles to represent other traffic. In this controlled environment, the performance and dependability of an ADAS is tested to great accuracy and reliability. The working principle and the added value of VEHIL are demonstrated with test results of an adaptive cruise control and a forward collision warning system. On the basis of the ‘V’ diagram, the position of VEHIL in the development process of ADASs is illustrated.     

Modeling and control of an anti-lock brake and steering system for cooperative control on split-mu surfaces

The brake and steering systems in vehicles are the most effective actuators that directly affect the vehicle dynamics. In general, the brake system affects the longitudinal dynamics and the steering system affects the lateral dynamics; however, their effects are coupled when the vehicle is braking on a non-homogenous surface, such as a split-mu road. The yaw moment compensation of the steering control on a split-mu road is one of the basic functions of integrated or coordinated chassis control systems and has been demonstrated by several chassis suppliers. However, the disturbance yaw moment is generally compensated for using the yaw rate feedback or using wheel brake pressure measurement. Access to the wheel brake pressure through physical sensors is not cost effective; therefore, we modeled the hydraulic brake system to avoid using physical sensors and to estimate the brake pressure. The steering angle controller was designed to mitigate the non-symmetric braking force effect and to stabilize the yaw rate dynamics of the vehicle. An H-infinity design synthesis was used to take the system model and the estimation errors into account, and the designed controller was evaluated using vehicle tests.     

A perspective on ITS deployment

The intelligent transport systems (ITS) deployment begins with implementation of traffic control signals and traffic management on a road network. The next stage is the provision of traffic information to drivers. The third stage is the decision and operation assistance to drivers for safe driving. It will take time to reach the final stage of a fully automated driving because of the difficulties of getting social acceptance. Another final figure of ITS is that all transportation modes are integrated and provide continuous transportation service to users from door to door. Mobile information terminals such as cellular phones and motor vehicles will function as well as ordinary offices and homes. Then the ITS as an information system will be integrated into a general social information system.     

面向智能车辆的现役道路设施行驶适应性研究综述

为了总结面向智能车辆的现役道路设施行驶适应性，即现役道路基础设施承载智能车辆行驶的适宜程度，阐述自主智能驾驶定义与驾驶自动化等级分类，在此基础上剖析不同等级间的人机功能差异，并分别从感知层、感知-决策层、决策-控制层探讨与道路设计要素相关联的人机功能差异，通过归纳总结智能车辆与道路几何要素、路面性能及其他道路要素(如道路标线)的相互作用机制研究，从道路工程角度及其他道路要素方面回顾该领域的研究现状，指出存在的问题和未来发展方向。研究结果表明：相比传统车辆，配置高等级自动驾驶系统的智能车辆对现役道路设施行驶适应性最高，主动安全系统次之，而驾驶辅助及有条件自动驾驶系统适应性不足。而目前研究主要问题包括：难以归纳、标定不同驾驶自动化等级间的人机功能差异及其对于道路设计参数的需求设计值；测试道路场景条件过于理想，考虑的驾驶自动化等级单一，试验规模和样本有限；道路几何、路面性能以及道路标志、标线等道路要素与智能车辆间的相互作用机制研究不足，缺乏与不同道路场景相匹配的智能车辆驾驶特征数据的获取手段。因此建议：重视并推动与道路设计要素相关联的关键人机功能差异指标信息共享；联合高保真且可交互的道路场景、高精度感知传感器物理模型、车辆动力学模型及微观交通流模型，利用测试场景自动化生成、极限工况场景搜寻与泛化等技术开展智能驾驶虚拟测试，突破现有研究的深度和广度；探索反映不同等级智能车辆的道路行驶适应性特征指标与评价标准，精准、有效地评估预测复杂道路场景及不利道路条件下的行驶适应性。     

纯电动商用车异质队列的多目标控制

队列行驶的研究能有效解决商用车货运安全、能耗浪费和环境污染等问题,但现有研究多基于单一跟车目标控制的匀质队列,这在货运场景中无法达到很好的控制效果。本文中构造了纯电动异质商用车队列,为其设计了分布式非线性模型预测控制器。根据道路环境信息和车辆跟车、安全、舒适和节能等特性,分别建立了领航车和跟随车的控制器模型,实现异质队列的多目标控制。为验证所提出控制方法的有效性,由5辆动力学特性相异的商用车组成队列,并搭建了控制仿真平台进行Trucksim/Simulink联合仿真。结果表明,本文中提出的控制算法能有效实现异质商用车队列的多目标控制,与PID定速巡航控制相比,能耗可降低5.3%以上。     

Comparison of driving characteristics between drivers in Korea and in the united states of America based on driver-vehicle interaction field database

Research and development involving intelligent vehicles of today is geared to safe, driver-friendly and sensitive vehicles that provide a driver with a pleasant and convenient driving environment while preventing him or her from possible risks of accident. In developing convenient and safe vehicles, research on drivers’ driving patterns, reactions and state characteristics depending on road conditions in actual field is essential in order to devise more driver-friendly intelligent vehicles. This paper describes how a driver-vehicle interaction (DVI) field database is built in order to obtain a driver’s input in normal road driving condition on highways, country roads, and city roads, and his or her state information, as well as data on the vehicle and traffic conditions. And the newly built database is compared with the RDCW FOT database established by UMTRI of the US for analysis to suggest that the driving tendencies of drivers in Korea and the road driving conditions are not the same as those in the US, reconfirming the need to establish a DVI field database, which will be used for the development of intelligent vehicles suitable for the Korean environment. The DVI data collected from actual driving in field are anticipated to be widely utilized as basic data for research on various intelligent driving safety systems, advanced driver assistance systems (ADAS) and human-vehicle interface (HVI) that are suitable for the driving environment in Korea.     

智能车辆机器视觉发展近况

简要回顾了机器视觉的早期发展，从简单的特定场合应用到模拟人眼的复杂系统设计，介绍了机器视觉产品在智能汽车上的应用情况，分析了世界各国在车用机器视觉技术领域研究开发情况以及未来发展趋势。     

中国智慧公交示范现状分析及展望

智慧公交示范属于智能网联示范中的特色应用场景,也是智能网联开放道路示范的先行力量。本文梳理了我国现有典型智慧公交示范情况,分析其共性特点及存在问题,并对未来发展进行了展望。旨在从智慧公交视角窥见整体智能网联汽车产业发展进程,促进智能网联汽车从封闭走向开放、从示范应用走向商业化推广。     

智能路面发展与展望

为了促进智能路面的发展，综述了智能路面各项技术的研究进展和发展趋势。首先提出了智能路面的定义，在此基础上明确了智能路面的体系架构，包括路面信息感知获取层、信息集成处理层、综合服务层和能量供给层；重点介绍了智能路面信息采集技术、信息管理与分析技术、能量收集与利用技术、自我调节技术和基于智能路面的车路协同技术等关键技术的发展现状，讨论了智能路面的设计和建造方法；最后提出了智能路面现有研究存在的问题和不足，并对其今后的发展做出展望。研究结果表明：智能路面是由特定的结构材料、感知网络、信息中心、通信网络和能源系统组成，具有多种智能，并且能够为人、车、环境提供服务的道路路面；智能路面的发展将有助于充分发挥道路自身潜力和适应未来的交通工具；在路面信息的采集过程中，传感器在耐久性和实用性等方面存在的技术难题仍需进一步解决；智能路面的各种能量收集和自我调节技术应着重解决低成本和高性能的问题；物联网、大数据、云计算和各种人工智能方法在智能路面的监测和管理过程中具有广阔的应用前景；智能路面作为一种新型的道路路面，其设计和施工可以结合建筑信息模型（BIM）、模块化施工、3D打印和智能压实技术，集合成一套新的建造工艺。     

Literature review and fundamental approaches for vehicle and tire state estimation*

ABSTRACT

Most modern day automotive chassis control systems employ a feedback control structure. Therefore, real-time estimates of the vehicle dynamic states and tire-road contact parameters are invaluable for enhancing the performance of vehicle control systems, such as anti-lock brake system (ABS) and electronic stability program (ESP). Today's production vehicles are equipped with onboard sensors (e.g. a 3-axis accelerometer, 3-axis gyroscope, steering wheel angle sensor, and wheel speed sensors), which when used in conjunction with certain model-based or kinematics-based observers can be used to identify relevant tire and vehicle states for optimal control of comfort, stability and handling. Vehicle state estimation is becoming ever more relevant with the increased sophistication of chassis control systems. This paper presents a comprehensive overview of the state-of-the-art in the field of vehicle and tire state estimation. It is expected to serve as a resource for researchers interested in developing vehicle state estimation algorithms for usage in advanced vehicle control and safety systems.