Towards connected autonomous driving: review of use-cases

Connected autonomous vehicles are considered as mitigators of issues such as traffic congestion, road safety, inefficient fuel consumption and pollutant emissions that current road transportation system suffers from. Connected autonomous vehicles utilise communication systems to enhance the performance of autonomous vehicles and consequently improve transportation by enabling cooperative functionalities, namely, cooperative sensing and cooperative manoeuvring. The former refers to the ability to share and fuse information gathered from vehicle sensors and road infrastructures to create a better understanding of the surrounding environment while the latter enables groups of vehicles to drive in a co-ordinated way which ultimately results in a safer and more efficient driving environment. However, there is a gap in understanding how and to what extent connectivity can contribute to improving the efficiency, safety and performance of autonomous vehicles. Therefore, the aim of this paper is to investigate the potential benefits that can be achieved from connected autonomous vehicles through analysing five use-cases: (i) vehicle platooning, (ii) lane changing, (iii) intersection management, (iv) energy management and (v) road friction estimation. The current paper highlights that although connectivity can enhance the performance of autonomous vehicles and contribute to the improvement of current transportation system performance, the level of achievable benefits depends on factors such as the penetration rate of connected vehicles, traffic scenarios and the way of augmenting off-board information into vehicle control systems.     

基于道路特征信息变化率的公路线形质量评价

公路线形质量对行车的舒适性和安全性有着非常重要的影响，如何合理有效地对其进行评价是一个有待解决的问题。从驾驶员行车时接受道路信息的角度出发，提出了道路特征信息变化率的概念，并作为评价公路线形质量的定量指标运用到平面线形、纵断面线形和平纵组合的评价研究中。研究表明：平曲线半径越小，驾驶员接受的道路特性信息变化率越大，驾驶员负担也越重；此外，平曲线长度、竖曲线半径及平纵组合都对道路特性信息变化率有较大的影响。研究成果可为改善公路线形，提高行车安全提供依据。     

柴油机高速电磁阀驱动特性仿真分析

为了降低电磁阀的功率损耗,确保其长期可靠运转,基于HEUI喷油器,利用Matlab软件对电磁阀PWM控制方式进行了仿真分析。仿真结果表明,提高线圈电压有助于实现电磁阀快速开启,开启脉冲和PWM占空比决定了不同阶段电流的大小,PWM脉冲频率影响电流的稳定性,几方面的有机调节,可以实现先高后低理想的电流波形。仿真结果为电磁阀的柔性控制提供了可靠依据。     

Hilbert-Huang变换结合近似熵在疲劳驾驶时脑电分析中的应用

研究疲劳驾驶状态下驾驶员脑电信号的特征。结合Hilbert-Huang Transform(HHT)方法和近似熵方法,提出了一种新的脑电信号处理方法:HHT近似熵方法,首先用HHT方法把脑电信号分解为多个内在的模式分量,然后求取各个模式分量的近似熵值,探讨疲劳驾驶时脑电信号的非线性特征。在汽车模拟驾驶仪上进行疲劳驾驶,同时用脑电测量仪器测量驾驶员脑电,用HHT近似熵方法对正常静坐、正常驾驶、疲劳静坐、疲劳驾驶4种脑电信号进行具体的分析处理,结果表明d_2、d_4近似熵比值可以区分4种脑电信号,可以作为疲劳驾驶时的脑电特征。为疲劳驾驶的预警系统研究提供了理论上的一些依据和参考。     

汽车电动滑门设计研讨

汽车电动滑门(PSD)系统是在滑门系统的基础上,集成电子智能控制技术和传感器防夹技术的高级滑门系统,广泛应用于高档豪华商务车,兼具了滑门侧开启方便性和人机智能控制性,越来越受到消费者的青睐。本文结合江淮M6项目,介绍了汽车电动滑门的各子系统构成和原理,实现了电动滑门系统的自主开发。     

基于驾驶特性的超车模型研究

超车行驶作为驾驶人行车过程中重要的行为之一,与行驶安全性有着直接的联系。为建立符合驾驶人操作习惯的超车模型,本文通过实车试验采集不同驾驶人在高速公路的超车行驶数据,并以此采用多项式回归拟合建立基于驾驶人操作特性的超车模型,最后利用prescan软件对提出的超车模型进行了仿真分析,结果表明建立的超车模型能够真实地反映驾驶人超车过程中的操作习惯,为超车行为的研究提供了可靠的理论依据。     

Using on-board logging devices to study the longer-term impact of an eco-driving course

In this paper the long-term impact of an eco-driving training course is evaluated by monitoring driving behavior and fuel consumption for several months before and after the course. Cars were equipped with an on-board logging device that records the position and speed of the vehicle using GPS tracking as well as real time as electronic engine data extracted from the controller area network. The data includes mileage, number of revolutions per minute, position of the accelerator pedal, and instantaneous fuel consumption. It was gathered over a period of 10 months for 10 drivers during real-life conditions thus enabling an individual drive style analysis. The average fuel consumption four months after the course fell by 5.8%. Most drivers showed an immediate improvement in fuel consumption that was stable over time, but some tended to fall back into their original driving habits.     

Suburban attitudes toward policies aimed at reducing solo driving

Policies that are aimed at discouraging commuters from solo driving have become a part of overall efforts to improve air quality and reduce traffic congestion. Since driving alone is the overwhelming choice of employed residents in US metropolitan areas, the political acceptability of proposed policy changes plays a role in their success. The 1992 Orange County (CA) Annual Survey asked employed solo drivers to rate their likelihood of changing from solo driving in response to various fees and incentives. Fewer say they would be very likely to stop solo driving if they were charged a parking fee at work (20%), a smog fee (17%) or a congestion fee (16%), than if their employers paid them a cash bonus for stopping solo driving (28%), or if more public transit (33%) or more carpools at work (35%) were available. Young and lower-status solo drivers are more likely than others to say they would stop driving alone if there were fees or cash bonuses. Current non-solo drivers tend to be young and low income, providing a validity check on the demographic predictors of stated preferences. The findings are discussed in light of recent policy changes in Southern California.     

新的轮式驱动电动车电子差速控制算法的研究

提出了一种用于轮式驱动电动车的电子差速控制算法,将转弯时转矩分配计算和基于车轮滑移率的开关控制相结合,对车辆左右驱动轮输入不同的转矩,同时根据轮胎偏转角的变化率确定目标滑移率。仿真研究证明,与采用机械差速器相比,新的电子差速控制系统鲁棒性好,车辆的驾驶更安全平稳,并能获得更优异的转向性能和更快的响应特性。     

汽车底盘测功机辅助驾驶装置的设计及其系统仿真

针对汽车底盘测功机进行试验时的人为误差因素,提出了辅助驾驶装置的设计方案及其模糊控制策略,并利用MATLAB/SIMULINK工具进行仿真。