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1.
The development of self-driving cars or autonomous vehicles has progressed at an unanticipated pace. Ironically, the driver or the driver-vehicle interaction is a largely neglected factor in the development of enabling technologies for autonomous vehicles. Therefore, this paper discusses the advantages and challenges faced by aging drivers with reference to in-vehicle technology for self-driving cars, on the basis of findings of recent studies. We summarize age-related characteristics of sensory, motor, and cognitive functions on the basis of extensive age-related research, which can provide a familiar to better aging drivers. Furthermore, we discuss some key aspects that need to be considered, such as familar to learnability, acceptance, and net effectiveness of new in-vehicle technology, as addressed in relevant studies. In addition, we present research-based examples on aging drivers and advanced technology, including a holistic approach that is being developed by MIT AgeLab, advanced navigation systems, and health monitoring systems. This paper anticipates many questions that may arise owing to the interaction of autonomous technologies with an older driver population. We expect the results of our study to be a foundation for further developments toward the consideration of needs of aging drivers while designing self-driving vehicles.  相似文献   

2.
SUMMARY

There are many problems that face transportation systems as the twenty-first century approaches, and many solutions will be required. Mass transportation systems are one large area of research that will provide some solutions. This paper presents another possible solution at the other end of the spectrum, small relatively tall and narrow tilting commuter vehicles for individual transportation. A historical overview of the various types of tilting vehicles built or proposed over the last forty years is shown and the results of these studies are discussed. If one considers a relatively tall and narrow vehicle, (under 1.0 meters or 40“ wide), to maintain high speed performance in cornering it becomes necessary to bank the vehicle into a corner to prevent overturning. The design of a modem active tilting suspension and control law for a small narrow, one-half width, commuter vehicles is presented. Analysis of the static and dynamic tipping limits illustrates which vehicles are considered tall and narrow requiring active tilting. The performance of such vehicles as they enter a steady corner is considered and how tilt dynamics may feel to passengers is discussed.  相似文献   

3.
为满足铁路客运、公路客运、城市轨道交通、公交车、出租车、社会车辆等多种交通运输方式为一体的"无缝"、"连续"、"零换乘"的要求,该文以南京交通主枢纽南站的南京汽车客运南站建设为实例,通过对场站建设、综合管理和信息化服务系统建设,以及管理组织机构建设的阐述,介绍了汽车客运南站的组成和建设,为实现现代综合运输体系创造了条件。  相似文献   

4.
获取营运车辆的时空大数据,识别车辆运行区间、车辆运营时长、车辆运行车速等关键参数,对于深入挖掘车辆位置的空间、时间分布特征具有重要意义.在分析卫星定位系统的数据特点及相关定位技术的基础上,从计算机、地理学以及交通科学3个不同领域,对位置时空数据及其特点展开了比较分析.以典型营运车辆数据——基于出租车轨迹的出行分布研究以及联网联控"两客一危"分析为例,对基于卫星定位系统的典型营运车辆时空特征分析的理论、方法及关键技术进行综述.   相似文献   

5.
无人驾驶汽车是目前汽车发展的一个大方向,无人驾驶的实现依靠于汽车的感知、决策和控制功能。路径规划属于决策中重要的一环。目前,无人驾驶汽车的路径规划算法存在受环境影响较大,无法适用于复杂的道路环境的问题,基于此文章对无人驾驶汽车轨迹规划算法进行归纳。其在广义上可分成全局路径规划和局部路径规划两种,文章对上述两种规划进行细分并介绍了各种路径规划方法的原理,分析了各个方法的优劣,为无人驾驶汽车路径规划算法的研究提供参考。  相似文献   

6.
ABSTRACT

Measuring the roll angle of single-track vehicles has always been a challenging task; however, accurate and reliable measurements of this magnitude are paramount for controlling the stability of these vehicles, both for autonomous riding and for safety reasons. A roll angle estimation is also useful in other situations, such as tests to perform the identification of the parameters of the rider control. In this work, a new algorithm is presented for estimating the roll angle of bicycles. This estimator, based on the well-known Kalman filter, employs a wheel speed sensor to approximate the speed of the vehicle, and three angular rate sensors, which are currently small and affordable sensors. The proposed method was implemented in a microcontroller and tested in a bicycle and the results were compared with measurements obtained with optical sensors, showing a good correlation. Although it has not been tested in motorcycles, comparable results are expected.  相似文献   

7.
结合我国政府全面深化改革与交通运输行业建设"四个交通"的要求,重点分析了中心城市出租汽车行业未来发展的趋势,研究提出了新形势下中心城市出租汽车的行业定位及中心城市出租汽车管理方式转变的要求;重点提出了管理目标转变、管理思路转变以及管理机制创新的建议,为国家层面有关城市出租汽车管理立法工作提供决策支持与参考,为地方政府及交通运输部门从根本上破解行业发展的深层次矛盾提供思路方法.  相似文献   

8.
SUMMARY

The technical state-of-the-art of aerodynamics of ground transportation vehicles is reviewed. Currently available theoretical calculation methods and experimental simulation techniques as well as typical results illustrating the impact of aerodynamics on vehicle performance and running characteristics are summarized and the interactions between vehicle system dynamics and aerodynamics are adressed. Correlation of theoretical and experimental data show the present potential of vehicle aerodynamics and point to fields in which further research work is necessary.  相似文献   

9.
In March 2018, an Uber-pedestrian crash and a Tesla's Model X crash attracted a lot of media attention because the vehicles were operating under self-driving and autopilot mode respectively at the time of the crash. This study aims to conduct before-and-after sentiment analysis to examine how these two fatal crashes have affected people's perceptions of self-driving and autonomous vehicle technology using Twitter data. Five different and relevant keywords were used to extract tweets. Over 1.7 million tweets were found within 15 days before and after the incidents with the specific keywords, which were eventually analyzed in this study. The results indicate that after the two incidents, the negative tweets on “self-driving/autonomous” technology increased by 32 percentage points (from 14% to 46%). The compound scores of “pedestrian crash”, “Uber”, and “Tesla” keywords saw a 6% decrease while “self-driving/autonomous” recorded the highest change with an 11% decrease. Before the Uber-incident, 19% of the tweets on Uber were negative and 27% were positive. With the Uber-pedestrian crash, these percentages have changed to 30% negative and 23% positive. Overall, the negativity in the tweets and the percentage of negative tweets on self-driving/autonomous technology have increased after their involvement in fatal crashes. Providing opportunities to interact with this developing technology has shown to positively influence peoples' perception.  相似文献   

10.
城市出租车交通分布预测模型   总被引:4,自引:0,他引:4  
王昊  王炜  陈峻  徐任婷 《公路交通科技》2006,23(6):145-148,156
现有交通需求预测方法以居民出行分析为基础,预测得出的出租车交通分布量实质上是载客出租车的交通分布量,因此其预测值比实际值偏小.基于出租车的运行规律,提出了出租车出行概念,将系统中出租车总出行量分解为载客出租车出行量和空驶出租车出行量,并运用Logit概率选择模型,建立了载客出租车出行量与空驶出租车出行量之间的关系,从而得出了总体出租车的交通分布预测方法.该方法既可以模拟城市现状的出租车交通分布状况,也可以对规划年出租车的交通分布进行预测,避免了传统分析方法对空驶出租车交通量的疏漏.  相似文献   

11.
SUMMARY

The transportation of ore can be made more cost efficient by use of bigger and heavier trains. An increase in axle load is thereby wanted. The fleet of ore wagons of today at Malmbanan/Ofotbanan in northern Sweden and Norway has to be updated. It is of interest to find out if it is possible to allow a higher axle load on the track with new wagons

To be able to understand and predict the effects on track wear depending on what type of vehicle that is in use, the contact forces between wheels and rails have to be determined. A computer aided analysis has been made of the dynamic behaviour of three test vehicles equipped with different types of three-piece bogies running at Malmbanan. The vehicles are modelled and their interaction with the track is analysed using the multibody simulation package GENSYS

The simulations show that, even if the axle load is increased from 25 tons to 30 tons and the velocity is increased from 50 km/h to 60 km/h, it is possible to reduce lateral track forces and wear in curves by using a different bogie than the standard three-piece bogie used today.  相似文献   

12.
针对目前主流自动驾驶整车测试方法及ADAS整车在环仿真测试方法的特点。利用虚拟现实和实时仿真技术,搭建自动驾驶整车在环仿真平台,并在室内进行仿真平台的模拟实现和案例测试。该平台不仅可以提供丰富的测试环境,危险场景以及难复现的复杂场景进行可重复性测试,而且使用的是真实车辆的车辆动力学特性,无需复杂的车辆动力学模型,同时测试成本也相对低廉。  相似文献   

13.
SUMMARY

As a result of extensive research and development in several countries, the technologies of magnetic suspension and linear electric drives are becoming available for transportation applications. The successful demonstration and operation of prototype vehicles has established the technical viability of these systems. Several urban transit or shuttle services, with magnetic suspension and/or linear motor propulsion are likely to be operational within 3-4 years. After the final stages ofdevelopment and rigorous testing, high speed systems are likely to be an option for intercity implementation by the end of the decade. This paper presents a report on the worldwide status of R&D and test programs of non-contact suspension and propulsion technology for guided ground transport.  相似文献   

14.
近年来“网约车”数量越来越多,“网约车”等待时间长与载客热区需求大等问题也逐步显现,乘车体验亟需改善。在成都市出租车GPS数据的基础上,研究出租车出行分布规律,划分工作日为早、晚、夜高峰相关时段,引入k-距离曲线改进DBSCAN空间聚类算法,对出租车上下客点进行聚类分析,并用数据挖掘得出载客热区。采用BP神经网络预测载客热区的出行需求,预测结果表明,早高峰时段BP神经网络模型的MAPE分别较随机森林模型、岭回归模型提高了3.25%和5.87%,晚高峰时段提高了2.98%和4.32%、夜高峰时段提高了1.44%和2.58%,验证了BP神经网络在出租车需求预测方面的可行性。   相似文献   

15.
城市出租车需求来源于社会活动的需要,深圳特区外出租车的需求受到该地区经济发展水平、人口数量、土地规模、运输价格等多种因素的影响。文中介绍了城市出租车类比分析的原理和方法,并建立了城市出租车类比分析预测模型,通过运用类比城市实际的数据,预测了深圳市特区外出租车的目前和远景需求量。  相似文献   

16.
SUMMARY

In spite of considerable interest in active controls for a wide variety of road and rail vehicles comparatively little work has been carried out on the dynamics of actively guided vehicles in which steering is carried out in response to signals from a controller seeking to follow a given path or track. Drawing from the relevant fields of guided rubber tyred vehicles, rail vehicles and mobile robots the common basis of the dynamics of active guidance is discussed,and this simple theoretical framework is then followed by a review of work in this field. Attention is restricted to wheeled vehicles.  相似文献   

17.
在绿色交通的条件下,以层次分析法对拉萨市居民公共交通出行的影响因素进行分析,得到居民公共交通出行主要影响因素是经济性和环保意识,其次为便捷性和个人偏好以及出行者的年龄。提出以提高经济性和增强环保意识为主,兼顾便捷性和个人偏好以及年龄为辅的公共交通出行引导策略。  相似文献   

18.
SUMMARY

Active control systems offer significant functional advantages over passive systems; their introduction into production-line vehicles, however, is cautious and slow. This survey describes the recent progress in the analysis, design and technology of active controls in vehicles. It includes the state-of-the-art of their introduction into operation as well as their future potential in view of recent advances in technology and computer aided design strategies. The survey has been limited to suspensions for vehicles on roads and tracks.  相似文献   

19.
Abstract

Researchers have collected extensive vehicle activity data in Beijing using GPS and attempted to develop a comprehensive database of facility- and speed-specific operating mode (OpMode) distributions of various vehicle types for estimating on-road vehicle emissions. This study developed the specific OpMode distributions of light duty vehicles (LDVs) for both restricted access and unrestricted access road types at various average speeds for characteristic analysis. (1) Strong patterns are found in the variations in OpMode distributions with the increase in the average speed: the time fraction of Decelerating/Braking remains less than 7%. The fraction of Idling decreases dramatically from 95% to 0%, while the fraction of Cruising/Accelerating increases from 2% to 94%. The fraction of Coasting increases to 28% and then decreases. (2) The time fractions for restricted access and unrestricted access are significantly different at the same average speeds, especially in Operating Modes #0, #1, #11, #12, #13, #14, #21, and #22, possibly causing an error of 20% in the emissions estimations. (3) Taxis show different OpMode distributions than those for private cars in the operating modes of Decelerating/Braking, Idling, and high-VSP modes, especially at low average speeds. The differences are derived from the more skillful driving behaviors of taxi drivers and may cause an estimation error of over 10%. Thus, the activities of taxis and private cars should be modeled separately for on-road emissions estimations.  相似文献   

20.
网络信息社会我国城市居民出行特征研究   总被引:3,自引:0,他引:3  
从出行的总量、目的、方式等角度分析了信息社会城市居民出行特征的改变,为我国未来城市交通规划的居民出行研究做一些新的尝试。  相似文献   

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