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After the turn of the century, growing social attention has been paid to environmental concerns, especially the reduction of greenhouse gas emissions and it comes down to a personal daily life concern which will affect the purchasing decision of vehicles in the future. Among all the sources of greenhouse gas emissions, the transportation industry is the primary target of reduction and almost every automotive company pours unprecedented amounts of money to reengineer the vehicle technologies for better fuel efficiency and reduced CO2 emission. Besides those efforts paid for sheer improvements of genuine vehicle technologies, NISSAN testified that “connectivity” with outside servers contributed a lot to reduce fuel consumption, thus the less emission of GHG, with two major factors; 1. detouring the traffic congestions with the support of probe-based real-time traffic information and 2. providing Eco-driving advices for the better driving behavior to prompt the better usage of energy.

In contrast to highway, there are some sections not well maintained in urban roads. In these sections, there may be faint lane marks or static obstacles due to construction or some other reasons. Therefore, an automated vehicle following system such as traffic jam assistant should consider these sections to guarantee the safety of the system. In order to achieve this purpose, a model predictive control (MPC) scheme has been developed. The objectives of MPC are to compute the sequence of optimal steering input for vehicle following with obstacle avoidance. For this, the MPC uses the lead vehicle's state and obstacle's position obtained by lidars. For this purpose, a simplified nonlinear model of the vehicle was used to predict the future evolution of the system. Based on this prediction, performance index is optimized under operating constraints at each time step. A test vehicle equipped with two lidars on left and right corner of the front bumper has been developed.

Collision avoidance systems for rear-end collisions have been researched and developed. It is necessary to activate collision warnings and automatic braking systems with appropriate timing determined by a monitoring system of a driver's braking action. Although there are various systems to monitor driving behavior, this study aims to create a monitoring system using a driver model. This study was intended to construct a model of a driver's braking action with the Time Delay Neural Network (TDNN). An experimental scenario focuses on rear-end collisions on a highway, such as the driver of a host vehicle controlling the brake to avoid a collision into a leading vehicle in a stationary condition caused by a traffic jam. In order to examine the accuracy of the TDNN model, this study used four parameters: the number of learning, the number of neurons in the hidden layer, the sampling time with 0.01 second as a minimum value, and the number of the delay time.

The article proves the necessity for heating the air in the pneumatic engine of a hybrid power unit designed for moving a compact wheeled vehicle. The aim is to improve the pneumatic engine operation indicators by heating the compressed air before it is supplied to the cylinder using the obtained theoretical and experimental studies. For the easy-to-use of assessing the effectiveness of heating the air supplied to a pneumatic engine, the experiments were carried out by two pressure ps = 0.7 MPa and ps = 0.9 MPa, according to them the testing of a pneumatic unit was conducted without heating the compressed air at the temperature equal to the ambient temperature Ts = 293 K. Also, during the experiments a pneumatic engine was tested at other temperatures while supplying the compressed air at the inlet to the engine cylinder.

Electronic Stop-Start (ESS) system automatically stops and restarts the engine to save energy, improve fuel economy and reduce emissions when the vehicle is stationary during traffic lights, traffic jams etc. The stop and start events cause unwanted vibrations at the seat track which induce discomfort to the driver and passengers in the vehicle. These events are very short duration events, usually taking less than a second. Time domain analysis can help in simulating this event but it is difficult to see modal interactions and root cause issues. Modal transient analysis also poses a limitation on defining frequency dependent stiffness and damping for multiple mounts. This leads to inaccuracy in capturing mount behavior at different frequencies. Most efficient way to simulate this event would be by frequency response analysis using modal superposition method.

Traffic congestions are increasingly severe in urban areas, especially at the merging areas of the ramps and the arterial roads. Because of the complex conflict relationship of the vehicles in ramps and arterial roads in terms of time-spatial constraints, it is challenging to coordinate the motion of these vehicles, which may easily cause congestions at the merging areas. The connected and automated vehicles (CAVs) provides potential opportunities to solve this problem. A centralized merging control method for CAVs is proposed in this paper, which can organize the traffic movements in merging areas efficiently and safely. In this method, the merging control model is built to formulate the vehicle coordination problem in merging areas, which is then transformed to the discrete nonlinear optimization form. A simulation model is built to verify the proposed method.

The continuing growth of urban population centers has led to increased traffic congestion for which vehicles can spend considerable periods at low speed/low load and idle conditions. For light-duty diesel vehicles, these low load conditions are characterized by low engine exhaust temperatures (~100oC). Exhaust temperatures can be too low to maintain the activity of the catalytic exhaust aftertreatment devices (usually need >~200oC) which can lead to high emissions that contribute to deteriorating urban air quality. This study is a follow-on to two previous studies on the effects of throttling, post-injection, and cylinder deactivation (CDA) on light-duty diesel engine exhaust temperatures and emissions. The focus of the present study is on fuel consumption, exhaust temperatures, and emissions with and without cylinder deactivation or with fuel cutout, and the sensitivity to or effects of fuel rail pressure, along with observations of apparent idle engine friction.

In the past two decades, rapidly expanding economy in China led to burst in travel demand and pursuit of quality of life. It further promoted the rapid growth of China's passenger car market. China had already become the largest vehicle sales country, exceeding the U.S. in 2010. By the end of 2018, there had been over 240 million cars in China, with over 200 million passenger cars. The surge of car ownership has also brought a series of problems, like traffic congestion, long commuting time, insufficient parking space, etc. Therefore, some local governments in China introduced vehicle purchase restriction policies to control the growth and gross of vehicle stock. Different cities issued different rules. Lottery and auction mechanisms both exist. There are also differences in classification and licensing of electric vehicles. However, with the recent slowdown of economic development, China's car sales began to decline in 2018, and the trend of 2019 is also not optimistic.

This SAE Standard provides a table of textual messages meeting the requirements for expressing “Radio Data Systems” (RDS) phrases commonly used in the ITS industry. They can be used both over the RDS subcarrier transmission media as part of a 37-bit long “Group 8a message” as well as being used to provide a common content list of phrases used in a wide number of other media and applications. This document SHALL define the normative index values to be used, extending the CEN established list to provide phrases needed by US practitioners. This standard provides non-normative textual phrases which MAY be used by implementers to ensure intelligible results. This document SHALL follow the formats and rules established in SAE J2540 in the expressions, manipulations, and use of such tables. It should be pointed out that within the rules established by this document a variety of final table are all considered “compliant” with the document, and may vary as fits the needs of implementers.

This paper presents a method for reliability assessment of the electric grid with distributed generation providing support to the system. Evaluation of customer controlled distributed generation contribution is done for two cases; the first case analyses distributed generation wherein generation units export power to the grid. The second case analyses onsite generation wherein units handle loads at individual customer sites, thus relieving grid congestion. Reliability parameters for the distributed generation systems were obtained from data collected from existing systems that have been in operation for an extended period of time. Calculations are performed on the IEEE-Reliability Test System. The state duration sampling approach using Monte Carlo simulations is employed to evaluate the ability of the system to meet demand requirements. The impact of distributed generation on the utility controlled grid as well as on individual customer reliability is evaluated.

The United States Department of Transportation (USDOT) and the Crash Avoidance Metrics Partnership-Vehicle Safety Communications 2 (CAMP-VSC2) Consortium (Ford, General Motors, Honda, Mercedes-Benz, and Toyota) initiated, in December 2006, a three-year collaborative effort in the area of wireless-based safety applications under the Vehicle Safety Communications-Applications (VSC-A) Project. The VSC-A Project developed and tested Vehicle-to-Vehicle (V2V) communications-based safety systems to determine if Dedicated Short Range Communications (DSRC) at 5.9 GHz, in combination with vehicle positioning, would improve upon autonomous vehicle-based safety systems and/or enable new communications-based safety applications.

“Zero Emission Vehicles” in the form of pure electric vehicles are quite feasible and useful for limited cruising ranges. However, market success depends on customer acceptance. Studies show, that customers expect electric vehicles with driving performance similar to conventional vehicles while comparable cruising ranges should be available at low additional cost. With currently available batteries using lithium ion technology a gravimetric energy density of only one percent of the energy density of gasoline or diesel can be reached. With respect to acceptable additional costs this effect leads to significant reduction of the cruising range. For various reasons such as battery aging, demand for heating, traffic jams, etc., this already decreased cruising range is further reduced. In such cases electrical energy can be generated with a demand oriented (down-) sized combustion engine, a so called “Range Extender”.

Electric vehicles are seen as a key driver to address the issue of global warming, mainly through their zero tailpipe emissions operation and energy efficiency improvements. However, this does not solve the problem of urban chaos, related to traffic congestion and parking space cluttering, which contribute to increase human stress and overall economic productivity decrease. To address all these issues, electric urban buses come as an obvious solution, and they also have the advantages of being quieter than regular buses and of promoting a better travel experience to passengers. Nowadays there are already electric buses operating in some parts of the world and one of the main concerns is their high weight, which is mainly due to the amount of batteries they carry in order to have an adequate range.

The legislative and market pressure for CO2 reduction and fuel efficient powertrains lead to a variety of automatic transmission concepts in recent years. The CVT technology, the dual clutch technology (DCT) and optimized architectures of torque converter / planetary gear based automatic transmissions (AT), such as 6, 7, and 8 speed ATs entered the market in the last decade. Also different hybrid technologies have entered the market offering further improvement for fuel consumption especially in city driving. Helpful for OEMs and suppliers to flexibly meet market demands proofed the use of modular hybrid solutions. Clear demand to meet were packages of existing vehicles and powertrains with AT and hybrid transmission (HT), e.g. the modular transmission kit based on the ZF 8 speed AT. Hybrid technology is offering fuel efficiency benefits, but there are also reasons for a slow market penetration.

Motor vehicles play an indispensable role in the modern society as a means of individual transportation. For higher safety and efficiency in the automotive transportation, integrated automotive information systems are now under vigorous research and development in major countries of the world. In the United Sates, a lot of governmental and nongovernmental private projects are under way under the coordination by the IVHS (Intelligent Vehicle Highway System) which is an advisory organ to the DOT. Meanwhile in Europe, major programs are actively promoted including the program PROMETHEUS (Programme for a European Traffic with Highest Efficiency and Unprecedented Safety) which is a part of the nongovernmental project EUREKA (European Research Coordination Agency), and the government-led project DRIVE (Dedicated Road Infrastructure for Vehicle Safety in Europe).

Many questions surround the possible implementation of an advanced driver information system into passenger vehicles. The technology to relieve increasing traffic congestion problems exists today, but the methods to safely use this technology do not. There are many concerns in the government, industry, and academic communities surrounding the implementation of graphic display monitors inside passenger vehicles. This concern stems from recent studies on the effect of cellular phones, touch panels, and electronic navigational systems on driver attention demands. These studies show that driver attention is taken from the roadway to operate these systems. However, more research into basic human/vehicle ergonomics needs to be conducted in order to determine how the demands of in-vehicle electronics affect highway safety.

Awareness of possible forthcoming bad weather conditions (fog, snow or heavy rain) as well as traffic potentially dangerous situations (car accidents or traffic jam) can be vital to the driver specially in today heavy traffic congested environment. A short/medium range realy warning, system improving efficiency and safety of driving is described. The system we call Hand Shake consists in an intervehicular short range radio link which automatically creates an interchange of information among the vehicles. A vision enhancement systems is as well described. It consists of a remote pulse intensified camera associated to a pulse lighting method of the scenery. The first one reduce the damping effect in the light propagation though fog and the second one reduce the backscattering effect due to fog. Both system which can usefully complement radar systems are under evaluation on FIAT and show promising results.

Traffic congestion has become a major problem in the United States. Advanced technologies, referred to as Intelligent Vehicle/Highway Systems (IVHS), offer the best solution. IVHS allow communication between vehicle and highway. IVHS include Advanced Traffic Management Systems, Advanced Driver Information Systems, Commercial Vehicle Operations, and Automated Vehicle Control Systems. IVHS offer to reduce congestion, enhance safety, increase productivity, and improve U.S. competitiveness. IVHS development programs are underway in Europe and Japan. No national IVHS program exists in the United States. Three questions are asked. Is there need for a national IVHS program? Which system is intelligent, the vehicle or the highway? Which system comes first, the vehicle or the highway? Public and private sector cooperation is needed. The federal government will coordinate efforts between state and local governments and private industry.

The decade of the nineties represents a unique time. Traffic congestion, petroleum shortages and health and environmental concerns resulting from fuel spills, smog and greenhouse effects are converging to force changes in the gasoline powered automobile. This presentation recognizes these circumstances as it presents the program and initial results from a flexible fueled ride-share van demonstration project. The ride-share vans are 1990 Plymouth Voyagers with two different powertrains: a 2.5 liter normally aspirated engine and a 2.2 liter turbo-charged engine. The 2.5 L fuel flexible engine has electronic spark and fuel management so that it can operate on any combination from 0 to 85% methanol (M85) and gasoline. The 2.2 L gasoline tolerant engine has electronic turbo-boost management as well as electronic spark and fuel control. The power boost increases with percentage of methanol and its associated octane enhancement.

The paper will include a brief overview of the Pathfinder system which has been installed in Los Angeles. The system is undergoing evaluation at this time. Some implementation experiences will be included. For example, the paper will discuss some of the reasons for the changes from the presentation of congestion information in synthesized voice to all digital voice. The Pathfinder experience with mixtures of digital and synthesized speech led to confusion, which can be avoided in other systems. The time taken for message presentation was excessive and led to a necessary reduction in the number of messages presented when the voice mode is selected by the driver. This significant limitation could alter the design of other systems which might rely on speech as a presentation mode to the driver.