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TravInfo is a two-year test of advanced traveler information systems for the San Francisco Bay Area. TravInfo's hub for data collection, processing, and dissemination of timely and accurate traveler information to both the public and private sectors is the Traveler Information Center. The operation and performance of the Traveler Information Center provides the basis for subsequent potential benefits to both the public and private sectors. Data is accessed by the public sector through the Traveler Advisory Telephone System, a telephone hotline, and by the private sector via modems through the Landline Data System. Human operators of the Traveler Information Center play a crucial role in its performance and subsequent delivery of potential benefits.

Various freeway segments in metropolitan Detroit are currently equipped with an advanced traffic management and information system (ATMIS). The ATMIS is expected to have improved the performance of the Detroit metropolitan transportation system. This improvement, however, has been difficult to quantify due to the absence of pre-ATMIS data. This paper presents the experimental plan and expected outcomes for an ongoing study examining the effectiveness of the existing ATMIS within an 8 by 5 km section of the M-10 (Lodge) Freeway corridor in Detroit, Michigan. The experimental plan proposes to quantify, through simulation, the impacts of the existing ATMIS and to estimate the benefit of ATMIS components' integration and enhancement.

The benefits of advanced traveler information systems (ATIS) to travelers are likely to be significant. ATIS enables travelers to make informed travel decisions, which may result in changes in travel behavior, thus permitting efficient use of the existing roadway infrastructure. This paper presents the summary findings of three travel behavior studies conducted in the San Francisco Bay Area regarding the benefits of ATIS from the traveler perspective. The surveys revealed that the perceived benefits of traveler information varied somewhat depending on the types of information received. Information received through a traveler advisory telephone system called TravInfo had greater impact on travel behavior than did radio traffic information because it offers up-to-the minute and route-specific information.

The successful implementation of Automated Vehicle Control Systems (AVCS) depends on the reachable private and public benefits. Therefore, the profitability of the system has to be proven. The traditional assessment tool for both is the cost-benefit analysis. The paper presents a general methodological framework, which allows using the cost-benefit analyses for all kinds of AVC-systems. Main focus lies on the assessment of benefits. Therefore, a traffic simulation model is introduced that enables the direct calculation of benefits coming from the traffic effects of an AVC-system. As an example, a cost-benefit analysis is undertaken for the CHAUFFEUR-system.

At the ‘Institut fuer Kraftfahrwesen Aachen, ika’ (Institute of Automotive Engineering, Technical University Aachen, Germany) the submicroscopic traffic simulation program PELOPS (Program for the dEvelopment of Longitudinal micrOscopic traffic Processes in a Systemrelevant environment) was developed in co-operation with the BMW AG (1). PELOPS is oriented towards the fundamental elements of traffic, namely route and environment, driver and vehicle. The focal point of latest research with PELOPS was the investigation of optimizing measures through the application of new vehicle- and traffic-technologies. Effects on driving-comfort, driving safety, traffic efficiency as well as fuel consumption and emissions are simulated and assessed in urban traffic, various traffic situations on German highways and synthetic testing-procedures. The paper gives information about the simulation techniques and the results of the current analysis.

Intelligent Transportation Systems (ITS) require reliable location information with emphasis being put on sensor level integration and low power consumption. The Global Positioning System (GPS) has been proposed as a potential technology to provide this information but has been hampered by poor performance (in urban environments) and power hungry board level solutions. Increased pressure on in-vehicle sensor power consumption has driven SiRF Technology Inc. to develop the SiRFstar1/LX GPS chip set (GSP1LX and GRF1LX). This improved chip set architecture enables lower power consumption without sacrificing tracking or navigation performance specifically in difficult urban canyons. Most GPS systems have been designed as stand-alone board level solutions that can be used in high-level system integration.

The objective of this paper is to describe the development of the Multi-Lane Traffic Monitoring System (MTMS), a family of laser-based [1], low-cost, non-intrusive, lane monitoring systems used to measure and classify vehicular traffic over multiple lane roadways. The non-intrusive nature permits portable or permanent setup off the roadway without presenting hazardous situations to highway personnel, motorists, or costly construction, maintenance, and traffic disruptions. Several models are being developed to facilitate remote monitoring, data storage, and Global Positioning System (GPS) tagging. The data presented in this paper include preliminary design attributes such as LADAR, processing algorithms, user programmable control interface, and prototype performance specifications.

This paper describes an advanced vehicle radar system operating at a frequency of 60.5 GHz that has been jointly developed for the Japanese automobile and truck market by Eaton VORAD Technologies of San Diego, California, and Hitachi, Ltd. of Japan. The radar system is used for both collision warning system (CWS) applications and for adaptive cruise control (ACC) applications. The radar system employs monopulse radar technology to measure azimuth angle to each vehicle in the forward direction. The techniques used to reduce cost and complexity of monopulse radar for low cost use on commercial vehicles are described. These techniques combine Doppler radar technology with digitally derived monopulse processing. Japan is the only country that has selected the frequency band of 60 GHz for vehicle radar systems. The reasons for this selection are discussed and the advantages and disadvantages of this frequency band are presented.

The development from passive safety systems to driver assistance systems is discussed in this paper. One example of a driver assistance system is the so-called autonomous cruise control system. In this paper, the Automatic Distance contRol system (ADR) will be described in detail. Both the benefits for the customer as well as the technical aspects of the system are discussed. Basically, a five beam laser sensor is used to detect objects. Electric throttle control and electric brake control is ensuring that the safety distance between vehicles is kept up to a specific level.

Analyzing how man translates motion intentions to an object creates a requirement for a universal multi-axis force measurement device. The concept is based on the premise that to control the trajectory of a moving object we exert a force on that object, or on a surrogate device that represents the coordinate system of the objects trajectory. The following paper presents the design and the underlining technology of a universal multi axis force sensor (encompassing the surrogate coordinate system) through which we can control the trajectory of an object positioned with electro-mechanical actuators.

The advance in research and development will make the deployment of automated vehicles a reality in the near future. At the initial stage, semi-automated vehicles with the capability to follow each other automatically in the same lane will coexist with manually driven vehicles on the same roadway system. A number of safety and human factor issues need to be resolved before such mixing becomes possible. In this paper we analyze the effect of mixing on capacity and stability of vehicle following. We found that capacity may not always increase with the percentage of semi-automated vehicles because the intervehicle spacing has to account for driver reaction times during stopping. Semi-automated vehicles will attenuate the “slinky effects” without affecting the total travel time.

Since 1989 the Automotive Engineering Department of Darmstadt University of Technology (fzd) has carried out measurements of tire tread deformations through the use of sensors which are integrated into the tire. With these tire sensors fzd has achieved the possibility to qualitatively and quantitatively measure forces acting on the tire, especially local slip effects, which are the basis for friction detection. To investigate local slip fzd designed a completely new measuring device. Utilization of available tire/road friction and local slip events were measured in a specially equipped test car. This paper describes the Darmstadt Tire Sensor, the theoretical vehicle system, the methods to study tire sensor behaviour as well as the results achieved so far.

The objective of this paper is to define how complex automotive electronics have become and how advanced semiconductor technology is being developed to simplify the development of these systems. Automotive systems are becoming more complex electronically than could ever be imagined. There are now many Electronic Control Units being implemented on vehicles which are each linked to separate networks and are sharing data on high speed buses. In order to handle the increasing processing bandwidth required, and to interface effectively with the many sensors and actuators on the modern motor vehicle, significant advances are being made in semiconductor technology. The types of systems which are becoming more complex will be defined along with the reasons for becoming so. ‘System chips’ are now being developed which can integrate together different types of semiconductor technology in order to reduce chip-count, size and increase performance and reliability.

In an ITS alternatives analysis based on forecasts of travel demand in the 2020 time frame for the I-5 corridor north of downtown Seattle, researchers at Mitretek Systems modeled and quantified the impact of ITS technologies over a range of weather, incident and demand conditions. The primary ITS components modeled included incident management (IMS), adaptive and coordinated signal control (ATMS), and advanced traveler information systems (ATIS). These advanced, adaptive systems allow for quick reaction to events like incidents or surges in demand that an average-condition based analysis could not capture. Therefore, the goal of the simulation effort in this study was to examine the effectiveness of these ITS systems deployed in combination over a realistic range of variation expected in both roadway supply (incidents or weather effects) and travel demand.

Combi-Road is a container road transport system with high capacity. The system uses specially designed tracks which can be constructed as separate roads or as extra lanes alongside existing motorways. The containers are pulled on semi-trailers by unmanned automatically controlled electrical vehicles. The system allows to reduce the amount of vertical handlings in the transport chain. On so-called transfer stations containers are exchanged with sea shipping, road, railway and inland shipping. The Combi-Road project started January 1994. During the process of development the innovative technological nature of the concept has been strongly emphasized. In an early stage the implementation strategy has been paid attention to. This paper describes the basic technical details of the Combi-Road system, as well as the results of the initial test phase which has been completed by the end of 1996.

The concept of the automated highway has been around for several decades. However, even if the technology has much progressed and has been demonstrated recently in quite elaborate forms, it is still unclear how it can be deployed realistically. The manufacturers now seem to propose a very gradual approach through the introduction of driving aids such as active trajectory control (ABS and ESP), adaptive cruise control (ACC), collision warning and vigilance monitoring. Here, we take the stand that a more disruptive process can take place with fully automated vehicles deployed locally as a public transport system based on individual vehicles. These vehicles would use dedicated road tracks, more or less protected from the intrusion of other vehicles. Later in the process of deployment of these dedicated roads, they could be made available to private vehicles equipped with driving automation.

The purpose of this report is to experimentally determine the air flow through the cooling module (air-conditioning condenser plus engine radiator) of a Ford Windstar minivan when the van is operated at a fraction of a vehicle length behind a lead van. Pressures and temperatures are measured across the cooling module while the vans are in operation, and a standard calibration relates the pressure drop to the flow velocity through the cooling module. The Windstars are connected in tandem and driven on a test track at spacings of 0.22, 0.28, 0.38, 0.62, 0.88, and 1.0, expressed as fractions of the Wind-star length. For the purposes of the test, an override switch is installed to allow the close-following van to be operated either with both cooling fans remaining on or with both fans disabled. Air flow is expressed either as a volume flow, in cubic meters per second, or as the fraction of the flow for a van operating in isolation at the same forward speed.

Experimental results are reported on spray characterization of gasoline pintle injectors A and B; the former with swirl vanes while the latter without swirl vanes upstream the pintle seat. Injection system was common rail with accumulator unit injector and pressure fuel metering. Spray tip penetration length was measured by laser beam attenuation technique. Time-resolved droplet axial and radial velocity components and droplet diameter were measured at many probe positions in both axial and radial directions by a two-component phase Doppler particle analyzer (PDPA). The measurement covered detailed spray structures of both injectors under rail pressures ranged from 8 to 14 MPa and with fuel delivery from 11 to 42 mm3/inj for Injector A and from 4 to 28mm3/inj for Injector B. Correlations of droplet velocity and diameter with arrival time to the PDPA probe volume are discussed.

A multidimensional model for flows, sprays and combustion in engines is applied to study the entrainment characteristics of transient jets of relevance to Diesel and direct-injection spark-ignition engines. The following jets will be considered: solid-cone jets, hollow-cone jets and air-assist sprays. The entrainment characteristics will be evaluated by studying the evolution of lean, flammable and rich mixtures in the chamber. The focus of this work is on comparing the entrainment rates of jets from multi-hole solid-cone type jets with hollow-cone type jets. It will be shown that for the conditions considered in this work, the entrainment rate of the hollow-cone jets is less than that of the solid-cone jets. The effects of imparting swirl to the jets and to the air in the ambient will also be briefly discussed.

Two-stroke spark-ignition engines with fuel injection constitute a good alternative to four-stroke engines in meeting the demand for ever lighter-weight and higher-performance vehicle engines; they are also suitable for industrial applications if their inherent advantages of design simplicity, low cost and high specific power are maintained. In both cases, for these machines to constitute a successful alternative, emission levels must be equal to or lower than those of comparable four-stroke engines. Several studies are currently dealing with the so-called ‘new generation two-stroke engines’. In nearly all these, charge control by means of fuel injection has been proposed to overcome the well-known problems of fuel and lube-oil consumption, and the probably unacceptable level of pollutant emissions. Direct injection, in particular, seems to guarantee the best results as it allows to avoid the short-circuiting of the fuel to the exhaust.