Environment

Alternative Traffic Signal Illumination

Cohn, Theodore E.
Greenhouse, Daniel
Knowles, Richard
1998

New technologies have enabled the production of traffic signals that have significant advantages over standard incandescent signals, including greater energy efficiency and lower maintenance costs. Before the new signals are installed in the field, it is important to assure that they as visible as the older signals. We have developed a quality index we term the usability factor (UF) which can be used to evaluate the visibility of a new device relative to that of a standard reference lamp. We have measured UF's of a variety of new types of lamps by means of heterochromatic flicker...

Development and Performance Evaluation of AVCSS Deployment Sequences to Advance from Today's Driving Environment to Full Automation

Shladover, Steven
VanderWerf, Joel
Miller, Mark A.
Kourjanskaia, Natalia
Krishnan, Hariharan
2001

This report presents the findings of its investigation into deployment sequences to better understand the paths that could be taken from today's driving environment to vehicle-highway automation. One of the most vexing problems has always been that of determining how to advance from the present-day manually-controlled vehicles to the future fully automated vehicles. Considerable research attention has been devoted to defining the architecture and operating protocols, as well as the technology, of automated highway systems. Rather less attention has been devoted to defining the steps by...

Using Cooperative Adaptive Cruise Control (CACC) to Form High-Performance Vehicle Streams:Simulation Results Analysis

Liu, Hao
Kan, Xingan (David)
Shladover, Steven E.
Lu, Xiao-Yun
2018

This document contains detailed simulation results analysis and discussion for the Federal Highway Administration (FHWA) Exploratory Advanced Research (EAR) project entitled Using Cooperative Adaptive Cruise Control (CACC) to Form High-Performance Vehicle Streams. The objective of this study is to obtain authoritative predictions of traffic impacts of ACC and CACC at various market penetrations and define the CACC operation strategies that create the most capacity and throughput improvement in the freeway traffic stream. A microscopic traffic simulation environment has been developed for...

Simulation Of IVHS On The Smart Corridor Using The Integration Model: Phase 1: Initial Investigations

Gardes, Yonnel
May, Adolf D.
1993

The general objective of this project is to evaluate the potential benefits of Advanced Traveler Information Systems and Advanced Traffic Management Systems on the Smart Corridor. This report describes Phase 1 of the project in which the INTEGRATION traffic simulation model is used to help simulate ATIS and ATMS on a freeway/arterial environment.

Intelligent Sensor Validation And Fusion For Vehicle Guidance Using Probabilistic And Fuzzy Methods

Agogino, Alice
Goebel, Kai
Alag, Sanam
1997

This study reports on a method to accomplish sensor validation and fusion in Intelligent Transportation Systems (ITS). The method is based on probabilistic and fuzzy techniques that express a confidence in the sensor data and take into account environmental factors and the state of the system. Sensor data fusion uses the confidence assigned to each sensor reading and integrates them into one reading. Noise and failure are filtered from the data and lead to a safety improvement in ITS.

PEDAMACS: Power Efficient and Delay Aware Medium Access Protocol for Sensor Networks

Coleri, Sinem
Varaiya, Pravin
2004

We consider a class of sensor networks with two special characteristics. First, the nodes periodically generate data for transfer to a distinguished node called the access point. Second, the nodes are (transmit) power and energy limited, but the access point, which communicates with the ‘outside world’, is not so limited. Such networks might be used for instance when a geographically distributed physical process, such as traffic on a freeway or at an urban street intersection, is periodically sensed for purposes of process control. We propose a medium access control scheme, called PEDAMACS...

A Planning Methodology For Intelligent Urban Transportation Systems

Kanafani, Adib
Khattak, Asad
Crotty, Melanie
Dahlgren, Joy
1992

This report deals with an introduction to the control aspect of platoon maneuvers in Automated Highway Systems. The different platoon maneuvers include lane changes, merge procedures and split procedures. The first part of the report consists of a review of the existing literature in this area. The survey is split up into the quasi-synchronous and vehicle follower controller methods of approach to the problem. The subsequent sections deal with the mathematical description of the problem with two representations of the system under study, varying only in level of model complexity. The...

Cooperative Multiple-Sensor Fusion for Automated Vehicle Control

Hedrick, J. K.
Jang, J.
Potier, A.
2004

The number and quality of sensors available for both on-board vehicle and infrastructure-based sensing is increasing while the cost of these sensors is rapidly decreasing. On-board vehicle sensors can be utilized for both individual vehicle safety as well as automated vehicle control. It is becoming imperative that "fusion" techniques be developed, i.e., methods to combine the wide variety of sensors available so that reliable and accurate information can be obtained even though individual sensors may fail or become extremely noisy. The process of sensor fusion combines multiple sensor...

Planning the Development of a Commercial Motor Vehicle Virtual Weigh Station Technology Testbed

Miller, Mark A.
Sharafsaleh, Ashkan
2010

This report describes the issues associated with planning the development of a technology testbed for Virtual Weigh Stations in California. These issues may be organized into the following categories: system design and architecture, operational environment, siting & location, data collection, functional requirements and options, technology requirements and options, identification  of  stakeholders,  operational  testing  and  evaluation  (operational  scenarios,  performance measures, benefits &amp...

Vehicle To Roadside Communications Study

Polydoros, Andreas
Dessouky, Khaled
Pereira, Jorge M. N.
Sun, Chung-ming
Lee, Kuo-chun
Papavassiliou, Thomas D.
Li, Victor O. K.
1993

The objective of this study is to address the communication system design issues of Intelligent Vehicle Highway Systems (IVHS). The focus of Phase I of this research is the design for California Advanced Driver Information Systems (CADIS). The emphasis is on the architecture and topology aspects of the physical link and access layers connecting the moving layers with the fixed infrastructure. The work is divided into the following categories: Automatic Vehicle Identification (AVI), IVHS communications survey and functional requirements, modeling of IVHS fading channels, multiple-access...