PATH

Effect of Longitudinal Control on Capacity

Beji, Yousser
1987

This paper focuses on what benefits a longitudinal control system can be expected to render to the present highway system.There are three major reasons why longitudinal control should be expected to improve traffic flow and to reduce accidents.(1) It may permit higher traffic densities with uniform spacing forming an even distribution with increased travel speeds and consequently higher capacity.(2) It may reduce the rate of rear-end collisions that occur on urban freeways.(3) It can provide increased stability in traffic flow (shockwaves due to human response characteristics are the main...

PATH ATMIS State of the Research Annual Report Fiscal Year 1998 / 1999

Tam, Robert
1999

This report summarizes PATH ATMIS and Systems research for fiscal year 1998/1999. In each of the brief project descriptions we state the objectives of the project and outline its status and some of its principal results. These descriptions are not intended to be comprehensive or complete, but rather to present a picture of the main thrusts of each of the reported projects. References are provided in the end of the report for more detailed information about particular projects. Taken together, the collection of project descriptions should also give a reader an overview of the entire program...

TMDD Standards Update Recommendations – Data Structures

Peterson, Brian
2023

This document provides a set of recommendations for modernization of the Traffic Management Data Dictionary (TMDD) (1), currently at version 3.1. These recommendations are based upon the following: Connected Corridors project experience; three previous technical memorandums provided under this project discussing the current and future state of transportation, the state of the supporting technology for information exchange, and a review of the TMDD standard; a gap analysis based on the three technical memorandums delivered as part of this project. The intention of this document is to inform...

Lateral Control Of Commuter Buses

Hingwe, Pushkar
Tomizuka, Masayoshi
1995

This report presents two approaches to the design of the lateral controllers for commuter buses based on Sliding Mode Control (SMC). The objective of the control is to track the lane centerline. The first controller uses the sensor output which is a combination of yaw and lateral error. The second controller achieves tracking objective by providing a yaw rate to the vehicle so as to keep the lateral error dynamics stable. The two controllers are compared by performing simulations for a range of parameters.

Traveler Response to New Dynamic Information Sources: Analyzing Corridor and Area-Wide Behavioral Surveys

Yim, Youngbin
Khattak, Asad J.
Raw, Jeremey
2004

Intelligent Transportation Systems present a well-known innovation opportunity to address urban congestion and allow greater access to transportation networks. New sources of travel information are emerging rapidly and they are likely to significantly impact traveler decisions and transportation network performance. To assess the value and impact of these new sources, this paper develops a comprehensive conceptual model based on information processing and traveler response. Specifically, the model accounts for the effect of information source, content and quality on information access and...

Evaluation Methods for Measuring the Value of ITS Services and Benefits from Implementation: Part X Freeway Service Patrols

Levinson, David
Parthasarathi, Pavithra Kandadai
2001

The goal of our report is to determine the value that people place on the benefits offered by freeway service patrols in comparison to private assistance services and how much they would be willing to pay to avoid being stranded when their vehicle breaks down on the freeway. The report investigates the factors that contribute to people choosing to rely on the highway assistance services in comparison to the private assistance services. The studies conducted so far have focused on the effectiveness of the freeway service patrol whereas this report analyzes the factors that influence people...

Video-based Vehicle Signature Analysis and Tracking System Phase 2: Algorithm Development and Preliminary Testing

MacCarley, Arthur C.
2001

This report describes the results of the PATH/Caltrans-funded project Video-Base Signature Analysis and Tracking (V2SAT) System, Phase 2 Algorithm Development and Preliminary Testing. The V2SATSystem was conceived in 1995 by Loragen Systems, of San Luis Obispo, California, as a means for non-intrusively tracking individual vehicles on freeways for data collection purposes. The concept involves the use of computer vision methods to make simple optical measurements on digitized real-time images of each vehicle on the freeway. A conventional color video camera serves as the primary sensor....

Incident Management with Advanced Traveller Information Systems

Al-Deek, Haitham
Kanafani, Adib
1991

Advanced Traveller Information Systems (ATIS) can be used to collect and disseminate dynamic information about travel times on highway links. One of the potential uses of these systems is to manage incidents. The objective of this research is to showunder what incident conditions is it relevant to provide real time traffic information to travellers.A model that uses graphical queueing techniques is utilized to define cases when ATIS is beneficial and cases when it is not, and to evaluate its benefits as measured by travel time savings. The model is applied to a simple road network with two...

An Economic Analysis Of Network Deployment And Application To Road Pricing

Levinson, David
1998

This paper develops an economic framework for developing strategies necessary to deploy networks, and applies the framework to the deployment of road pricing. The cost structure of highways are discussed. A graphical method for measuring welfare with road pricing is presented. The relationship of space and financing mechanism is reviewed. A network model of the economy is presented. This is followed by a discussion of network externalities, and how those relate to both the deployment and emergence of technologies. Finally, the deployment of three main elements relating to road pricing: use...

Single-channel IVHS Communication Architecture

Linnartz, Jean-paul M. G.
1994

This report documents a single-channel architecture offering two-way communication between vehicles and a fixed communication infrastructure. Part I discusses the technical advantages and disadvantages of a dedicated Intelligent Vehicle Highway Systems (IVHS) communications infrastructure versus the use of a hybrid system involving several existing communication networks. Aspects such as spectrum efficiency, message capacity, and network performance are described. Part II proposes a network architecture that offers several transmission services essential to IVHS communications, using only...