PATH

Transportation Modeling for the Environment

Barth, Matthew J.
Norbeck, Joseph M.
1994

In this report, the authors describe preliminary research dealing with vehicle emissions associated directly with 1) Automated Highway Systems ( AHS) and 2) ramp metering. In performing this analysis, a power-demand modal emissions model has been integrated with several transportation simulation models in order to quantitatively determine the effects of Intelligent Transportation Systems (ITS) technology on vehicle emissions. For AHS, a steady-state speed/emissions comparison has been conducted between vehicles that are platooned and non-platooned. A comparison has been made between a...

Transitional Platoon Maneuvers in an Automated Highway System

Hedrick, J. K.
Narendran, V. K.
Chang, K. S.
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...

Transient Vehicle Aerodynamics in Four-Car Platoons

Chen, A. L.
Savas, Omer
Hedrick, Karl
1997

The vehicles in a platoon will experience transient aerodynamic forces as vehicles leave and join the platoon at various locations. A platoon of scale vehicle models is placed in a wind tunnel and measurements are made of the transient forces and moments as one of the vehicles is moved into and out of the platoon. The results from the wind tunnel experiments will allow the computer vehicle control algorithms to better predict the transient aerodynamics the vehicles in the platoon will encounter during leaving and joining maneuvers. \par Since a lane change (either leaving or joining a...

Estimating Pedestrian Accident Exposure

Greene-Roesel, Ryan
Diogenes, Mara Chagas
Ragland, David D.
2010

We are pleased to present the final report of Caltrans Task Orders 5211 and 6211, “Estimating Pedestrian Accident Exposure.” The project focused on defining pedestrian exposure and evaluating methods for measuring it within the State of California. The project was funded by the California Department of Transportation as part of the California Partners for Advanced Transit and Highways (PATH) Program of the University of California.Deliverables associated with the project include (I) a protocol report on assessing pedestrian exposure, which is accompanied by a training curriculum and an...

Traffic Surveillance and Detection Technology Development: New Traffic Sensor Technology Final Report

Malik, Jitendra
Russell, Stuart
1997

This document presents the final report on a project focusing on new traffic sensor technology, mainly video cameras, for traffic surveillance and detection. It describes a Transportation Management Center (TMC), designed for the collation and computation of multi-site statistics. The report discusses the following elements: tracking approach, motion-based grouping, tracking and grouping procedures, vehicle classification, hardware port, parameters computed at the TMC, testing methodology, and test results.

Evaluation of the Transit Information System in Southern California

Le Colletter, Emmanuel
Yim, Youngbin
Hall, Randolph
1993

This report presents a study of the effectiveness of the transit telephone information system on trip behavior at Metropolitan Transit Authority ( MTA), from both the user's and the operator's perspective. The objectives of the experiment were: 1) to assess the perception of dynamic transit information service, 2) to identify the media which can most effectively disseminate transit information, and 3) to compare the information service by human operators with the service by an automated system. The study looks at both the supply and the demand side of the provision of telephone information...

Traffic Modeling to Evaluate Potential Benefits of Advanced Traffic Management and In-Vehicle Information Systems in a Freeway/Arterial Corridor

Gardes, Yonnel
1990

This study includes a literature review of existing traffic simulation models potentially suited for evaluating advanced traffic control strategies and in-vehicle information systems within an integrated freeway/ arterial corridor. Chapter 1 presents a literature review and identification of candidate models. Chapter 2 contains a preliminary screening of candidate models. Chapter 3 presents an in-depth evaluation of short list of models. And, Chapter 4 gives conclusions of the research and recommendations for future directions.

Traffic Management Systems Performance Measurement: Study Directions and Scope, Proposed Measures of Effectiveness, and Proposed Action Priorities

Banks, James H.
Kelly, Gregory
1997

This report documents research focusing on: 1) analyzing performance measurements for California Department of Transportation (Caltrans) Transportation Management Centers (TMCs); 2) identifying and assessing the feasibility of data collection and management activities required to support TMC performance measurement; and, 3) recommending specific actions by Caltrans and the California PATH program that will facilitate performance measurement.

A Decision-Oriented Framework for Evaluating Deployment Strategies for Intelligent Transportation Systems

Tsao, Jacob H.-S.
1999

Because Intelligent Transportation Systems (ITS) R&D is performed for the ultimate deployment in the real world, deployment issues may limit design options for ITS concepts and technologies and, hence, can be viewed as constraints on ITS R&D. Therefore, ITS deployment issues must be studied at the outset of the R&D process. This paper develops a framework to help recognize and organize such issues. The findings can be used by ITS researchers in developing deployable ITS concepts and technologies and by ITS promoters in deploying ITS technologies having been...

Traffic Flow Control in Automated Highway Systems

Alvarez, Luis
Horowitz, Roberto
1997

This report studies the problem of traffic control in the Automated Highway System (AHS) hierarchical architecture of the California PATH program. A link layer controller for the PATH AHS architecture is presented. It is shown that the proposed control laws stabilize the vehicular density and flow around predetermined profiles.