PATH

Transient Platoon Aerodynamics During Passing Maneuvers and In-line Oscillations

Tsuei, J. L.
Savas, O.
Hedrick, J. K.
2000

The transient aerodynamic effects in a four-vehicle platoon during passing maneuvers and in-line oscillations are investigated. A vehicle model is moved longitudinally parallel to a four-car platoon to simulate passing maneuvers. The drag and side forces experienced by each platoon member are measure using strain gauge balances. The resulting data are presented as dimensionless coefficients. It is show that each car in the platoon experiences a repulsive side force when the passing vehicle is in the neighborhood of its rear half. The side force reverses its direction and becomes an...

Feasibility Study Of Advanced Technology Hov Systems: Volume 2a: Feasibility Of Implementing Roadway Powered Electric Vehicle Technology In El Monte Busway: A Case Study

Chira-Chavala, Ted
Lechner, Edward H.
Empey, Dan M.
1992

This study investigates issues concerning the implementation and impacts of lateral guidance/control systems and the phased implementation of these systems in exclusive-access High Occupancy Vehicle (HOV) lanes. The study is divided into 5 volumes. The objectives of each volume are as follows: Vol. 1: identify strategies for early deployment of longitudinal control technologies on the highway, and to evaluate potential impacts of these strategies on traffic operation, highway capacity, and traffic accidents. Vol. 2A: assess the feasibility of early deployment of Roadway Powered Electric...

Loop Detector Data Collection and Travel Time Measurement in the Berkeley Highway Laboratory

May, Adolf D.
Cayford, Randall
Coifman, Ben
Merritt, Greg
2003

This document is the final report for the 2001-2002 Berkeley Highway Laboratory (BHL) Project which is a part of the University of California's PATH program and supported by the California Department of Transportation (Catrans). The primary objective of this project has been to maintain, improve, and conduct research on the Berkeley Highway Laboratory (BHL) detector system. This report contains ten chapters that describe the work undertaken and the results of each task of the project. The first chapter introduces the project, provides a project background, and a site description. The next...

Develop Methods to Reduce or Prevent Backing Crashes

Cooper, Douglas L.
Duffy, Sarah
Orrick, Phyllis
Ragland, David R.
2010

Workplace motor vehicle incidents at Caltrans are a significant cause of injuries, employee lost time, and property damage. Because backing crashes are major contributors to motor vehicle incidents, identifying and promoting methods of reducing backing accidents is a top priority. According to internal Caltrans’ data, 92.3% of workplace backing crashes were preventable by the driver. Backing crashes are the single largest category of preventable crashes, representing 30% of preventable crashes in the Caltrans fleet. From 1998 through 2007, preventable backing crashes cost Caltrans at least...

Modeling the Santa Monica Freeway Corridor: Simulation Experiments

Skabardonis, Alexander
2002

The report describes the findings of a study to develop a simulation testbed for the Santa Monica freeway corridor. The study created one of the largest freeway corridor networks coded for the CORSIM microscopic simulation model. The coded network consists of about 10 miles of I-10 freeway and a surface street network with 75 signalized intersections. The results from the simulation experiments indicate that several CORSIM model parameters need to be adjusted in order to accurately simulate freeway facilities for California conditions. The calibrated CORSIM model produced reasonable and...

Longitudinal Control Development For Ivhs Fully Automated And Semi-automated Systems - Phase 1

Hedrick, J. K.
Mcmahnon, D.
Swaroop, D.
Garg, V.
Gerdes, J.
Maciuca, D.
Blackman, T.
Yip, P.
1995

This report addresses some of the important longitudinal vehicle modeling and control issues of Advanced Vehicle Control Systems (AVCS) such as brake dynamic model development and validation, decentralized longitudinal control algorithms which guarantee the stability of the entire platoon and fault detection and isolation in the longitudinal vehicle dynamics of controlled vehicles.

Development of BRT Architecture: A System Engineering Approach

Hickman, Mark
Tan, Chin-Woo
Lau, Peter
Zhang, Wei-Bin
2006

This report discusses the development of system architecture for Intelligent Transportation Systems (ITS) applications for Bus Rapid Transit (BRT) systems. In the course of the development of system architecture, it is critical to take a system engineering approach in the development of BRT architecture to assess BRT service needs (or features), the functional realization of these service needs and the means of technological implementation. Motivated by the National ITS architecture, the BRT architecture has a hierarchy of three layers: application, physical, and logical. The application...

Travlnfo Field Operational Test Evaluation: Target Study Final Results

Koo, Ronald
Yim, Youngbin
2000

This paper presents the final results of the Target Study conducted for the evaluation of the Travinfo Field Operational Test. Four waves of telephone surveys were conducted in 1997 and 1998 among commuters shortly after major incidents on a selected corridor. The case study corridor is a 16 mile segment of US 101 serving major cities between San Francisco and San Jose.The commuter surveys were aimed at an understanding of travel behavior when major incidents occur. The results of the surveys suggest that traveler behavior is not greatly affected by individual incidents causing delays of...

Longitudinal And Lateral Throughput On An Idealized Highway

Hall, Randolph W.
1993

The objective of this paper is to develop a throughput model of a multiple- lane Automated Highway System (AHS) with lane changes. The paper uses deterministic approximations to model highway throughput, accounting for both longitudinal and lateral requirements. The model is designed to account for trip-length distributions, and the effect of these distributions on the rate of lane changes between each pair of adjacent lanes. To illustrate fundamental principles, the model is applied to an idealized highway operating under sanitary conditions, both in time and space. Parametric analysis is...

Summary of Observations on July 1993 Study Tour to Japan

Orne, Donald E.
Shladover, Steven E.
1993

The purpose of this report is to document some lessons learned during the July 3-16, 1993 tour of Japan and Intelligent Vehicles ’93 Symposium attendance by PATH Director Donald E. Orne and Deputy Director/AVCS Program Manager Steven E. Shladover.The tour was arranged by PATH through Japanese contacts to coincide with the Intelligent Vehicles ’93 conference. Most of the contacts were known to PATH either from introductions at various conferences or by visits to PATH offices.Special attention was given by Orne and Shladover to consider the extent to which interaction with government,...