PATH

Freeway Traffic Control Using Variable Speed Limits

Lu, Xiao-Yun
Nowakowski, Christopher
Su, Dongyan
Shladover, Steven E.
2011

The work reported here includes the development of the underlying theory for detecting traffic flow breakdown at a bottleneck and for defining the speed profiles that vehicles should be following in order to maximize the flow through the bottleneck region. It also includes a preliminary test of the communication of the variable speed limit values to an instrumented vehicle for display to drivers from the general public, in order to determine their reactions to the variable speed limits. The selection of variable speed limits (VSL) to reduce traffic breakdowns is based on careful modeling...

Models Of Vehicular Collision: Development And Simulation With Emphasis On Safety III: Computer Code Programmer's Guide And User Manual For Medusa

O'reilly, Oliver M.
Papadopoulos, P.
Lo, G.-J.
Varadi, P.C.
1998

This report presents a user's manual and a programmer's guide for the computer program MEDUSA. The program is capable of simulating the impacts of several vehicles. It assumes that the collision are elastic, and is consequently applicable for low relative velocity impacts. A theoretical background of the collision detection algorithm is first given, followed by user's manual and programmer's guide.

Analysis and Documentation of Roadway Incident Using Software and Photogrammetric Techniques

Su, Ray J.
Chan, Ching-Yao
2004

This report is a deliverable of a project, TR0002, sponsored by the California Office of Traffic Safety, contracted through California Department of Transportation, and conducted by California PATH. Roadway incidents, besides their direct impacts of property damage, injuries and fatalities, can quickly lead to further congestion or even secondary incidents of nearby traffic. Due to the direct and indirect effects of incidents and congestion afterwards, it is important that post-incident handling proceed as quickly as they can. One primary factor in the delays of incident handling is the...

Potential Payoffs From Ivhs: A Framework For Analysis

Rockwell International Science Center
1992

The purpose of this study is to provide a logical framework for the identification and evaluation of alternative Intelligent Vehicle Highway Systems (IVHS) functions, to sort by importance, and to specifically relate the various IVHS functions with the public sector goals they might serve. Toward this goal, an analytical sensitivity study was performed to estimate the benefits of those functions associated with modifying the speed-density-flow curves through the application of vehicle automation. Some analysis was also carried out to assess intersection throughput when signalization is...

Field Evaluation of San Pablo Corridor Transit Signal Priority (TSP) System

Zhou, Kun
Li, Meng
Johnston, Scott
Zhang, Wei-Bin
Sun, Sonja
Leung, Kai
Lau, James
Chiu, Paul
2008

This document reports the results of the evaluation of the Transit Signal Priority currently under operation at AC Transit. The paper discusses about the Measure of Effectiveness and a quantitative evaluation method for TSP. It reports the data collected and analysis conducted of the concerned TSP system and presented the evaluation results.

Platoon Collision Dynamics And Emergency Maneuvering II: Platoon Simulations For Small Disturbances

Tongue, Benson H.
Yang, Yean-tzong
1994

The purpose of this report is to investigate the effect of selected parameter variations on the response of a platoon. The response of a platoon under different control algorithms is also examined. A four-car platoon with prescribed lead car dynamics was used for simulations and vehicles in the platoon were assumed to be identical. Convergence studies of the numerical integration were undertaken and convergence was verified. The purpose of these simulations was to build a knowledge base with regard to nonlinear platoon responses, to be used as an initial guide in developing simpler...

San Diego I-15 Demonstration Integrated Corridor Management System: PATH Report on Stage 3: Site Demonstration and Evaluation

Dion, Francois
Skabardonis, Alexander
2015

This report describes activities surrounding the design, building, deployment, operation, and evaluation of an innovative corridor management (ICM) system aiming to improve mobility within the Interstate 15 (I-15) corridor in San Diego, California, by integrating the operations of the I-15 freeway with the surrounding arterials and transit systems. Systems engineering principles were applied to support the development of the demonstration ICM system and the systems engineering process was credited by the project team with having contributed significantly to the success of the project....

Studies Of The Adoption And Use Of Location And Communication Technologies By The Trucking Industry

Scapinakis, Dimitris A.
Garrison, William Louis
1991

Describes current and proposed investigations on the adoption and use of positioning (navigation) and communication technologies by the trucking industry.

Fuzzy Traffic Density Homogenizer For Automated Highway Systems

Chien, C. C.
Ioannou, P.
Chu, C.K.
1995

In this paper, a fuzzy traffic density homogenizer is proposed to alleviate or avoid congestion by smoothing the traffic density distribution profile over freeway lanes. The proposed fuzzy homogenizer consists of two parts: the fuzzy mean speed controller and the fuzzy on- ramp controller. Simulation results are used to demonstrate that the proposed controllers can eliminate traffic flow instabilities leading to smooth traffic flows.

Vehicle/Driver Monitoring for Enhanced Safety of Transit Buses

Shi, Mingyu
Tomizuka, Masayoshi
2007

This report documents the findings of the study “Vehicle/Driver Monitoring for Enhanced Safety of Transit Buses” conducted as part of the PATH project TO5400. The goal of study TO5400 is todesign and implementation of a reliable vehicle/driver monitoring system with aim to enhance driving safety of transit buses.The main objectives of the project are: (1) to identify a simply model that best describes the driving patterns of human drivers, and (2) to develop an algorithm which can generate warning messages when there is a provision of danger.In this study, it is assumed that the driver...