Data

Video-Based Vehicle Signature Analysis and Tracking Phase 1: Verification of Concept Preliminary Testing

MacCarley, Arthur C.
1998

This report describes the results of the PATH/Caltrans-funded project Video-Base Signature Analysis and Tracking (VSAT) System, Phase 1: Verification of Concept and Preliminary Testing. The VSAT System was conceived in 1995 by Loragen Systems, of Glendale, California, as a means for non-intrusively tracking individual vehicles on freeways for data collection purposes. The concept involves the use of a computer vision methods to make simple measurements of external dimensions, points of optical demarcation, and predominant colors of each vehicle. A conventional color video camera serves as...

Estimation of Truck Traffic Volume from Single Loop Detectors Using Lane-to-Lane Speed Correlation

Kwon, Jaimyoung
Varaiya, Pravin
Skabardonis, Alexander
2003

An algorithm for real time estimation of truck traffic in multi-lane freeway is proposed. The algorithm uses data from single loop detectors-the most widely installed surveillance technology for urban freeways in the US. The algorithm works for those freeway locations that have a truck-free lane, and exhibit high lane-to-lane speed correlation. These conditions are met by most urban freeway locations. The algorithm produces real time estimates of the truck traffic volumes at the location. It can also be used to produce alternative estimate of the mean effective vehicle length, which can...

Transient Aerodynamics in Vehicle Interactions: Data Base Summary

Chen, A.L.
Hedrick, K.
Savas, O.
1998

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.Since a lane change (either leaving or joining a platoon)...

Berkeley Highway Lab Videl Data Collection System

Chen, Chao
Lyddy, Daniel
Dundar, Baris
2004

The goal of this project is to replace the existing analog video collection system on the roof of Pacific Park Plaza (PPP) with a digital one. This video collection system is part of the Berkeley Highway Laboratory (BHL) testbed. It records video of traffic on a continuous one-kilometer section of Interstate 80 (I-80) near Emeryville, CA. This section of I-80 features on-ramps, off-ramps, and weaving zones. The video of interactions between vehicles can be fed to a machine-vision system, which generates vehicle trajectories to be used in a variety of traffic studies. The video itself can...

Simulation Modeling Of The Santa Monica Freeway

Bloomberg, Loren D.
May, Adolf D.
1994

As part of a project investigating the benefits of Intelligent Vehicle Highway Systems (IVHS) technology using simulation, two models of the Santa Monica Freeway in Los Angeles were developed. This report describes the work performed to create, test, and apply these simulations. Two independent simulations were coded, using FREQ and INTEGRATION models, from the available data. The report describes the strategies, limitations, and assumptions needed to code the Santa Monica Freeway using the two simulation tools. After coding the models, calibrating the output to match traffic performance...

Orange County Transit/traffic Management Integration And Traveler Information Project: Evaluation Plan

Hall, R.
Hickman, M.
1996

This document focuses on a Field Operational Test (FOT) to develop an integrated information system for transit and traffic management and for traveler information that relies on Global Positioning System (GPS) equipped buses as probe vehicles. The document provides the evaluation plan for the FOT. The plan covers three principal elements: 1) Institutional, TMC Operator and Bus Operator, 2) Public Knowledge and Perceptions, and 3) System performance. The document provides an overall evaluation framework that describes how the evaluation elements will assess project objectives. In addition...

An Enhancement to Speed Estimation with Single Loops

Lin, Wei-Hua
Dahlgren, Joy
Huo, Hong
2003

Traffic data from single loop detectors are one of the dominant data sources widely used in many traffic operation centers and traveler information systems. Speed estimation from single loop detectors is mainly based on occupancy data, a conversion factor from occupancy to density (which is related to vehicle length), and the assumed relationship between flow, speed, and density. This paper investigates the discrepancy between the speed estimated with single loops and the speed measured directly from double loops. It was found that the inaccuracy of speed estimation with single loops is...

Modernization of Center-to-Center Data Communication Standards: Gap Analysis Technical Memorandum

Peterson, Brian
2021

This document provides a gap analysis based on three previous technical memorandums delivered as part of this project, including a review of the Traffic Management Data Dictionary (TMDD) standard, a review of current and future transportation needs, and a review of the state of the art in technology and systems development. The intention of this document is to provide a review of this standard for transmission of data between traffic management centers (TMCs), with explicit commentary on usability of the standard with specific examples based on its implementation in the Caltrans I-210...

TravInfo Evaluation Plan: Update 1

Yim, Youngbin
Khattak, Asad
Miller, Mark
Hall, Randolph
Weissenberger, Stein
1994

TravInfo is a public/private partnership formed to provide wide-spread dissemination of real-time information on transportation conditions and travel options. A fundamental premise is that a public surveillance and database system, designed to open-architecture standards, will be an effective stimulus for private sector innovations in ATIS (Advanced Traveler Information Systems) technologies and, ultimately, their deployment.TravInfo is a Field Operational Test of a centralized database providing easy access to real-time travel information on all modes of transportation in the Bay Area....

Visualizing Loop Detector Data

Zhang, Xiaoyan
Rice, John
1999

Over the years, many TMCs have accumulated large loop detector datasets due to the loops' extensive presence in existing infrastructure. However, the information in these data sets often lies dormant partly because of the lack of effective means to summarize and display it. We present a simple visualization technique developed for loop detector data which addresses this issue. The method uses color-encoded images to visualize loop detector measurements as a function of space and time. We use examples based on a field dataset to illustrate some of its possible applications.