Data

Evaluation of Portable Automated Data Collection Technologies: Final Report

Bank, James H.
2008

Portable automated traffic data collection systems were evaluated by means of a series of field demonstrations. Systems demonstrated included (a) temporarily mounted microwave radar sensors intended to provide volume, speed, and/or length classification data for traffic census or various traffic studies; (b) similar sensors mounted on a semi-permanent basis and intended to serve as substitutes for loop detectors in traffic surveillance systems; and (c) low-mounted infrared sensors used for axle counting. The field demonstrations focused on the issues of sensor accuracy for all systems and...

Cooperative Adaptive Cruise Control (CACC) For Partially Automated Truck Platooning:Final Report

Tan, Yaolong
Kanellakopoulos, Ioannis
2002

The report describes the results of the project funded under MOU 314.The main result is the experimental implementation of various longitudinal control algorithms that were developed under MOU124 and MOU 240. In order to conduct these experiments, in collaboration with Professor Tomizuka’s group and PATH Personnel, we first outfitted a Class-8 tractor-trailer commercial heavy-duty vehicle on loan from Freightliner Corporation with the necessary sensors and actuators for fully automated operation. These sensors and actuators included the vehicle speed sensors, air-brake pressure sensors,...

Streamlining Connected Automated Vehicle Test Data Collection and Evaluation in the Hardware-in-the-Loop Environment

Fu, Zhe
Liu, Hao, PhD
Lu, Xiao-Yun, PhD
2020

Quality data collection, processing, and analysis are foundational to good research, policy making and regulation development. With the rapid development of Connected Automated Vehicles (CAV) technologies, it is urgent for both researchers and policy makers to obtain and evaluate good quality CAV data to better understand CAV impacts. CAV hardware-in-the-loop (HIL) tests can expedite CAV performance evaluation and system implementation. This research aims at equipping an existing HIL test tool with data management functions. To this end, a database instance on MySQL has been integrated...

Tools for Operations Planning (TOPL2)

Varaiya, Pravin
2009

TOPL is a suite of tools to specify operational improvements including ramp metering, incident and demand management, auxiliary lanes, traveler information, and to quickly estimate the benefits that such improvements can realize. TOPL is based on the macroscopic cell transmission model (CTM). Advances under TOPL2 can be classified under (1) theory, (2) software and algorithms, and (3) applications.In terms of theory, the CTM model for a freeway was thoroughly analyzed and extended to arterials. In software, the major advance was the development of Aurora—an object-oriented simulation...

Optimal Use of Changeable Message Signs for Displaying Travel Times

Ban, Xuegang (Jeff)
Li, Yuwei
Margulici, Jean-Davi
2009

The report describes the research performed and the findings of the PATH Task Order 6303 “Optimal Use of Changeable Message Signs for Displaying Travel Times”. First, travel time estimation methods from various sources are evaluated against probe vehicle data. Next, a survey of San Francisco Bay Area commuters was undertaken regarding the perception and preference for displaying travel times on CMS. Finally, a model that evaluates the CMS impacts on network traffic and determines optimal CMS configurations was developed and tested. Deployment guidelines for CMS are presented based on these...

Planning the Development of a Commercial Motor Vehicle Virtual Weigh Station Technology Testbed

Miller, Mark A.
Sharafsaleh, Ashkan
2010

This report describes the issues associated with planning the development of a technology testbed for Virtual Weigh Stations in California. These issues may be organized into the following categories: system design and architecture, operational environment, siting & location, data collection, functional requirements and options, technology requirements and options, identification  of  stakeholders,  operational  testing  and  evaluation  (operational  scenarios,  performance measures, benefits &amp...

Vehicle To Roadside Communications Study

Polydoros, Andreas
Dessouky, Khaled
Pereira, Jorge M. N.
Sun, Chung-ming
Lee, Kuo-chun
Papavassiliou, Thomas D.
Li, Victor O. K.
1993

The objective of this study is to address the communication system design issues of Intelligent Vehicle Highway Systems (IVHS). The focus of Phase I of this research is the design for California Advanced Driver Information Systems (CADIS). The emphasis is on the architecture and topology aspects of the physical link and access layers connecting the moving layers with the fixed infrastructure. The work is divided into the following categories: Automatic Vehicle Identification (AVI), IVHS communications survey and functional requirements, modeling of IVHS fading channels, multiple-access...

Cartesius and CTNET Integration and Field Operational Test

Rindt, Craig R.
McNally, Michael G.
2009

This report describes the results of PATH Task Order 5324—the first year of a multi-year project to integrate the Cartesius incident management system with Cal-trans CTNET traffic signal management system. The results of this research are a set of software requirements for reimplementing the Cartesius to interoperate with CTNET. An analysis of the existing Cartesius prototype explains how the need to focus the system on deployment and technical shortcomings of the existing system justifies a reimplementation of the software. From here, we describe the problem to be solved by the new...

Analysis Toward Mitigation of Congestion and Conflicts at Light Rail Grade Crossings and Intersections

Li, Meng
Wu, Guoyuan
Johnston, Scott
Zhang, Wei-Bin
2009

Although many different railroad grade crossing control products are available, the most challenging limitation to traditional grade crossing systems is their inability to deliver consistent warning times in response to varying train speeds and station stops (particularly nearside stops). As a result, rail-roadway crossings often generate conflicts and congestion for motorist traffic and sometimes delay trains.By conducting system level analysis, this project will investigate the interactions and conflicts between urban/suburban rail and cross traffic. The information that is obtained will...

Real-time Density Estimation on Freeway with Loop Detector and Probe Data

Qiu, Tony Z.
Lu, Xiao-Yun
Chow, Andy H. F.
Shladover, Steven
2009

Density, speed and flow are the three critical parameters for traffic analysis. Traffic management and control with high performance require accurate estimation/prediction of distance mean speed and density for large spatial and temporal coverage. Speed, including time mean speed and distance mean speed, and flow estimation are relatively easy to be measured and estimated in the practical site, but accurate density estimation is very difficult. Inductive loop detector systems have been widely deployed, it makes better sense to fully adopt available infrastructure to achieve required...