Roads/Highways

Initial Scoping of Bay Area Smart Mobility Corridors and ITS World Congress

Shaheen, Susan
Finson, Rachel S.
McCormick, Cynthia
2004

The Innovative Corridors Initiative (ICI) is a multi-year project designed to encourage the early deployment of innovative technologies for Intelligent Transportation Systems (ITS) in California. ITS technologies are defined through a broad array of information and vehicle control technologies that are designed to improve traffic and transit management including safety, user choice, congestion, and incident response. For over a decade, ITS technologies have been gaining acceptance and are now utilized in every major metropolitan area in the United States to enhance transportation system...

Predictability of Time-Dependent Traffic Backups and Other Reproducible Traits in Experimental Highway Data

Smilowitz, Karen
Daganzo, Carlos
1999

Traffic data from a 4-mile long congested rural road in Orinda, California, are used to show that traffic delays and vehicle accumulations between any two generic observers located inside a road section can be predicted from the traffic counts measured at the extremes of the section. The traffic model does not require "recalibration" on the day of the experiment, and works well despite what appears to be location-specific driver behavior.

Vehicle Reidentification and Travel Measurements on Congested Freeways

Coifman, Benjamin
1999

This paper presents a vehicle reidentification algorithm for consecutive detector stations on a freeway, whereby a vehicle measurement made at a downstream detector station is matched with the vehicle's corresponding measurement at an upstream station. The method is illustrated using measured vehicle lengths from paired loop detector speed traps. Where speed traps are quite common, often placed at half mile spacings or less on urban freeways. In conventional operation, these detectors only monitor traffic conditions over the loops, leaving most of the freeway unmonitored. By taking the...

Collecting Road Traffic Data Using ALOHA Mobile Radio Channel

Linnartz, Jean-Paul M.G.
Gamba, David P.
1993

This report proposes a spectrum efficientsolution for transmitting link travel times from vehicles to a central infrastructure. The performance of an ALOHA mobile radio system for this application is studied analytically. The average number of new updates per minute and the expected time lapsed since the latest update of the road traffic situation in a particular street section is obtained. Results show that in an urban environment, a single (cellular) radio channel has sufficient capacity if receivers are located every 5 to 10 km.

Multi-Sensor Traffic Data Fusion

Kim, ZuWhan
Skabardonis, A.
2003

This report describes unique surveillance system on a section of I-80 freeway in the city of Emeryville. The system, called the Berkeley Highway Laboratory (BHL), consists of eight dual loop detector stations along the freeway section, and 12 video cameras. Advanced machine vision algorithms were developed to process the video data to generate vehicle trajectories. Efforts are underway to fuse the loop and video detector data to obtain detailed and accurate information on traffic operating conditions

Inter Vehicle Spacing: User's Manual (2 Diskettes Included)

Ioannou, P.
Kanaris, A.
Grammagnat, A.
1997

This documentation and software provides a tool which enable a user to perform the following tasks regarding vehicle spacing:; calculate the minimum initial spacing between two vehicles, calculate the possibility and severity of collision between two vehicles, visualize the motion of the two vehicles in the longitudinal direction during braking maneuvers, and calculate the highway capacity given factors for velocity, spacing, and size of vehicles and platoons.

TravInfo Field Operational Test Institutional Evaluation Final Results

Yim, Youngbin
Deakin, Elizabeth
2000

This paper documents the final analysis of a three part series of institutional evaluations of the TravInfo Field Operational Test from its inception in 1992 through its completion in 1998. The Field Operational Test was performed over a two-year period from September 1996 to September 1998. Funding for the TravInfo evaluation was from the Federal Highway Administration with a matching grant from the California Department of Transportation (Caltrans). The institutional evaluation examined TravInfo's unique concept of open-architecture and its collaborative public-private partnership to...

The Spatial Evolution of Traffic Under the Two Wave Speed Assumption: A Shortcut Procedure and Some Observations

Daganzo, Carlos F.
1993

This paper describes the behavior of traffic in a homogeneous highway according to the hydrodynamic theory, in the special casewhere the flow-density relationship is triangular; i.e. when only two wave velocities exist. It presents an exact formula thatpredicts the vehicle that would be found at position x at time t, given the locations of all the vehicles at time zero. The formula, which does not require identification of the vehicle positions at intermediate times, automatically accounts for the creation and dissipation of any shocks. It can be used to calculate system performance...

DYN-OPT Users Manual

Caliskan, C.
Hall, R.W.
1997

This document is a users manual for DYN-OPT, a linear program that optimally and dynamically assigns traffic to lanes on an automated highway. The program maximizes the total flow across the highway over a pre-specified length of time. DYN-OPT solves a path-based formulation in which the highway is represented by discrete segments, time is divided into periods and traffic between origins and destinations follows a user- specified distribution.

A Cooperative V2V Alert System to Mitigate Vehicular Traffic Shock Waves

Vince Rabsatt, Reuben
Gerla, Mario
2018

We address the problem of shockwave formation in uncoordinated highway traffic. The problem is caused by the combination of heavy traffic and small traffic perturbations or unexpected drivers actions. We propose a novel distributed communication protocol that helps mitigate upstream shockwave formation even with extremely low system penetration rates. Based on traffic information ahead, the Cooperative Advanced Driver Assistance System (CADAS) recommends non-intuitive velocity reductions in order to redistribute traffic more uniformly and eliminate traffic peaks. Simulation results show...