Modeling

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...

Simulation of IVHS on the Santa Monica Freeway Corridor Using the INTEGRATION Model. Phase 2: Preliminary ATIS and ATMS Experiments

Gardes, Yonnel
May, Adolf D.
1993

The general objective of the project is to investigate and quantify the likely benefits of implementing various ATMS and ATlS control strategies on the real-life Santa Monica freeway corridor in Los Angeles.The different strategies to be tested in Phase 2 include freeway ramp metering, real-time traffic signal optimization, route guidance systems, and combinations of these strategies. Investigations of different strategies are performed for the same network conditions (portion of the Santa Monica freeway corridor previously coded in Phase 1) and under the same demand level (typical morning...

The Cell Transmission Model: Network Traffic

Daganzo, Carlos
1994

This paper shows how the evolution of multicommodity traffic flows over complex networks can be predicted over time, based on a simple macroscopic computer representation of traffic flow that is consistent with the kinematic wave theory under all traffic conditions. After a brief review of the basic model for one link, the paper describes how three-legged junctions can be modeled. It then introduces a numerical procedure for networks, assuming that a time-varying origin-destination table is given and that the proportion of turns at every junction is known. These assumptions are reasonable...

Design, Fabrication and Calibration of a Vehicle Tow Bar for Platoon Drag Measurements: A Working Report

Hong, P.
Browand, F.
Marcu, B.
1997

A longitudinal stability model for a 2 vehicle platoon yields a pair of linearly coupled equations that model the dynamics of the tow bar and the vehicles. Using reasonable approximations, the vehicle separation distance obeys a second order non-linear differential equation with constant coeficients. Spring force and damping are provided by a special shock absorber link. The towbar linkage can be made to serve as a low pass mechanical system. The design spring constant of 60 1bfAn and a damping rate of 200 lbf/ft/sec yield a low-pass system with sufficient damping and a cut of frequency of...

Behavioral Impacts Of Recurring And Incident Congestion And Response To Advanced Traveler Information Systems In The Bay Area: An Overview

Khattak, Asad J.
1993

The objective of this study is to understand how people deal with congestion and how they might respond to a multimodal Advanced Traveler Information System (ATIS). Travelers' route, departure time and mode selection decisions in response to incident and recurring congestion were investigated through a survey of Bay Area automobile commuters. This document summarizes the survey methodology, assesses representativeness of the sample and discusses the initial insights obtained from uni-variate and bi-variate analysis.

User's Manual for Transit ITS Simulator (TRAN-ITS)

Dessouky, Maged
Zhang, Lei
Singh, Ajay
Hall, Randolph
1999

This report describes a simulation model developed to evaluate the impact of using Intelligent Transportation Systems (ITS), such as Global Positioning Systems (GPS) for bus tracking, on controlling buses in wide-area transit networks. Control strategies with ITS will be compared against those without ITS (i.e., they do not rely on communication or tracking). The model is developed using a general-purpose simulation language, AweSim (Pritsker, 1997). The simulation model is generic and independent of any dedicated transit network. The model has high flexibility and can be used to simulate...

Travel Time Estimation on the San Francisco Bay Area Network Using Cellular Phones as Probes

Ygnace, Jean-Luc
Drane, Chris
Yim, Y. B.
de Lacvivier, Renaud
2000

Current traffic travel time estimates are largely based on road sensors embedded in the pavement. Today technical developments in cellular positioning and the spread of wireless phones provide the opportunity to track cell phone equipped drivers as traffic probes. The Federal Communication Commission Phase II mandate for Enhanced-911 (E-911) requires that wireless carriers must provide the location of a 911 wireless call by October 1, 2001 to the Public Safety Answering Point (PSAP), within approximately 125 meters, or under one-tenth of a mile in the majority of situations. The motivation...

A Comparison of Traffic Models: Part II Results

Lo, Hong K.
Lin, Wei-Hua
Liao, Lawrence C.
Chang, Elbert
Tsao, Jacob
1997

This working paper is the second part of a series comparing dynamic traffic flow models. It documents the results of comparison based on the framework defined in Part 1. The traffic models selected for comparison are DINOSAUR, DYNASMART, INTEGRATION, and METS. The areas of comparison comprise four categories: functionality, traffic dynamics, route choice mechanism, and network performance.The first category was compared with a checklist of functions. A total of thirteen test scenarios were constructed to compare models for the last three categories.

Traveler Response to New Dynamic Information Sources: Analyzing Corridor and Area-Wide Behavioral Surveys

Yim, Youngbin
Khattak, Asad J.
Raw, Jeremey
2004

Intelligent Transportation Systems present a well-known innovation opportunity to address urban congestion and allow greater access to transportation networks. New sources of travel information are emerging rapidly and they are likely to significantly impact traveler decisions and transportation network performance. To assess the value and impact of these new sources, this paper develops a comprehensive conceptual model based on information processing and traveler response. Specifically, the model accounts for the effect of information source, content and quality on information access and...