Modeling

The Cell Transmission Model. Part I: A Simple Dynamic Representation Of Highway Traffic

Daganzo, Carlos
1993

This paper presents a simple representation of traffic on a highway with a single entrance and exit. The representation can be used to predict traffic's evolution over time and space, including transient phenomena such as the building, propagation and dissipation of queues. The easy-to-solve difference equations used to predict traffic's evolution are shown to be the discrete analog of the differential equations arising from a special case of the hydrodynamic model of traffic flow. The proposed method automatically generates appropriate changes in density at locations where the...

Platoon Collision Dynamics And Emergency Maneuvering I: Reduced Order Modeling Of A Platoon For Dynamical Analysis

Tongue, Benson H.
Yang, Yean-tzong
White, Matthew T.
1991

The purpose of this three-year project is to develop an operational model of vehicle platoon dynamics under emergency conditions and to evaluate the platoon's dynamical behavior under non-nominal, or emergency, conditions. New platoon protocols and/or controller modifications will be formulated after analyzing the platoon response data in order to minimize damage to the platoon and the vehicles' occupants. This progress report discusses the results of the modeling phase of this work. A detailed literature review is included as Appendix B.

Using Cooperative Adaptive Cruise Control (CACC) to Form High-Performance Vehicle Streams. Microscopic Traffic Modeling

Liu, Hao
2018

This document summarizes the microscopic traffic simulation models used in the project entitled Using Cooperative Adaptive Cruise Control (CACC) to Form High-Performance Vehicle Streams. The major components of the microscopic traffic model include the vehicle dispatching model, human driver model and ACC/CACC model. The vehicle dispatching model determines how a modeled vehicle enters the simulation network and the distribution of different types of vehicles across the multi-lane highway. The human driver model and ACC/CACC model specify the car following and lane changing behaviors of...

National Automated Highway System Consortium: Modeling Stakeholder Preferences Project

Lathrop, John
Chen, Kan
1997

This document is the final report of the Modeling Stakeholder Preferences Project. The results of the project consist of three results: 1) evaluation framework; 2) focus group non-quantitative findings/ recommendations; and, 3) performance/impact measures, their endpoints, rankings and weights, for each stakeholder group.

Brake System Modeling, Control And Integrated Brake/throttle Switching Phase I

Hedrick, Karl
Gerdes, J.C.
Maciuca, D.B.
Swaroop, D.
1997

This report is concerned with the modeling and control issues regarding braking in an Intelligent Transportation Systems (ITS) setting. Specifically, it addresses the issue of vehicle control in an automated highway system, brake actuation and coordinated brake and throttle switching. It first presents a hydraulic model of the brake system. A method for designing stable controllers for uncertain, mismatched nonlinear system is then described. A method to estimate the coefficient between the brake pressure at the wheel and the brake torque is presented. The next section describes a...

Transient Platoon Aerodynamics During Passing Maneuvers and In-line Oscillations

Tsuei, J. L.
Savas, O.
Hedrick, J. K.
2000

The transient aerodynamic effects in a four-vehicle platoon during passing maneuvers and in-line oscillations are investigated. A vehicle model is moved longitudinally parallel to a four-car platoon to simulate passing maneuvers. The drag and side forces experienced by each platoon member are measure using strain gauge balances. The resulting data are presented as dimensionless coefficients. It is show that each car in the platoon experiences a repulsive side force when the passing vehicle is in the neighborhood of its rear half. The side force reverses its direction and becomes an...

Modeling the Santa Monica Freeway Corridor: Simulation Experiments

Skabardonis, Alexander
2002

The report describes the findings of a study to develop a simulation testbed for the Santa Monica freeway corridor. The study created one of the largest freeway corridor networks coded for the CORSIM microscopic simulation model. The coded network consists of about 10 miles of I-10 freeway and a surface street network with 75 signalized intersections. The results from the simulation experiments indicate that several CORSIM model parameters need to be adjusted in order to accurately simulate freeway facilities for California conditions. The calibrated CORSIM model produced reasonable and...

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...