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Communications and Positioning Systems in the Motor Carrier Industry

Scapinakis, Dimitris A.
Garrison, William L.
1991

Until recently, truck drivers and their dispatchers have relied on public telephones and voice radio systems to communicate with each other. Today, however, vendors are beginning to offer new technologies for determining the positions of trucks and communications to and from trucks. Eighteen systems and their implications for the industry and intelligent vehicle highway systems (IVHS) activities are reviewed in this paper. Some of the newer communications and/or positioning systems are in the proposal stage. Others are available with not yet fully developed capability or only in limited...

Collision Analysis of Vehicle Following Operations by Two-dimensional Simulation Model: Part I - Effects of Operational Variables

Chan, Ching-Yao
1997

This research project investigates the behaviors of vehicles in collisions, especially when they are closely spaced. The study uses a two- dimensional simulation program, EDSMAC, which allows longitudinal and lateral movements as well as the yaw motion of vehicles. The simulation model calculates impact forces in collisions and estimates the resulting vehicle damage. Collision situations are simulated. The subsequent post- impact vehicle trajectories are then analyzed. By varying parameters in simulation cases, one can evaluate the potential effects of such variables in vehicle-following...

Coding of Road Information for Automated Highways

Guldner, J.
Patwardhan, S.
Tan, H.
Zhang, W.
1997

This paper discusses coding of road information in a lateral reference system using magnetic markers designed for Automated Highway Systems ( AHS). The coding is utilized to communicate road information such as up- coming road geometry or lane merges/diverges from the roadway infrastructure to AHS vehicles. The work presented here is based on experiences with the preparation of the I-15 test track near San Diego, CA, for the National AHS Consortium demonstration in 1997. Information about road features was encoded into the magnets used as a lateral reference system for automatic steering...

Capacity of Automated Highway Systems: Effect of Platooning and Barriers

Tsao, H. S. Jacob
Hall, Randolf
Hongola, Bruce
1994

In this paper, the authors study the capacity of key Automated Highway Systems (AHS) operating scenarios. The effect of the lane-flow rule, platooning or free-agent, as well as the lane barriers, on AHS capacity are studied. Special attention is paid to the interaction between the lane-flow rule and the lane change requirement. The paper consists of two major components, analytical models and AHS simulation. After a brief introduction of AHS operating strategies, analytical models are developed for general AHS. For simulation, the authors focus on a segregated AHS that has one automated...

BTS (version 1.0) - Bottleneck Traffic Simulator User's Manual

Lin, Wei Hua
Hall, Ranolph W.
1991

Describes the computer program BTS which is a macroscopic tool for simulating the performance of freeway bottlenecks

BTS (Version 1 .1) - Bottleneck Traffic Simulator User’s Manual

Lin, Wei Hua
Hall, Randolph W.
1991

BTS can be used to evaluate a variety of changes in highway design to improve bottlenecks, such as: (1) addition of highway lanes, (2) addition of automated or HOV lanes, or (3) incident management strategies to reduce the frequency, duration and magnitude of incidents. BTS can also be used to project future highway conditions as baselevel traffic grows or driver behavior changes.The new version of BTS was enhanced to include incident dependencies, variable weather conditions, reneging, and randomly varying traffic volumes. As of yet, BTS is not capable of analyzing highway performance on...

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...

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.

Battery Charge Control with an Electro-Thermal-Aging Coupling

Hu, Xiaosong
Perez, Hector E.
Moura, Scott J.
2016

Efficient and safe battery charge control is an important prerequisite for large-scale deployment of clean energy systems. This paper proposes an innovative approach to devising optimally health-conscious fast-safe charge protocols. A multi-objective optimal control problem is mathematically formulated via a coupled electro-thermal-aging battery model, where electrical and aging sub-models depend upon the core temperature captured by a two-state thermal sub-model. The Legendre-Gauss-Radau (LGR) pseudo-spectral method with adaptive multi-mesh-interval collocation is employed to solve the...

Automated Highway System Field Operational Tests for the State of California: Potential Sites, Configurations and Characteristics

Hall, Randolph W.
Thakker, Viral
Horan, Thomas A.
Glazer, Jesse
Hoene, Chris
1997

This report describes possible objectives for a Field Operational Test (FOT), to be conducted following the completion of the National Automated Highway System Consortium (NAHSC) mission in 2002. At that time, it is anticipated that there will be one or more FOTs in which ordinary drivers will use automated vehicles on a real roadway, under test conditions. The report also identifies potential test sites in California, and evaluates the merits of these sites for conducting different types of tests.