PATH

San Gabriel Valley Smart Shuttle Technology (SGVSST) Field Operational Test Evaluation: Final Report

Giuliano, Genevieve
Moore, II, James E.
O'Brien, Thomas
Golob, Jacqueline
2002

This report presents results of the San Gabriel Valley Smart Shuttle (SGVSS) Field Operational Test (FOT). Results are drawn from a comprehensive evaluation of the FOT conducted over a three-year period. The SGVSS attempted to integrate services of three local municipal public transit operators and a regional fixed route operator via networked computer-assisted dispatching, automated vehicle location, and mobile data terminals. The integrated system was never fully deployed. We describe the project, its participants and the history of the project. The portions of the SGVSS that were...

Radio Frequency ID Tags to Enhance Safety

Misener, Jim
Li, Kang
2009

This project was originally conceived and executed to deliver a proof-of-concept of a near-term “cooperative vehicle-highway system” using a Radio Frequency Identification (RFID) tagging system to significantly improve the reliability of rear-end truck-based forward collision warning (FCW) systems. A hardware apparatus was developed but proved difficult and relatively costly to design and prototype; however, one set of RFID apparatus was delivered by our Raytheon subcontractor to PATH, then it was tested at PATH. Because of range limitations it did not perform to the extent that it could...

Development of the Capability-Enhanced PARAMICS Simulation Environment

Chu, Lianyu
Liu, Henry
McNally, Michael
Recker, Will
2005

This report summarizes research work conducted under TO4304 at the University of California, Irvine. Under this task order, the research team provided Caltrans with on-call direct support, technical guidance, and research related support. A series of Paramics plug-ins were developed and have been released to Caltrans. These plug-ins include actuated signal, multiple actuated signal timing plan, actuated signal coordination, detector data aggregator, ramp metering control, on-ramp queue override control, ALINEA ramp metering control, BOTTLENECK ramp metering control, SWARM Ramp metering...

Multi-Channel Medium Access Control for Dedicated Short Range Communications

Mak, Tony K.
Laberteaux, Kenneth P.
Sengupta, Raja
Ergen, Mustafa
2006

This paper describes a medium access control (MAC) protocol to enable multi-channel operation for dedicated short range communication (DSRC). In particular, we focus on the challenge of supporting potentially high-bandwidth commercial or info-tainment communications between vehicle and roadside in hotspots over several service channels, while concurrently enabling time-critical vehicle-vehicle communication for safety in a separate channel. In our architecture, within hotspots, communication is aided by one of the access points in the hotspot. This access point is designated the...

Dynamic Path-Based Equilibrium Assignment With Microscopic Traffic Simulation

Liu, Henry
Lianyu, Chu
Recker, Will
2005

This report summarizes research work conducted under TO4158 at the California ATMS Testbed of the Institute of Transportation Studies at the University of California, Irvine. Under this task order, the California ATMS testbed hosted two full-time PATH research postdocs (Henry Liu and Lianyu Chu) whose general responsibilities are focused on applications of ATMS in the Testbed environment. They are generally responsible for ensuring that the functional capabilities of the Testbed are designed, developed and maintained in a manner that complements and enhances the ATMS research objectives of...

Medium Access Control Protocol Design for Vehicle-Vehicle Safety Messages

Xu, Qing
Mak, Tony
Ko, Jeff
Sengupta, Raja
2005

We propose a Medium Access Control (MAC) protocol design for a vehicle to send safety messages to other vehicles. We develop a QoS model for safety messages consistent with the active safety systems literature. Each message has a range and useful lifetime. The QoS target is to have each message be received with high probability within its specified lifetime by each vehicle within its specified range. The protocol design is based on rapidly re-broadcasting each message multiple times within its lifetime in combination with the 802.11 DCF. This makes the design compatible with the emerging...

Evaluation of Incorporating Hybrid Vehicle Use of HOV Lanes

Brownstone, David
Chu, Lianyu
Golob, Tom
Nesamani, K.S.
Recker, Will
2008

This report presents a method to investigate the operational and environmental effects of the policy of allowing qualified single-occupancy hybrid vehicles to use dedicated High-Occupancy Vehicle (HOV)/carpool lanes in California.. The method combines the traditional planning method with microscopic simulation modeling. The planning method is used for demand estimation and analysis and the microscopic traffic simulation modeling method is used for accurate measures of the system. The study employs a microscopic traffic simulation model that is capable of evaluating the HOV/hybrid system...

Evaluating System ATMIS Technologies Via Rapid Estimation Of Network Flows: Final Report

Moore, II, James E.
Kim, Geunyoung
Cho, Seongdil
Hu, Hsi-hwa
Xu, Rong
1997

This report studies how flows in large scale transportation networks can be subjected to rapid estimation. It describes an efficient transportation network analysis (TNA) procedure that provides the system-wide changes of network flows under numerous scenario earthquakes. The first objective of this research is to provide reliable estimates of network flows with respect to changes in transportation networks, and to incorporate these changes to the decision-making procedures used by the California Department of Transportation (Caltrans) in making bridge retrofit decisions. The second...

Considering Risk-Taking Behavior in Travel Time Reliability

Recker, Will
Chung, Younshik
Park, Jiyoung
Wang, Lesley
Chen, Anthony
Ji, Zhaowang
Liu, Henry
Horrocks, Matthew
Oh, Jun-Seok
2005

Travel time variability is increasingly being recognized as a major factor influencing travel decisions and, consequently, as an important performance measure in transportation management. In this research project, we examine a number of questions related to travel time variability: How should travel time variability be quantified at both the section level as well as at the route level?; How do travelers value travel time and its reliability?; How much does the travel time reliability contribute to travelers' route choices?; How much variation is there in travelers' preferences regarding...

Toward Deployment of Adaptive Transit Signal Priority Systems

Li, Meng
Zhou, Kun
Yin, Yafeng
Tan, Chin-Woo
Zhang, Wei-Bin
Sun, Sonja
Leung, Kai
Lau, James
2008

This document reports the continuous efforts conducted by California PATH Program on the development and implementation of an Adaptive Transit Signal Priority (ATSP) system. The ATSP system has three distinguished features, including: (1) providing priority to transit vehicles while making a tradeoff between bus delay savings and the impacts on the rest of the traffic, (2) utilizing existing AVL/communication system already instrumented on buses to continuously monitor bus locations and predict bus arrival times to intersections and to request signal priority, and (3) building upon closed-...