Travel Behavior

Throttle And Brake Control Systems For Automatic Vehicle Following

Ioannou, P.
Xu, Z.
1994

In this paper, the authors present several throttle and brake control systems for automatic vehicle following. These control systems are designed and tested using a validated nonlinear vehicle model first and then actual vehicles. Each vehicle to be controlled is assumed to be equipped with sensors that, in addition to its own vehicle characteristics, provide measurements of the relative distance and relative speed between itself and the vehicle in front. Vehicle-to- vehicle communication required for the stability of the dynamics of a platoon of vehicles with desired constant intervehicle...

Freeway Safety as a Function of Traffic Flow: The FITS Tool for Evaluating ATMS Operations

Golob, Thomas F.
Recker, Wilfred W.
Alvarez, Veronica
2002

Understanding the benefits of improved traffic flow (reduced congestion) is critical to the assessment of investments in infrastructure or traffic management and control. Improved flow should lead to reductions in travel time, vehicle emissions, fuel usage, psychological stress on drivers, and improved safety. However, the manner in which safety is improved by smoothing traffic flow is not well understood. The documented research is aimed at shedding light on the complex relationships between traffic flow and traffic accidents (crashes).

Consumer Demand For Automated Private Travel: Extrapolations From Vanpool User Experiences

Bonanno, Nirupa
Sperling, Daniel
Kurani, Kenneth S.
1993

The purpose of this study is to investigate the reasons for an individual' s decision to ride rather than drive, and to draw any appropriate extensions to a future marketplace where automated vehicles may be an available mode choice. In the study, a focus group of existing vanpoolers is presented with the choice of driving alone or commuting with others after they had joined the vanpool. From the vanpoolers' stated choices, it is inferred whether a value may exist to future users of automated vehicles when they choose to travel in the automated mode, as opposed to driving themselves.

Real-time Density Estimation on Freeway with Loop Detector and Probe Data

Qiu, Tony Z.
Lu, Xiao-Yun
Chow, Andy H. F.
Shladover, Steven
2009

Density, speed and flow are the three critical parameters for traffic analysis. Traffic management and control with high performance require accurate estimation/prediction of distance mean speed and density for large spatial and temporal coverage. Speed, including time mean speed and distance mean speed, and flow estimation are relatively easy to be measured and estimated in the practical site, but accurate density estimation is very difficult. Inductive loop detector systems have been widely deployed, it makes better sense to fully adopt available infrastructure to achieve required...

Incident Management: Process Analysis and Improvement

Hall, Randolph W.
2001

This is the final report for the project Incident Management:Process Analysis and Improvement.The report summarizes findings from three earlier working papers (1998-31,2000-14 and 2000-15)completed under this project, and provides additional analysis on specific scenarios. This study highlights the importance of the following principles: 1)Response units should be adequate in number to handle anticipated demand. 2)Response units should be strategically located to minimize maximum response times. 3)Especially during busy periods,response units should not be dispatched over long distances.It...

SPRINTER Rail: Grade Crossing/Traffic Signal Optimization Study

Wu, Guoyuan
Li, Irene
Zhang, Wei-Bin
Johnston, Scott
Li, Meng
Zhou, Kun
2009

This report investigates impacts to local traffic operations at intersections adjacent to signal preemption by SPRINTER commuter trains and countermeasures that would minimize these impacts. Optimization models have been developed to estimate the waiting queue at the end of the preemption operation and to quickly clear the queue while minimizing overall traffic delay. Based on the optimization models, optimized signal timing plans for a total of 10 intersections were proposed, which are designed to facilitate the clearance of the queue accumulated during the preemption, as well as to...

Development and Field Testing of An Interactive Transit Station Information System (ITSIS)Using Connected Vehicle Technologies

Meng, Huadong
Tsao, Jacob
Zhou, Kun
Picar, Justin
Mizuno, Bradley
Zhang, Wei-Bin
2018

The objective of Interactive Transit Station Information System (ITSIS) is to better inform transit travelers during their trips and to enable dynamic transit operations to better serve travelers. The ultimate goal is to make transit more friendly and attractive to the traveling population such that transit will become a viable choice for travel and an integrated part of the solution for congestion relief. This report documents a research effort to develop and test a ITSIS prototype that uses Connected Vehicle technologies to enable the real-time interaction between passengers and transit...

Evaluating Wireless Broadband and System At California Safety Roadside Rest Areas

Finson, Rachel S.
Lidicker, Jeffrey
Phan, Cynthia
Rodier, Caroline
2008

To meet the demand for Internet access by the traveling public, the California Department of Transportation (Caltrans) launched a field operational test of wireless Internet access (WiFi) at two Safety Roadside Rest Areas (SRRAs), Phillip S. Raine and Enoch Christoffersen, along State Route (SR) 99 in July 2007. In this report, researchers evaluate the potential of WiFi at California’s SRRAs in order to make recommendations for future public agency participation in SRRA WiFi partnerships. A number of methods were used to gain insight into the potential of WiFi at SRRAs including (1) expert...

Assessing Benefits of Coordination on Safety in Automated Highway Systems

Choi, Woosuk
Swaroop, Darbha
2001

In this report, we present a methodology for assessing the benefits of different vehicle coordination strategies on the safety of a platoon during emergency braking. One can say that a coordinated braking strategy B is more beneficial than a strategy, if strategy B leads to a larger reduction in the probability of a collision, the expected number of collisions, and the expected relative velocity at impact as compared to strategy .We consider an emergency braking scenario, in which the lead vehicle brakes at its maximum capability and the following vehicles brake while obeying a vehicle...

Advanced Public Transportation Sytems; A Taxonomy, Commercial Availability And Deployment, Phase II

Khattak, Asad
Et. al.
1997

This study explores the development and availability of Advanced Public Transportation Systems (APTS) technologies. The study refines a taxonomy of transit technologies and uses it to explore the availability of new technologies and their impacts in transit agencies. THe taxonomy is based on defining the features, functions and performance characteristics of transit technologies. Based on the taxonomy, three surveys of technology suppliers were conducted. Questions were related to technology features, functions, performance, implementation, and impacts.0