The state-of-the-art computer models TRANSYT-7F, MAXBAND, and PASSER-II for arterial signal timing are evaluated considering their capabilities in developing optimal timing plans, input data requirements, and output options. These models were applied on an 11-signal arterial to optimize various combinations of the signal control variables for two-phase and multiphase signal operation. It was found that the timings from TRANSYT-7F were better in terms of traffic performance than the settings from the bandwidth models, under fixed phasing. The settings from MAXBAND and PASSER-II produced...
This study evaluates the performance and effectiveness of the Smart Traveler Advanced Traveler Information System (ATIS). The project is designed as a field operational test of three different media approaches for providing traveler information: fully automated telephone systems, automated multi-media touch screen kiosks, and PC via modem. The program is evaluated in terms of technical function, cost, user response and overall effectiveness.
PATH AVCSS researches have been traditionally oriented toward automatic vehicle design. Recently, the field of investigation has been extended from Automated Highway System (AHS) to assistance driving systems. One of the tools built at PATH for automatic system design and assessment is SmartAHS. SmartAHS is a micro-simulation tool dedicated to the simulation of automatic vehicles and has shown to be very useful for fully automatic system simulation. These simulations permit researchers to evaluate the impact of such system on throughput improvement. In order to apply the same method to the...
This report summarizes the need for (dedicated) radio spectrum for IVHS communication services. It concludes that, if efficient architectures can be developed, several MHz of spectrum will be needed for large-scale introduction of IVHS services. Compared to most other reported estimates of the spectrum requirements, this report gives a more detailed discussion of the relation between message volume (bit/sec), the required grade of service and spectral bandwidth (Hz).
Optimal use of existing transportation facilities has become a major priority in congested urban areas. Providing real-time in-vehicle traffic information to drivers is one possibility of achieving this goal. This report documents an initial attempt to ascertain the potential benefits of a real-time in-vehicle traffic information system under recurring and non-recurring congestion conditions.
This report focuses on the DYNASMART simulation program presents a model that is capable of simulating large urban networks under various Advanced Traffic Management Systems (ATMS) and Advanced Traveler Information Systems (ATIS) strategies. It includes modules for driver responses to information and for capturing the dynamics of the network paths. The research also included the simulation study of a network in Orange County, California, where the benefits from candidate ATIS and ATMS strategies were evaluated. The DYNASMART model has evolved into a flexible tool that can be applied to...
With the advent of emerging technologies, urban intersections are being increasingly equipped with various types of video-based and in-pavement sensing systems to facilitate round-the-clock monitoring and optimization of multi-modal flows. In comparison, the assessment of the safety performance of these facilities continues to be largely based on either crash history or citizen grievances. Herein lies an opportunity to apply advanced sensing platforms to proactively monitor safety-critical events of multi-modal road users. This work presents a traffic safety monitoring framework which...
This report deals with an introduction to the control aspect of platoon maneuvers in Automated Highway Systems. The different platoon maneuvers include lane changes, merge procedures and split procedures. The first part of the report consists of a review of the existing literature in this area. The survey is split up into the quasi-synchronous and vehicle follower controller methods of approach to the problem. The subsequent sections deal with the mathematical description of the problem with two representations of the system under study, varying only in level of model complexity. The...
The purpose of this study was to demonstrate the travel and emissions impacts of urban freeway automation scenarios and to compare these to travel demand reduction scenarios, such as travel pricing and land use intensification. The Sacramento regional travel demand model set was used and an alternatives analysis was conducted. Two protocols are used to operate the model set. Results are discussed, comparing the alternative scenarios, and methodological findings are discussed, comparing the results from the two protocols for operating the model set. Methodological findings present new ideas...
