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TRICEPS: An ATMIS Field Implementation for Control and Evaluation: Final Report

McNally, M. G.
Rindt, C.
Logi, F.
2002

This report summarizes a comprehensive research project directed toward the development and implementation of an Advanced Transportation Management and Information System (ATMIS) as part of the Caltrans Advanced ATMIS Testbed Program at the Institute of Transportation Studies, University of California, Irvine. The primary goal of this project was to implement this prototype ATMIS, designated TRICEPS (Testbed Realtime Integrated Control and Evaluation Prototype System), in the Irvine sub-area of the Advanced Testbed network. This sub-area represents a well-defined freeway corridor with a...

Experimental Verification of Discretely Variable Compression Braking Control for Heavy Duty Vehicles

Vahidi, Ardalan
Stefanopoulou, Anna G.
Farias, Phil
Tsao, Tsu Chin
2003

In this report a recursive least square scheme with multiple forgetting factors is proposed for on-line estimation of road grade and vehicle mass. The estimated mass and grade can be used to robustify many automatic controllers in conventional or automated heavy-duty vehicles. We demonstrate with measured test data from the July 26-27, 2002 test dates in San Diego, CA, that the proposed scheme estimates mass within 5% of its actual value and tracks grade with good accuracy. The experimental setup, signals, their source and their accuracy are discussed. Issues like lack of persistent...

Long Term Impacts of California’s Graduated Licensing Law of 1998

Cooper, Douglas
Gillen, David
2005

In July 1998 California changed its graduated driver licensing laws (GDL) for new drivers under the age of 18 to include restrictions on hours of driving, carrying teen-age passengers, and requiring more adult supervised driving practice. With fatal and injury crash data from California's Statewide Integrated Traffic Records System, this study, sponsored by Caltrans, used standard regression analysis as well as the Bai-Perron stochastic multiple structural break model to determine the effect of the law on teen-age passengers and crash rates of 16 year-old drivers. We found that in the four...

Weaving Analysis, Evaluation and Refinement

Skabardonis, Alexander
Kim, Amy
2010

Weaving sections are common design elements on freeway facilities such as near ramps and freeway to-freeway connectors. When the traffic demands exceed the capacity at weaving areas congestion may occur, which affects the operation of the entire freeway section. Traffic operational problems also may exist at weaving areas even when traffic demands are less than capacity because of the complexity of vehicle interactions, resulting in poor level of service (LOS) and potential safety problems. Existing procedures for the design and analysis of freeway weaving sections have several...

Assessing the Role of AVL in Demand Responsive Transportation Systems

Gillen, David
Raffaillac, Julie
2002

Many-to-many demand responsive transportation systems consist of vehicles which take passengers from their origins to their destinations within a service area. In dial-a-vehicle systems, in order to circumvent the undesirable feature of taxicab systems, vehicles are allowed to deviate from their direct route to serve other passengers and the emphasis is on building efficient tours to increase vehicle productivity. This strategy increases riding times but also increases average occupancy and productivity of the vehicles, and hence decreases average waiting times. A similar problem is faced...

Implementing a Kalman Filtering Dynamic O-D Algorithm within Paramics- Analysing Quadstone Won Efforts for the Dynamic O-D Estimation Problem

Garcia, Reinaldo C.
2003

This Project moves forward from the accumulated knowledge garnered from MOU 4121. Over the last year a good deal of insights was obtained about the implementation of dynamic Origin-and-Destination (O-D) estimation. Under MOU 4121, the Kalman Filtering (KF) algorithm described in Hu et al. (2000) for dynamic O-D estimation was implemented. In this research, the implemented algorithm is incorporated to the microscopic traffic simulator Paramics.Paramics offers important and unprecedented features, such as high performance and scalability, to handle realistic real world traffic networks under...

The Market for Traffic Information-Study of Industry Structure and Prospects

Chan, Shirley
Malchow, Matthew
Kanafani, Adib
1999

The market for traffic information has grown considerably in the past 10 years. Traffic information is different from other goods because the cost to users is negligible and the product is indirectly priced. As a result of these unique characteristics, the classic economic model can not be applied to determine the price or the amount of information which would be produced and consumed under competitive equilibrium. Examination of the history of traffic information as a marketable good and the structure of the market indicate that traffic information providers are experiencing significant...

Deployment and Evaluation of Real-Time Vehicle Reidentification from an Operations Perspective

Coifman, Benjamin
Varaiya, Pravin
2002

This Section improves upon the vehicle reidentification algorithm presented in Coifman and Cassidy (in press) for consecutive detector stations on a freeway; in the algorithm, a vehicle measurement made at a downstream detector station is matched with the vehicle's corresponding measurement at an upstream station. The work should be applicable to any detector technology capable of extracting a reproducible vehicle measurement, or vehicle signature. The algorithm is presented using measured vehicle lengths from conventional dual loop detectors; however it could easily be adapted to match...

Evaluation of the Anaheim Advanced Traffic Control System Field Operational Test: Final Report Task B; Assessment of Institutional Issues

McNally, M.G.
Moore, James E., II
MacCarley, C. Arthur
Jayakrishnan, R.
1999

This report provides an overview of the technical and institutional issues associated with the evaluation of the federally-sponsored Anaheim Advanced Traffic Control System Field Operations Test. The primary FOT objective was the implementation and performance evaluation of adaptive traffic signal control technologies including an existing second generation approach, SCOOT, and a 1.5 generation control (1.5GC) approach under development. Also selected for implementation was a video traffic detection system (VTDS). The SCOOT evaluation was defined relative to existing, first generation UTCS...

Parameter Estimation and Command Modification for Longitudinal Control of Heavy Vehicles

Bae, Hong S.
Gerdes, J. Christian
2003

Commercial heavy vehicles, unlike passenger vehicles, display huge variation in parameters such as vehicle mass. Coupled with lower actuation authorities (engine and brake capabilities), these variations can induce actuator saturation even in moderately demanding maneuvers, presenting challenge to the task of maintaining string stability in a platoon formation of heavy trucks. A new control scheme is proposed to put on-line bounds, or artificial saturation, on command signals via parameter estimation such that all members in a platoon can follow the reference commands without saturating...