PATH

Adaptive Vehicle Traction Control

Lee, Hyeongcheol
Tomizuka, Masayoshi
1995

This report presents two different control algorithms for adaptive vehicle traction control, which includes wheel slip control, optimal time control, anti-spin acceleration and anti-skid control, and longitudinal platoon control. The two control algorithms are respectively based on adaptive fuzzy logic control and sliding mode control with on-line road condition estimation. Simulations of the two control methods are conducted using a complex nonlinear vehicle model as well as a simple linear vehicle model.

Field Demonstration and Tests of Lane Assist/Guidance and Precision Docking Technology

Tan, Han-Shue
Bu, Fanping
Johnston, Scott
Bougler, Benedicte
Zhang, Wei-Bin
Sun, Sonja
2009

This document reports the improvement and implementation of the magnetic lane-guidance and precision docking system on a 60ft articulated bus and the extensive testing on a 0.9 mile test track installed with magnets along southbound East 14th Street, San Leandro, California between 139th and 150th Avenue on a real-world operation setting. The extensive testing in the real-world setting provided valuable opportunities to discover and thus resolved a number of issues that might have prevented the system from achieving high repeatability and reliability in the future deployment on a large,...

Research Approach and Early Findings

Shaheen, Susan A.
Wright, John
2001

CarLink II is a commuter-based carsharing pilot project administered by the Institute of Transportation Studies at the University of California, Davis (ITS-Davis) in conjunction with Caltrans, American Honda Motor Company, and Caltrain. Partners for Advanced Transit and Highways (PATH) researchers are conducting the evaluation. Launched in Summer 2001, CarLink II continues the investigation of commuter-based carsharing that was originally explored in the 1998 CarLink longitudinal survey (Shaheen, 1999) and the1999 CarLink I field test (Shaheen et al., 2000). Lessons learned during the...

Experimental Study Of Chatter Free Sliding Mode Control For Lateral Control Of Commuter Buses In AHS

Hingwe, Pushkar
Tomizuka, Masayoshi
1996

This report presents design and experimental evaluation of lateral controllers for commuter buses based on Sliding Mode Control (SMC). The objective of the control is to track the lane centerline. SMC, a robust control technique, is selected as a nonlinear control strategy to take care of variation in longitudinal velocity. Two SMC based controllers are designed and are shown to differ only in the position of an integrator which gets naturally introduced into the closed loop. One of the methods is chosen for experimental verification because it guarantees asymptotic tracking with no...

Traffic Management Systems Performance Measurement: Final Report

Banks, James H.
Kelly, Gregory
1997

This report documents a study of performance measurement for Transportation Management Centers (TMCs). Performance measurement requirements were analyzed, data collection and management techniques were investigated, and case study traffic data system improvement plans were prepared for two Caltrans districts.

Global Warning Signal Integration as a Tool for Work Zone Safety and Efficiency

Cohn, Theodore E.
Barton, Joseph E.
Greenhouse, Daniel S.
Christianson, Kent B.
2006

A work zone (WZ) is visually confusing, and while no WZ looks like any other, they all share a common feature. All of them present an array of flashing light signals which are especially prominent at night. These signals ignite with no relation to one another. Each, by itself, is designed to be highly visible, attention-getting and salient, being positioned high on vehicles, along barriers and on other equipment. In this two-part study we investigated ways to make the overall visual appearance of a WZ more compatible with the needs of passers-by. The first part consisted of psychophysical...

Design Of Platoon Maneuver Protocols For IVHS

Hsu, Ann
Eskafi, Farokh
Sachs, Sonia
Varaiya, Pravin
1991

This report focuses on the design of controllers for platoons of automatically-controlled automobiles using COSPAN computer language. In order to ensure that it is safe to initiate a maneuver, the platoon layer controller enters into a negotiation with its neighbors and is implemented as a protocol. After a successful protocol termination, the actions of the vehicles involved become coordinated and the maneuver can be initiated.

Framework for Bus Rapid Transit Development and Deployment Planning

Miller, Mark A.
2004

This report presents the results of its investigation into deployment planning for bus rapid transit systems. In this study, we conducted a macro-scale examination of bus rapid transit systems from technical, operational, institutional, and planning perspectives. We then developed the theoretical foundation for a deployment planning framework for bus rapid transit systems that specifically takes into account the unique features of bus rapid transit that differ from other transit alternatives. The planning process of a BRT system can generally be divided into three inter-related stages...

Driving Safely In Smart Cars

Puri, Anuj
Varaiya, Pravin
1995

This paper considers the issue of safety in Automated Vehicle Highway Systems (AVHS). An approach is proposed for proving that a system is safe. The design for a proposed AVHS is considered and shown that if the physical controllers in the vehicles satisfy a set of constraints then the AVHS is safe. The authors contend that the problem of checking whether the controllers satisfy the constraints is equivalent to solving an optimal control problem.

Developing Operating Rules and Simulating Performance for One-dedicated-lane Bus Rapid Transit/Light Rail System

Tsao, H.-S Jacob
Dessouky, Yasser
Ingham, Kevin
Ongkowidjojo, Rocky
Tsao, Jason R.
2010

Caltrans has recently funded a project, through the Mineta Transportation Institute (MTI) at San Jose State University, about geometric and performance feasibility of using virtually only one dedicated but dynamically reversible lane to provide two-way Bus Rapid Transit (BRT) or light-rail services at the same or similar service levels as those achievable with two dedicated lanes, along the median of a busy commute corridor with at-grade crossings and regular provision of left-turn lanes. This project extended that deterministic performance study in four complementary directions. We (i)...