PATH

Adaptive Control for MEMS Gyroscopes

Park, Sungsu
Horowitz, Roberto
Tan, Chin-woo
2002

This report presents a new adaptive operation strategy for MEMS z-axis gyroscopes. Specifically, a unified methodology is proposed for designing and analyzing the performance of a control algorithm that can identify and, in an adaptive fashion, compensate for most fabrication defects and perturbations affecting the behavior of a MEMS z-axis gyroscope. Dynamic analysis of typical MEMS gyroscopes shows that fabrication imperfections are a major factor limiting the performance of the gyroscope. However, the motion of a conventional mode-matched z-axis gyroscope does not have sufficient...

Approximate Method To Determine The Worst Case Performance Of A Nonlinear Dynamical System

Tongue, Benson H.
Packard, Andrew
1998

This report presents the theoretical development of a method to evaluate differing platoon control strategies and determine each strategy's worst case behavior under bounded parametric variations. The approach is useful in aiding a platoon designer in determining the robustness a design strategy is in the face of system uncertainties. Index Terms: traffic platooning // safety // automated highways // vehicle dynamics.

Public and Private Benefits in Intelligent Transportation Systems/Commercial Vehicle Operations: Electronic Clearance and Supply Chain Management

Gillen, David
Haynes, Matt
2002

Technological innovations have recently changed many of the ways the private trucking industry operates. These changes have enabled trucking firms to monitor more closely the distribution of goods and services, improve productivity, and develop higher levels of customer satisfaction. Of these innovations, ITS related applications play an important role in creating benefits for the private sector. ITS technologies are also increasingly offering the potential to bring about change to state and national agencies charged with overseeing goods movement in trucking. Recent research has shown...

Restructuring The Automobile/highway System For Lean Vehicles: The Scaled Precedence Activity Network (SPAN) Approach

Pitstick, Mark E.
Garrison, William L.
1991

This paper studies relative time savings between vehicles unequipped and equipped with route guidance and navigation systems. In particular, the report investigates to what extent relative travel time savings decrease as the percentage of equipped vehicles increases. In addition, some other potential services that can be provided by navigation systems are identified. The report focuses on benefits for commuters, although some results are applicable for other users.

Human Driver Model for SmartAHS

Delorme, Delphine
Song, Bongsob
2001

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...

Hierarchical Hybrid Control: A Case Study

Godbole, Datta N.
Lygeros, John
Sastry, Shankar
1995

In this paper, a case study of the difficulties encountered in the design of hierarchical, hybrid control systems is presented. The Intelligent Vehicle Highway System (IVHS) architecture proposed for vehicle platooning is used as an example. The authors conclude that the conventional tools currently is use for the design and verification of control systems may be inadequate for the design of hierarchical controllers for hybrid systems. The analysis, while indicating certain shortcomings of the current IVHS design, also contains proposed solutions to these problems.

Use of Los Angeles Freeway Service Patrol Vehicles as Probe Vehicles

Moore, II, James E.
Cho, Seongkil
Basu, Arup
Mezger, Daniel B.
2001

The Los Angeles County Metropolitan Transportation Authority/California Department of Transportation/California Highway Patrol Freeway Service Patrol (FSP) program is the largest in the nation, operating 144 service vehicles on 40 beats covering393 center-line freeway miles in Los Angeles County. The Caltrans District 7 Transportation Management Center (TMC) exercises FSP fleet control via the California Highway Patrol Computer Aided Dispatch (CAD) system. Each freeway service patrol truck is equipped with a Mobile Data Terminal (MDT), polled by the Automatic Vehicle Location (AVL) system...

Integration of Fault Detection and Identification into a Fault Tolerant Automated Highway System: Final Report

Chen, Robert H.
Ng, Hok K.
Speyer, Jason L.
Mingori, D. Lewis
2002

This report is continuation of the work of (Douglas et al., 1996) and (Douglas et al., 1997) which concerns vehicle fault detection and identification. A vehicle health monitoring approach based on analytical redundancy is described. Fault detection filters and parity equations use the control commands and sensor measurements to generate the residuals which have a unique static pattern in response to each fault. This allows the faults not only to be detected, but also identified. Sensor noise, process disturbances, system parameter variations, unmodeled dynamics and nonlinearities can...

Control Strategies And Route Guidance In Signal Controlled Networks

Skabardonis, Alexander
1991

The goal of this study was to provide a better understanding of the impacts of route guidance on urban arterials and networks controlled by traffic signals. Control and timing strategies to handle diverted traffic from the freeways to surface streets were developed and tested through simulation on real-life networks. These strategies showed that for a small number of diverted vehicles, optimal timing plans for favoring the diverted routes improved the performance of diverted traffic without significant adverse impacts to the rest of the network.

Advanced Bus Stops for Bus Rapid Transit

Dahlgren, Joy
Morris, Betsy
2005

The Santa Clara Valley Transportation Authority (VTA) is planning a bus rapid transit route on the alignment of its busiest existing route, with 30 stops in each direction. This study was conducted to determine how new technology could best be used to improve these bus stops as well as bus stops on other VTA routes and other bus systems. The study focused on bus passengers’ needs and preferences, available technologies, and the combination of improvements that would be most valued by passengers.Passenger activities at the main bus stop were observed, an on-board passenger survey was...