PATH

Evaluation of Coordinated Ramp Metering (CRM) Systems in California

Mauch, Michael
Skabardonis, Alexander
2021

Freeway on-ramp metering (RM) has been extensively used as a traffic control strategy to regulate the entry of the on-ramp vehicles to prevent congestion at the freeway merging areas and preserve the freeway capacity. Benefits of RM include improved freeway travel times, improved travel time reliability, and accident reductions. Fixed-rate ramp metering strategies are based on historical data and implemented by time of day. Traffic responsive RM strategies are based on real time freeway traffic data provided by loop detectors at the vicinity of the on-ramp. Coordinated RM determine the...

Low Speed Collison Dynamics And Control: Year One Report

Tongue, Benson H.
Moon, Ahrie
1995

This report discusses the issues investigated during the first phase of a project which focuses on the development of a simulation program which will allow the study of platoon dynamics in both nominal and emergency scenarios. Preliminary issues include collision detection between the vehicles within the platoon and determining the platoon's post-crash behavior. A two-dimensional vehicle has been developed to addresses these issues. The overall simulation program includes individual modules that supply control input force, aerodynamic drag force, and road-tire interaction forces....

Model of Human Vehicle Driving - a Predictive Nonlinear Optimization Approach

Prokop, Günther
2000

When driving a vehicle the human acts as a controller in a highly dynamic environment. Thus human behavior in that control loop has to a large extent been described using control theoretical methodology. We develop a driver model, in which driving is seen as a model predictive control task in such a way that the driver accumulates knowledge about his/her vehicle's handling properties. He/she builds a model out of that knowledge and uses it to predict the vehicle's future reactions on his/her control inputs. The human's behavioral optimization is reflected in the driver model by using that...

Methods to Address Headlight Glare

Christianson, Kent B.
Greenhouse, Daniel S.
Barton, Joseph E.
Chow, Christina
2009

The goal of this project was to design, implement, and validate a computerized Glare Meter Tool that could be used in the field to assess the level of glare from headlights of opposing vehicles in a variety of situations, without relying on subjective reports of observers. Both disability glare and discomfort glare were addressed. The net result is an instrument that is capable of acquiring an image of a scene with glare, then analyzing the image to output a number on the standard, widely-used De Boer Rating Scale for Evaluation of Discomfort Glare, and also an equivalent veiling luminance...

Feasibility of A Gyroscope-free Inertial Navigation System for Tracking Rigid Body Motion

Tan, Chin-Woo
Mostov, Kirill
Varaiya, Pravin
2000

We study the feasibility of designing an accelerometer-based gyroscope-free inertial navigation system (INS) that uses only accelerometers to compute the linear and angular motions of a rigid body.

Improving Mobility Through Enhanced Transit Services: Review of the Literature for Transit Taxis

Factor, Rachel J.
Miller, Mark A.
2006

This report, an interim deliverable for Task Order 5408: “Improving Mobility through Enhanced Transit Services”, reviews the literature on the background and current potential for transit-taxi services in the United States and abroad. It documents the early tasks of a project aimed at improving the mobility of people during off-peak, low demand times of the day through innovative and alternative public transport services. To identify optimal transit-taxi concepts, we have designed a classification system defined by combinations of three service design options–fixed route, fixed-route with...

A General Framework for Verification, Simulation and Implementation of Real-Time Control Algorithms

Eskafi, Farokh H.
1999

We have proposed, investigated, and implemented a general framework for the simulation, verication, and prototyping of control algorithms for intelligent vehicles and highways. The immediate use of such frame work will be in fault management project (MOU288). Prior to this project the protocols and control algorithms developed under MOU288 should have been manually verfied, translated to a simulation language for simulation, and then modified for the QNX real-time operating system for porting to the vehicle's computer. This manual translation process is error prone at every stage. Our...

Evaluation Of The Freeway Service Patrol ( F S P ) In Los Angeles

Skabardonis, Alexander
Petty, Karl
Varaiya, Pravin
Bertini, Robert
1998

This report presents the results of a study designed to evaluate the effectiveness of the freeway service patrols (FSP) on a section of I-10 in Los Angeles. An evaluation methodology was used to estimate incident delays based on loop detector data and probe vehicles, and derive estimates of savings in performance measures in the absence of data for before FSP conditions. The estimated benefit cost ratios based on delay and fuel savings for a range of typical reductions in incident durations indicate that FSP produces significant benefits at the test site. Additional benefits include...

Position Location in AHS by Magnetic Pseudo-Noise Signals

Bana, Soheila V.
Varaiya, Pravin
1999

This paper proposes a novel method for position location by automated vehicles in AHS. The proposed positioning system meets the desired accuracy for AHS and is economically feasible because it takes advantage of the infrastructure and characteristics of the automated roads. This positioning system is very similar to GPS in the sense of using pseudo-noise codes for range measurement. The phase of a pseudo-noise signal can be mapped to the receiver's range from a reference point where the signal correlation properties in sure accurate phase estimation. The magnetic markers that are...

Model Selection And Initial Application Of CONTRAM Model For Evaluating In-vehicle Information Systems

Gardes, Yonnel
Haldors, Bruce
May, Adolf D.
1991

The objectives of this study were to select a traffic assignment and simulation model, apply that model to an integrated freeway/arterial network such as the Smart Corridor in Los Angeles, California, and, using the model, make an initial evaluation of in-vehicle information systems and the applicability of the model.