Wei-Bin Zhang

University of California, Berkeley | UCB · Partners for Advanced Transportation Technology (PATH)

It is commonly accepted that Automated Transit will still be as relevant as it is now, if not more so, even when fully-automated vehicles become a reality. We need to develop a consensus on how vehicle automation will transform and perhaps disrupt the traditional transit systems, what new and different types of market-driven and publicly-run framew...

Providing drivers with speed advisories is an effective eco-driving method at signalized intersections. However, all current research on speed advisory models has excluded the driver's behavior factor. In this paper, we focus on developing a speed advisory model that is able to adapt to the driver's behavior for eco-driving. First, we propose a clo...

It is widely acknowledged that deployment of vehicle-highway automation is contingent on market forces technology readiness, but in this chapter we go one step further: what is vehicle-highway automation? One hand, it is described as an evolution of the sensor and perhaps communication technologies available for Advanced Driver Assistance Systems (...

In recent years, several research projects around the globe have investigated operational concepts for truck platoons; moreover, some have experimentally demonstrated the technical feasibility of such concepts. These, or at least the demonstration scenarios they report, have been based on the convoy formation and suggest greatly reduced spacing bet...

Aiming to improve positioning precision of the GPS/INS integrated navigation system during GPS outages, a novel model combined with strong tracking Kalman filter (STKF) and wavelet neural network (WNN) algorithms for INS errors compensation is proposed and tested. STKF is used to estimate INS errors as a replacement of Kalman filter (KF), and WNN i...

Real-time highway and transit information, when presented in parallel, has the potential to influence travelers to make informed decisions to choose transit when highways are congested to save time and make the transit trip less stressful and more productive or pleasurable. The mode shifts by commuters can potentially relieve traffic congestion, re...

Increasing number of railroads have begun to operate with a moving block system that relies on a data communication system to transmit real-time information such as train position and velocity. The end-to-end communication is a critical component to ensure the efficiency and the safety of train operation. The delay in the end-to-end communication a...

Dynamic all-red extension (DARE) has recently been reported as a countermeasure to safety hazards caused by red-light running (RLR). DARE dynamically extends an all-red interval by a few seconds when detection has determined that an RLR hazard has a high probability of occurring. Previous studies of RLR prediction methods were usually based on high...

As part of a number of Intelligent Transportation (ITS) applications aimed at providing an environmental benefit, eco-approach technology is one that is feasible in the near-term. An eco-approach application uses Signal Phase and Timing (SPaT) and intersection map information of signalized intersections to provide drivers with recommendations in or...

In urban areas, conventional transit priority systems (e.g., passive priority) present some problems, such as causing too many traffic delays and degradation of on line performance due to the lack of real-time data. The purpose of this study is to develop an on line adaptive priority strategy to optimize traffic operation at a series of consecutive...

Most transit trip planning systems are based on static schedules and generate trips that do not dynamically respond to delays in transit operation caused by traffic congestion or accidents. In addition, the driving-parking- then-transit travel mode is common in metropolitan areas. However, very few transit trip planners incorporate real-time transi...

Dynamic all-red extension (DARE) has recently attracted research interest as a nontraditional intersection collision-avoidance method, for which the prediction of red-light running (RLR) and its related hazardous situations is a crucial part. We propose a probabilistic framework to model and predict RLR hazards for DARE. The RLR hazard, which is qu...

In this paper, we use second-by-second automatic vehicle location data to estimate bus emissions near far-side and near-side stops. We classify the bus running state near a stop into approach, dwell, and departure. A vehicle specific power approach is used to estimate bus emissions for each state. We show that bus emissions generated near stops can...

Most transit trip planning systems are based on static schedules and generate trips that are not dynamically responding to delays in transit operation, caused by traffic congestions or accidents. In addition, the park-and-ride travel mode is common in metropolitan areas. However, very few transit trip planners incorporate the real-time transit data...

The chief objective of the PATH2Go multimodal traveler information application is to improve the accessibility and the quality of real-time traveler information and to make transit a known and viable choice for travelers. PATH2Go was developed as part of a field test on the US-101 corridor in the San Francisco Bay Area of California, with the prima...

Mobile platforms are now becoming a more and more important medium for providing information to travelers on the move. To improve the accuracy and relevance of the mobile traveler information, context awareness has become a active research topic. In this paper, we describe algorithms and services provided by Path2Go, a multimodal traveler informati...

Majority of intersections in the United States are unsignalized. The total number of crashes at unsignalized intersections is higher than the number of crashes at signalized intersections. While stop signs have been a common safety treatment for unsignalized intersections, they also introduce additional travel delays, fuel consumption and emissions...

This article describes the development and implementation of adaptive transit signal priority (TSP) on an actuated dual-ring traffic signal control system. After providing an overview of architecture design of the adaptive TSP system, the article presents an adaptive TSP optimization model that optimizes green splits for three consecutive cycles to...

This paper describes a cost-effective traffic data collection system which is based on low bandwidth iDEN mobile network. An adaptive flow control protocol over the TCP/IP stack was developed to ensure a "best-effort" style data transmission over the low bandwidth network while the data link status is monitored to avoid unnecessary drop-offs caused...

Automobiles powered by fossil fuels are one of the major contributors to both criteria pollutant and greenhouse gas-in particular, carbon dioxide (CO2)-emissions. Previous studies revealed that unnecessary acceleration and hard braking in response to sudden changes of traffic signals may cause a significant amount of wasted energy and increased emi...

ABSTRACT 1 At arterial intersections, the red-light running (RLR) behaviors are different from that at high speed 2 intersections. While at high speed intersections drivers caught in the dilemma,zone is an important 3 contributory factor toward RLR, our study further confirms the opposite: the majority of RLRs at 4 arterial intersections were not c...

More than ever, traffic congestion is plaguing our heavily populated metropolitan areas. Transportation professionals have recognized that we cannot build our way out of this ever-increasing congestion. The challenge over the next decade is to get more out of the existing transportation system by improving its productivity. To address this challeng...

Diesel transit buses are heavy-duty vehicles that are major sources of greenhouse gases and toxic pollutants. Although various models have been used to estimate their emissions, it has been difficult to effectively apply these estimation models due to the need for user-friendly interfaces, the large amounts of underlying data, and the potential dat...

A probabilistic model is proposed to predict red light running (RLR) for collision avoidance systems at arterial signalized intersections. This RLR predictor consists of an arrival time estimator and a statistical predictor of vehicle stop-and-go maneuvers with two discrete point sensors (capable of measuring speed). In addition, unlike most predic...

Bus rapid transit (BRT) systems with dedicated lanes have shown advantages over traditional bus systems and have attracted more transit riders. However, it is not always possible to build BRT systems with double dedicated lanes because of physical and cost constraints. A BRT system with a single dedicated lane is more practical in such situations....

This paper reports on a red-light-running (RLR) prediction scheme for an intersection collision avoidance system that dynamically extends the all-red phase to avoid RLR related collisions. The paper addresses the issues of predicting the red-light running using an infrastructure-based sensor and a vehicle-to-roadside communication (Intellidrive) sy...

Motor vehicles are one of the major contributors to greenhouse gas emission inventories. Previous studies have revealed that unnecessary acceleration and hard braking in response to sudden changes of traffic signals cause a significant amount of wasted energy and increased emissions. Altering a driver's behavior can potentially contribute to the re...

The contents of this report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the State of California. This report does not constitute a standard, specification, or regulation.

The basic concept and implementation of an active priority system of light rail transit (LRT) for highway—rail grade crossings are presented. The proposed priority system consists of four major components: train detectors, train travel and dwell time predictors, priority request generator (PRG), and traffic signal controllers. As the brain of the s...

Vehicle Assist and Automation (VAA) provides the rail-like service quality by improving lateral ride smoothness, particularly at higher speeds, and by making it possible for buses to dock precisely at stations, so that wheelchair-bound riders can roll on or off the buses with a small gap between the bus floor and the loading platform at the station...

Emissions from motor vehicles are the primary cause of deterioration of urban air quality. Altering driver behavior can potentially contribute to the reduction of emissions and pollutants. Previous studies revealed that unnecessary acceleration and hard braking in response to sudden changes of traffic signals causes significant wasted energy. Provi...

This paper presents the basic concept and implementation of a light rail transit (LRT) active priority system for highway/rail grade crossings. The proposed priority system consists of four major components: train detectors, train travel and dwelling time predictor, priority request generator (PRG), and traffic signal controllers. As the “brain” of...

The effectiveness of a frontal collision warning system (FCWS) depends on the ability of its sensors and software to distinguish threatening driving scenarios and to provide the driver with a warning that leads to a safe ( collision avoidance) response. A program of testing that focused on determining the capabilities (and limitations) of the FCWS...

A critical issue encountered in implementing a transit signal priority system is to ensure that communication between transit vehicles and the traffic centre can be established for transmitting priority request and arrival time information needed for executing signal priority control. The available communication channel bandwidth, however, is not g...

San Diego Trolley has implemented a passive priority system in the San Diego downtown area since 1990. With the changes in trolley operations as well as traffic conditions in the downtown area, the passive priority system has been observed to have various limitations. In this study, by employing GPS data collection method to obtain trolley operatio...

Commercially available forward collision warning systems (FCWS) have been designed for highway use, with traffic moving in regular patterns on roadways with modest curvature. The development and the evaluation of an FCWS for urban driving are described. An urban FCWS is significantly more complicated because of irregular movements of subject (equip...

Ten years ago in August, 1997 the National Automated System Consortium (NAHSC), in partnership with the U.S. Department of Transportation, conducted a large scale demonstration of Automated Highway System on I-15 in San Diego (Demo'97). This demonstration showcased a variety of vehicle highway automation technologies that form the foundation for an...

The California Partners for Advanced Transit and Highways (PATH) Program has been the largest ITS research program in the United States. It has been leading the way in ITS research since PATH's founding in 1986, before the term ITS or its predecessor IVHS (Intelligent Vehicle Highway Systems) had even been coined. PATH's purpose is to develop found...

Not long after the California Partners for Advanced Transit and Highways (PATH) program was established, the program founders determined that a sustainable transportation system should embrace multimodal applications of ITS technologies. The PATH transit research program, benefiting from PATH'S heritage of leading research on ITS and advanced vehic...

This paper discusses the development of a system architecture for intelligent transportation systems (ITS) applications for bus rapid transit (BRT) systems. In the course of the development of system architecture, it is critical to take a system engineering approach in the development of BRT architecture to assess BRT service needs (or features), t...

We develop an algorithm for predicting the arrival time of a transit vehicle at a signalised intersection, with specific application for signal priority control. In order to accurately predict the arrival time, real-time GPS bus location information is made available. We propose an algorithm that uses both realtime and historical vehicle location i...

This report discusses the development of system architecture for Intelligent Transportation Systems (ITS) applications for Bus Rapid Transit (BRT) systems. In the course of the development of system architecture, it is critical to take a system engineering approach in the development of BRT architecture to assess BRT service needs (or features), th...

A frontal collision warning system (FCWS) for transit buses is introduced. The main purpose of the transit FCWS is to help bus drivers avoid crashes. Given the fact that buses mostly run in complex urban and suburban environments, it is a challenge for the system to give drivers timely true warnings while suppressing excessive nuisance and false wa...

Pedestrian safety is a major concern due to the vulnerability of pedestrians versus other traffic, especially in urban environment. The fatalities and injuries suffered in pedestrian collisions often intensify the perceived severity of these accidents. The problem is particularly significant for transit bus operations because their operations encou...

A theoretical model is presented to quantitatively address the relation between bus detector location and effectiveness of transit signal priority (TSP) systems, supplemented by a sample model application and simulation experiments on a real-world arterial corridor. The simulation results agree very well with results from the theoretical model. The...

The adaptive traffic signal control system, as well as the Transit Signal Priority (TSP) concept has both been viewed as important opportunities for reducing overall traffic congestions and improving bus transit services. However, few studies were conducted on combining them together. A dynamic signal timing optimization model was developed in this...

Bus Rapid Transit (BRT) is an effective alternative for providing rail-like corridor transit service. An advanced BRT concept involves the use of automated buses to provide functions of a rail transit system. A vehicle under automatic steering control following a prescribed trajectory is operated like a train on a rail. A lateral position sensing t...

A new tracking algorithm is proposed. It treats the target acceleration as a nonrandom term, and consists of a constant velocity filter an input estimator and a maneuver detector implemented in parallel. The new method has the same advantages as the two-stage Kalman estimator which requires a lesser amount of computation and provides even a better...

AIM To investigate the important role in the progress of carcinogenesis of stomach and the significance of p16 gene in the diagnosis of early gastric cancer. METHODS The expression of p16 gene mRNA in gastric mucosa of each phase from normal ones to precancerous lesions and gastric cancers were detected by in situ hybridization. RESULTS The positiv...

In the studies of advanced vehicle control and safety systems, position measurement is an important link that provides essential information for the identification of vehicle locations. One type of critical information used by vehicle control systems is the measurement of lateral position relative to a lane or a desired trajectory. Among the techno...

This paper presents the design and experimental implementation of an integrated longitudinal and lateral control system for the operation of automated vehicles in platoons. The design of the longitudinal control system include nonlinear vehicle dynamics, string-stable operation with very small inter-vehicle spacing, operation at all speeds from a c...

AIM:To reveal the inhibitory effects of Curcuma aromatica oil (CAO) on cell proliferation of hepatoma in mice. METHODS:Two tumor inhibitory experiments of CAO on hepatoma in mice were conducted. The inhibitory effects of CAO on proliferation of hepatoma in mice were evaluated by DNA image cytometry and immunohistochemical staining of proliferating...

Three types of models pertaining to the normal operation and icepack impact of snowploughs are presented. A general method of deriving a dynamic model for multiple blade snowploughs is developed. This model includes all the nonlinear terms against exciting dynamic models, which are derived under the assumption of small pitch motion and roll motion....

Advanced vehicle control and safety systems (AVCSS) involve several safety critical functions such as vehicle longitudinal and lateral control. INRETS (French Institute of Research in the Transports and Their Safety) and California PATH (Partners for Advanced Transit and Highways) of University of California at Berkeley collaborated to set up a com...

Two types of magnetic systems that have been experimentally demonstrated in recent years are presented. The characteristics of these two sensing systems are highlighted. Further, a comparison of their distinct features is given.

Keywords: Dynamic Modeling, Snowplows, Multi-Unit Vehicles, Icepack Impacts, Braking Control, Steering Control.

During manual steering of a vehicle, the information to the driver is restricted by his perception and recognition. The driver may lose such information under severe weather conditions. Look-ahead information has been shown to have great importance for vehicle steering problems. A supplementary visual display has been developed to provide both the...

To realize the benefits of advanced vehicle vontrol and safety systems (AVCSS), there is a need to establish the procedures and methodologies for safety assessment. AVCSS involves several safety critical functions such as vehicle longitudinal and lateral control. INRETS (French institute of research in the transports and their safety) and Californi...

The National Automated Highway System Consortium (NAHSC), in partnership with the Department of Transportation, demonstrated several potential AHS technologies on I-15 in San Diego in August 1997. One of the key elements in this demonstration event was a platoon system that contained a group of fully automated automobiles traveling at close spacing...

This paper discusses coding of road information in a lateral reference system using magnetic markers designed for Automated Highway Systems ( AHS). The coding is utilized to communicate road information such as up- coming road geometry or lane merges/diverges from the roadway infrastructure to AHS vehicles. The work presented here is based on exper...

The level of safety and efficiency of Automated Highway Systems (AHS) must be attainable and sustainable with a realistic cost. The analysis provided in this paper indicates that it is impractical to design and maintain an ultra reliable AHS. Consequently, fail-safe designs and infrastructure arrangements must be introduced. The paper provides a re...

Lateral motion control of a vehicle in automated highway systems (AHS) includes lane following maneuvers and lane change maneuvers. In contrast to lane following maneuvers, lane change maneuvers may be performed without direct tracking error measurement. Major substantial issues of lane change maneuvers include: (1) tracking control under the ride...

The architecture of the PATH vehicle lateral control system is presented in this paper. The two main modules are an intelligent reference/sensing system, and an Frequency-Shaped-Linear-Quadratic/preview control algorithm. The whole lateral control system was formerly evaluated on a two-door test vehicle. It was transplanted to a four-door vehicle w...

This paper concentrates on the scenario of tire blow out and it's effects on lateral control of automobiles in an IVHS environment. A computer model for the tire burst phenomenon was developed to simulate the behavior of a car with a tire blow out. Based on this modeling, a control algorithm to compensate for the tire blow out was designed. Finally...

A Fuzzy logic controller (FLC) is designed and implemented in real time on a Toyota Celica test vehicle to achieve control of the lateral motion of the vehicle. The structure of the FLC is modularized as a feedback, preview, and gain scheduling rule base. The parameters of the FLC are tuned manually using information from characteristics of human d...

Vehicle health monitoring as related to malfunction management is discussed. The needs and the functions for vehicle inspection, performance monitoring and failure detection/diagnosis are addressed. The safety critical functions of an Advanced Vehicle Control System (AVCS) and the major functions using failure mode effects and critically analysis a...

Experimental results on an automatic lane keeping control study are presented in this paper. A magnetic reference system was used to provide the vehicle lateral tracking error as well as future road curvature information and vehicle speed measurement to the vehicle steering controller. The front wheels of the vehicle are steered according to vehicl...

The accomplishments to date on the experimental evaluation of Advanced Vehicle Control Systems (AVCS) technology for highway automation in the California PATH (Partners for Advanced Transit and Highways) Program are summarized. The AVCS activities at PATH can be divided into two groups: longitudinal vehicle control and lateral vehicle control. The...

The results of an experimental work on the lateral control of a full-scaled vehicle are reported in this paper. Two control algorithms were tested, a simple PID controller to serve as the baseline, and an optimal preview controller, which was developed to improve the tracking performance, ride quality and robustness of the system. The theoretical d...

This study investigates issues concerning the implementation and impacts of lateral guidance/control systems and the phased implementation of these systems in exclusive-access High Occupancy Vehicle (HOV) lanes. The study is divided into 5 volumes. The objectives of each volume are as follows: Vol. 1: identify strategies for early deployment of lon...

This report summarizes an experimental effort in integrating and testing an automated vehicle lateral control system. The project, a cooperative effort between the California Partners for Advanced Transit and Highway ( PATH) Program and IMRA America, Inc., included a discrete roadway reference system, on-vehicle magnetic sensing system, a computer...

This paper describes the principle of an Intelligent Roadway Reference System (IRRS). It discusses both the sensing and communication capabilities of an IRRS. It then assesses the information capability of an IRRS, focusing on the ability for providing static information for an Intelligent Vehicle Highway System (IVHS). This paper also investigates...

The work presented in this paper addresses issues regarding the implementation of an integration of several specific technologies involved in achieving lateral guidance of an experimental automotive vehicle on an automated highway. Results are shown to demonstrate the feasibility of the proposed discrete magnetic marker reference/sensing system. In...