2013 Session: 674

• Intersection Management for Autonomous Vehicles Using Cooperative Adaptive Cruise Control Systems
  Abstract: One of the expected features for the automated vehicles in the near future is Cooperative Adaptive Cruise Control (CACC) systems. CACC systems are one of the main applications for the connected vehicles initiative of the USDOT for providing better connectivity, safety and efficient mobility in transportation. It is expected in the future that many (or most) of the vehicles will be fully automated; thus the movements of these vehicles can be optimized. Accordingly, this paper presents a new tool for optimizing the movements of autonomous vehicles through intersections: iCACC. The iCACC controller controls vehicle trajectories entering an intersection to avoid collisions while minimizing the intersection delay. In order to validate the proposed algorithm, four intersection control scenarios were analyzed, namely: a traffic signal, an all-way stop control (AWSC), a roundabout, and the iCACC controller, considering different traffic demand levels ranging from a volume-to-capacity ratio of 0.27 to 0.91. Two measures of effectiveness were considered: average vehicle delay and fuel consumption. The simulated results showed savings in delay and fuel consumption of the order of 90 and 45 percent, respectively compared to AWSC and traffic signal control. Delays for the roundabout and the iCACC controller were comparable. The simulation results showed that fuel consumption for the iCACC controller was, on average, 33%, 45% and 11% lower than the fuel consumption for the traffic signal control, AWSC and roundabout scenarios, respectively.
  Authors: Zohdy, Ismail; Kamalanathsharma, Raj Kishore; Rakha, Hesham
  Authors: Zohdy, Ismail; Kamalanathsharma, Raj Kishore; Rakha, Hesham
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-0772
• Next-Generation Intersection Control Algorithm for Autonomous Vehicles
  Abstract: This paper presents a reservation-based autonomous intersection control algorithm, named Autonomous Control of Urban TrAffic (ACUTA). The ACUTA allows centralized management of autonomous vehicles within a certain distance from the intersection to manage vehicles to pass the intersection with no conflict and few stops. To address some operational issues identified in previous studies on reservation-based autonomous intersection management, three operational improvement strategies are introduced and incorporated in the ACUTA. These strategies have been evaluated and proved to be effective under certain conditions. Along with the operational improvements of the ACUTA, its implementation in VISSIM is significant to achieve standardized evaluation of operational and safety performance using a widely applied simulation platform. This has never been accomplished in previous studies. Additionally, VISSIM simulations are established to compare the operational performances between a multi-tile ACUTA intersection and a signalized intersection and between a single-tile ACUTA intersection and a four-way stop intersection. Results obtained from both comparisons suggest that the ACUTA is more effective in maintaining a much lower intersection delay as well as a shorter or even empty queue. Sensitivity analyses are conducted on four configurable parameters of the ACUTA for a better understanding of how optimization can be done in the future. Granularity (number of tiles) is found critical in maintaining low intersection delays. Three other parameters are also found to have considerable impacts on the operational performance.
  Authors: Li, Zhixia; Chitturi, Madhav V.; Zheng, Dongxi; Bill, Andrea R.; Noyce, David A.
  Authors: Li, Zhixia; Chitturi, Madhav V.; Zheng, Dongxi; Bill, Andrea R.; Noyce, David A.
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2185
• Emissions Evaluation of Intervehicle Safety Warning Information Systems for Moving Hazards Under Connected-Vehicle Environments
  Abstract: Driver inattentiveness is one of critical factors contributing to vehicle crashes. The inter-vehicle safety warning information system (ISWS) is a technology to enhance driver attentiveness by providing warning messages about upcoming hazards using connected vehicle environments. A novel feature of the proposed ISWS is its ability to detect hazardous driving events, such as abrupt accelerations and lane changes, which are defined as moving hazards with a higher potential of causing crashes. This study evaluated the effectiveness of the ISWS in reducing vehicle emissions and its potential for traffic congestion mitigation. Reliable estimation of the ISWS¡¯s effectiveness is valuable for improving the system¡¯s functionality and for developing new technologies, in addition to establishing and applying relevant policies that will disseminate ISWS technology for safety enhancement. This study included a field experiment that documented actual vehicle maneuvering patterns for abrupt accelerations and lane changes, which were used for more realistic simulation evaluations, in addition to normal accelerations and lane changes. Probe vehicles equipped with customized on-board units consisting of a global positioning system (GPS) device, accelerometer, and gyro sensor were used to obtain the vehicle maneuvering data. A microscopic simulator, VISSIM, was used to simulate a driver¡¯s responsive behavior when warning messages were delivered. A motor vehicle emission simulator (MOVES) was then used to estimate vehicle emissions. The results show that reduction in vehicle emissions increased when the ISWS¡¯s market penetration rate (MPR) and the congestion level of the traffic conditions increased. The maximum CO and CO2 emission reductions achieved were 5.81% and 6.69%, respectively, under LOS D traffic conditions. The outcomes of this study can be valuable for deriving smarter operational strategies for ISWS to account for environmental impacts.
  Authors: Jeong, Eunbi; Oh, Cheol; Lee, Gunwoo
  Authors: Jeong, Eunbi; Oh, Cheol; Lee, Gunwoo
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2334
• Design and Implementation of Emergency Vehicle Signal Preemption System Based on Cooperative Vehicle-Infrastructure Technology
  Abstract: Emergency vehicle such as ambulance or fire truck is an important part of traffic flow. The efficiency, reliability and safety of emergency vehicle operations dropped due to increasing traffic congestion. This paper describes the design and implementation of an Emergency Vehicle Signal Preemption System (TJ-EVSP) in a Cooperative Vehicle-Infrastructure System (CVIS) environment. The system function, system architecture and operation strategies were presented. Then, the system was deployed and validated at two adjacent intersections in Taicang City, Jiangsu Province. Results show that the proposed system can improve the efficiency of emergency vehicle operations with less waste of traffic resources.
  Authors: Wang, Yinsong; Yang, Xiaoguang; Huang, Luoyi; Zhang, Lun
  Authors: Wang, Yinsong; Yang, Xiaoguang; Huang, Luoyi; Zhang, Lun
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2494
• Enhancing Roundabout Operations via Vehicle Connectivity
  Abstract: With in-vehicle automation and vehicle connectivity gaining momentum, Cooperative Adaptive Cruise Control (CACC) systems are expected to enter the market in the near future. Given that the number of roundabouts in the US has increased significantly, this research effort investigates the potential benefits of optimizing vehicle trajectories approaching a single-lane roundabout using CACC systems and vehicle to infrastructure connectivity. The optimization ensures that vehicles can enter the roundabout when gaps in the circulating roadway are available. The system is tested on a single-lane roundabout for different traffic demand and CACC market penetration levels. The study demonstrates that CACC systems could produce savings of up to 80 and 40 percent in total delay and fuel consumption levels, respectively relative to traditional roundabout control. Further benefits are also achievable if one considers the potential for reducing the time headway between CACC-equipped vehicles and thus increasing the lane capacity.
  Authors: Zohdy, Ismail; Rakha, Hesham
  Authors: Zohdy, Ismail; Rakha, Hesham
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2809
• Life-Cycle Assessment of Cooperative Vehicle Infrastructure Systems
  Abstract: Life cycle assessment is a tool that quantifies the environmental impacts of products and processes. LCA has utilized in several fields, including transportation. This paper explains fundamentals of LCA and describes transportation applications, specifically, an LCA on a cooperative vehicle-infrastructure system. Cooperative vehicle-infrastructure systems (CVIS) are the basis of Connected Vehicles technology applications promising improvements in safety, mobility, and environmental impacts. Changing to a CVIS requires renovations; primarily, adding electronics and communications hardware to vehicles and infrastructure. Electronics manufacture has been challenged for high natural resources and energy demand. This creates concern over the potential environmental benefits or drawbacks of CVIS. Despite additional electronics, vehicle fuel savings yielded enough CO2 emissions and energy reductions to offset added electronics. Over a vehicle lifetime, drivers could save a net 71 metric-tons of CO2 emissions and reduce energy use by 106 gigajoules. This mass of sequestered CO2 would require planting over 2,500 trees.
  Authors: Park, Byungkyu (Brian); Malakorn, Kristin Jade
  Authors: Park, Byungkyu (Brian); Malakorn, Kristin Jade
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2892
• Evaluation Framework of Automated Electric Transportation System
  Abstract: In the United States, the transportation sector alone accounts for almost one third of total energy use, and is responsible for one-third of the nation’s CO2 emissions. Various strategies to address the energy and environmental issues require significant reductions from the transportation sector. Automated Electric Transportation (AET) is one concept that can help to achieve this. AET’s operational concepts will allow for reduction of congestion while reducing energy required to power the vehicles, and ultimately CO2 emission. This study aims to develop an evaluation framework of the AET system. It focuses on three measures of effectiveness (MOEs): the system capacity, energy savings, and emission reduction. They are examined based on simulated vehicle activity profiles obtained from Paramics. This proposed framework should be capable of evaluating the impact due to the future implementation of AET. The advantages of AET over the conventional real-world driving pattern are also discussed.
  Authors: Jansuwan, Sarawut; Ryu, Seungkyu; Freckleton, Derek; Chen, Anthony; Heaslip, Kevin
  Authors: Jansuwan, Sarawut; Ryu, Seungkyu; Freckleton, Derek; Chen, Anthony; Heaslip, Kevin
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-3455
• Intelligent Cooperative Intersection for Improving Traffic Safety
  Abstract: New communication technologies offer the possibility to exchange data amongst vehicles and between infrastructural entities and vehicles. These opportunities have led to the new field of the Cooperative Systems in the area of Intelligent Transport Systems. A lot of research to adapt Cooperative Systems to different areas in ITS has already taken place, but Cooperative Systems are still under development as the presented review in the paper shows. One field of application is urban intersections. These are still accident prone areas despite improved safety features in vehicles and infrastructural improvements. Through the use of data exchange among the vehicles and the infrastructure the authors developed the Intelligent Cooperative Intersection Safety System – IRIS – to improve traffic safety at urban intersections. The paper presents the concept of the IRIS application and focuses on the fusion of data directly from the vehicles, road-based detectors and the traffic light controller to create an enhanced overview of the situation at the intersection by modeling the road users’ movements. This overview is assessed afterwards and if a threat for a road user is detected, a warning message is sent to the vehicles involved in the critical situation. The paper includes a report on the tests conducted at a real intersection in the City of Dortmund, Germany. These tests proved that the IRIS concept makes a valuable contribution to make urban intersections safer.
  Authors: Schendzielorz, Tobias; Mathias, Paul; Busch, Fritz
  Authors: Schendzielorz, Tobias; Mathias, Paul; Busch, Fritz
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-3887
• Headlamp Vertical Aim Impact on Performance of Lane Tracking System
  Abstract: This study examined (1) whether and how (2) vehicle headlamp vertical aiming impacts on a vision-based lane departure warning system. It was observed during the IVBSS FOT that different vehicle headlamps had different vertical aiming which resulted in different lane tracking accuracy of the Lane Deviation Warning (LDW) system. An on-road test was conducted with the lane tracking accuracy compared across five different aiming degree conditions. It was found that the lane tracking accuracy decreases with the increase of the vertical aiming. The possible explanation would be that the lane tracking systems work better with lower aimed headlamps which provides more light in the near front vehicle area (i.e., camera covering area).
  Authors: Bao, Shan; Flannagan, Michael J.; Sayer, James R.; Uchida, Mitsuhiro
  Authors: Bao, Shan; Flannagan, Michael J.; Sayer, James R.; Uchida, Mitsuhiro
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-3972
• Development and Comparison of Vehicle Preemptive Lane Keeping Systems by Steering Control
  Abstract: Vehicle run-off-road (ROR) crashes are a major safety hazard, causing almost one third of all traffic fatalities annually. Driver assistance systems can help reduce this danger. Lane-departure warning systems have already emerged in the market. However, lane-keeping and steering assist systems, which involve some level of automatic control, are still being tested. Most of these systems activate after an unintended lane departure occurs. This research presents development and comparison of two lane keeping driver assistance systems with a preemptive approach; i.e. before the vehicle leaves a lane while attempting to maintain a steer control as smooth as possible, i.e. considering the comfort and acceptance aspect of the driver in addition to safety. The first system uses two Proportional-Integral-Derivative (PID) controllers and the second one uses two Fuzzy Logic controllers. In each system, the two controller inputs are the lateral position of vehicle and the yaw angle. The steering controller has two functions; first to create a resistive stiffness to counter the driver’s steering out of a lane, and second to steer the vehicle back to the center of the lane if necessary. The systems are tested on a driving simulator in curvy scenarios. The performances of the two systems and the drivers’ acceptability are reported.
  Authors: Moreau, Johann; Eskandarian, Azim
  Authors: Moreau, Johann; Eskandarian, Azim
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-4927
• Bidirectional Control Characteristics of General Motors and Optimal Velocity Car-Following Models: Implications for Coordinated Driving in Connected Vehicle Environment
  Abstract: In natural traffic flow, the information from preceding vehicles determines driver behavior predominantly. With the availability of connected vehicle technologies (CVT), drivers can receive information from both preceding and following vehicles. This creates new opportunities for vehicle coordination and control at the microscopic level based on bi-directional information. Even though, the bi-directional car following models have been studied since 1960s. Most existing car-following models, especially those used by adaptive cruise control (ACC) technologies are still forward-only car-following models. This paper serves as a first step towards the use of bi-directional car-following models for microscopic vehicle coordination and control. We focus on studying their general control characteristics and their impact on traffic flow stability. A general bi-directional control framework is proposed to convert any car-following model into bi-directional forms. Four representative GM (General Motors) and optimal velocity car-following models are reformulated and calibrated against field vehicle trajectory data collected in the NGSIM (Next Generation SIMulation) project. The bi-directional control characteristics of the selected models are evaluated by tuning the percentage of the consideration of backward information in the final car-following decision. The evaluation uses forward versus backward acceleration diagrams and a ring road stability analysis with respect to equilibrium states obtained from the NGSIM data. The increase of backward information contribution may help alleviate traffic congestion and stabilize traffic flow. Meanwhile, an operating range of backward information contribution between 5-20% is recommended so that the resulting model can produce reasonable results for both free flow and congestion situation.
  Authors: Jin, Jing; Yang, Da; Ran, Bin; Cebelak, Meredith; Walton, C. Michael
  Authors: Jin, Jing; Yang, Da; Ran, Bin; Cebelak, Meredith; Walton, C. Michael
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-5314
• Modeling Reservation-Based Autonomous Intersection Control in VISSIM
  Abstract: Autonomous vehicles are attracting more and more attention as a promising approach to improve both highway safety and efficiency. Most previous studies on autonomous intersection management relied heavily on custom-built simulation tools to implement and evaluate their control algorithms. The use of the non-standard simulation platforms makes comparison between different systems almost impossible. Additionally, without support from standard simulation platforms, reliable and trustworthy simulation results are hard to obtain. In this context, this paper explores a way to model autonomous intersections using VISSIM, a standard microscopic simulation platform. Specifically, a reservation-based intersection control system, named Autonomous Control of Urban TrAffic (ACUTA), was introduced and implemented in VISSIM using VISSIM’s External Driver Model. The operational and safety performances of ACUTA were evaluated using the easy-to-use evaluation tools of VISSIM. Compared with the optimized signalized control, significantly reduced delays were resulted from ACUTA along with a higher intersection capacity and lower volume-to-capacity (v/c) ratios under various traffic demand conditions. The safety performance of ACUTA was evaluated using the Surrogate Safety Measure Model, and presented few conflicts among vehicles within the intersection. Moreover, the key steps and elements for implementing ACUTA in VISSIM are introduced in the paper, which can be useful for other researchers and practitioners in implementing their autonomous intersection control algorithms in a standard simulation platform. By using a standard simulation platform, performance of different autonomous intersection control algorithms can be eventually compared.
  Authors: Li, Zhixia; Chitturi, Madhav V.; Zheng, Dongxi; Bill, Andrea R.; Noyce, David A.
  Authors: Li, Zhixia; Chitturi, Madhav V.; Zheng, Dongxi; Bill, Andrea R.; Noyce, David A.
  Year: 2013
  Document Type: Paper
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2186
  Practice-Ready: Yes
• Emissions Evaluation of Intervehicle Safety Warning Information Systems for Moving Hazards Under Connected-Vehicle Environments
  Authors: Jeong, Eunbi
  Authors: Jeong, Eunbi
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2334
• Design and Implementation of Emergency Vehicle Signal Preemption System Based on Cooperative Vehicle-Infrastructure Technology
  Authors: Wang, Yinsong
  Authors: Wang, Yinsong
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2494
• Life-Cycle Assessment of Cooperative Vehicle Infrastructure Systems
  Authors: Park, Byungkyu (Brian)
  Authors: Park, Byungkyu (Brian)
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2892
• Evaluation Framework of Automated Electric Transportation System
  Authors: Jansuwan, Sarawut
  Authors: Jansuwan, Sarawut
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-3455
• Next-Generation Intersection Control Algorithm for Autonomous Vehicles
  Authors: Li, Zhixia
  Authors: Li, Zhixia
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2185
• Bidirectional Control Characteristics of General Motors and Optimal Velocity Car-Following Models: Implications for Coordinated Driving in Connected Vehicle Environment
  Authors: Jin, Jing
  Authors: Jin, Jing
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-5314
• Modeling Reservation-Based Autonomous Intersection Control in VISSIM
  Authors: Li, Zhixia
  Authors: Li, Zhixia
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Operations and Traffic Management
  Session: 674
  Paper Number: 13-2186