scholarly journals Signal Control Method for through and Left-Turn Shared Lane by Setting Left-Turn Waiting Area at Signalized Intersections

Sustainability â—½  
10.3390/su132313154 â—½  
2021 â—½  
Vol 13 (23) â—½  
pp. 13154
Author(s):  
Xiancai Jiang â—½  
Li Yao â—½  
Yao Jin â—½  
Runting Wu
Keyword(s):  
Control Method â—½  
Signalized Intersections â—½  
Signal Control â—½  
Signal Timing â—½  
Left Turn â—½  
Traffic Conflicts â—½  
Vehicle To Infrastructure â—½  
Waiting Area â—½  
Integrated Performance â—½  
Cooperation System

This paper proposes a signal control method for the through and left-turn shared lanes at signalized intersections to solve traffic conflicts between left-turn vehicles and opposing through vehicles by setting left-turn waiting area (LWA). Delays and stops are weighted to form an integrated performance index (PI) in a vehicle-to-infrastructure cooperation system. The PI models pertaining to all vehicles are established based on the LWA intersection. In addition, an optimized method of signal timing parameters is constructed by minimizing the average PI. VISSIM simulation shows that the average PI decreases by 6.51% compared with the original layout and signal timing plan of the intersection, since the increased delay of the side-road left-turn vehicles is insufficient to offset the reduced delay of the side-road through vehicles after the improvement. The sensitivity analysis shows that the greater the traffic volume of the phase including the through and left-turn shared lanes, the higher the operation efficiency of the LWA intersection compared with the typical permitted phase intersection. When the left-turn vehicles of the shared lanes in each cycle are less than the stop spaces, the LWA intersection can effectively reduce the average PI of the shared lanes. Furthermore, the more the stop spaces in the LWA, the lower the average PI in the same traffic conditions.

scholarly journals A Group-Based Signal Timing Optimization Model Considering Safety for Signalized Intersections with Mixed Traffic Flows

2019 â—½  
Vol 2019 â—½  
pp. 1-13 â—½  
Author(s):  
Fen Wang â—½  
Keshuang Tang â—½  
Keping Li â—½  
Zhigang Liu â—½  
Lin Zhu
Keyword(s):  
Optimization Model â—½  
Signalized Intersections â—½  
Signal Control â—½  
Signal Timing â—½  
Nonlinear Program â—½  
Mixed Traffic â—½  
Traffic Flows â—½  
Control Approach â—½  
Proposed Model â—½  
Traffic Conflicts

The conventional stage-based signal control approach with uniform phase structure has been dominantly applied at signalized intersections in China. However, this approach cannot efficiently handle mixed traffic flows with unbalanced volumes. Moreover, this signal control approach has resulted in many safety issues, such as traffic conflicts (a) between the right-turning motorized vehicles and the straight-through bicycles and (b) at the change of phases due to bicycles’ clearance failure. Hence, the objective of this paper is to propose a group-based signal optimization model that considers both safety and delay for the intersections with mixed traffic flows. In the proposed model, safety was evaluated based on the traffic conflicts during the inter-green period and was incorporated into the signal timing procedure. A probabilistic approach was developed to estimate the probability of occurrence of conflicts, with a novel safety indicator combining postencroachment time and kinetic energy for measuring conflict severity. The average delay per person, according to the Highway Capacity Manual 2010 method, was adopted in this paper. Then, the multiobjective optimization issue was formulated as a nonlinear program and solved by a Nondominated Sorting Genetic Algorithm. A numerical study was performed to demonstrate the applicability and performance of the proposed model. Results indicated that the proposed model can provide an effective tool for researchers and practitioners to simultaneously optimize traffic safety and efficiency in signal planning. It may also overcome the disadvantages of most of the conventional models, which are incapable of quantifying safety in the optimization process.

Operational Effects of the Consolidated Intersection Design on Urban and Suburban Arterials

2018 â—½  
Vol 2672 (17) â—½  
pp. 96-107
Author(s):  
Daniel J. Cook
Keyword(s):  
Travel Time â—½  
Signalized Intersections â—½  
Signal Timing â—½  
Left Turn â—½  
Vehicle Delay â—½  
Cycle Lengths â—½  
Expected Benefits â—½  
Traffic Signal Timing â—½  
Critical Phases â—½  
Pedestrian Crossing

Along urban and suburban arterials, closely-spaced signalized intersections are commonly used to provide access to adjacent commercial developments. Often, these signalized intersections are designed to provide full access to developments on both sides of the arterial and permit through, left-turn, and right-turn movements from every intersection approach. Traffic signal timing is optimized to reduce vehicle delay or provide progression to vehicles on the arterial, or both. However, meeting both of these criteria can be cumbersome, if not impossible, under high-demand situations. This research proposes a new design that consolidates common movements at three consecutive signalized intersections into strategic fixed locations along the arterial. The consolidation of common movements allows the intersections to cycle between only two critical phases, which, in turn, promotes shorter cycle lengths, lower delay, and better progression. This research tested the consolidated intersection concept by modeling a real-world site in microsimulation software and obtaining values for delay and travel time for multiple vehicle paths along the corridor and adjacent commercial developments in both existing and proposed conditions. With the exception of unsignalized right turns at the periphery of the study area, all non-displaced routes showed a reduction in travel time and delay. Additional research is needed to understand how additional travel through the commercial developments adjacent to the arterial may effect travel time and delay. Other expected benefits of the proposed design include a major reduction in conflict points, shorter pedestrian crossing and wait times, and the opportunity to provide pedestrian refuge areas in the median.

scholarly journals Deep Reinforcement Learning Based Left-Turn Connected and Automated Vehicle Control at Signalized Intersection in Vehicle-to-Infrastructure Environment

Information â—½  
2020 â—½  
Vol 11 (2) â—½  
pp. 77 â—½  
Author(s):  
Juan Chen â—½  
Zhengxuan Xue â—½  
Daiqian Fan
Keyword(s):  
Reinforcement Learning â—½  
Control Method â—½  
Signalized Intersection â—½  
Signal Control â—½  
Left Turn â—½  
Automated Vehicle â—½  
Whole Process â—½  
Policy Gradient â—½  
Experience Replay â—½  
Automated Vehicle Control

In order to solve the problem of vehicle delay caused by stops at signalized intersections, a micro-control method of a left-turning connected and automated vehicle (CAV) based on an improved deep deterministic policy gradient (DDPG) is designed in this paper. In this paper, the micro-control of the whole process of a left-turn vehicle approaching, entering, and leaving a signalized intersection is considered. In addition, in order to solve the problems of low sampling efficiency and overestimation of the critic network of the DDPG algorithm, a positive and negative reward experience replay buffer sampling mechanism and multi-critic network structure are adopted in the DDPG algorithm in this paper. Finally, the effectiveness of the signal control method, six DDPG-based methods (DDPG, PNRERB-1C-DDPG, PNRERB-3C-DDPG, PNRERB-5C-DDPG, PNRERB-5CNG-DDPG, and PNRERB-7C-DDPG), and four DQN-based methods (DQN, Dueling DQN, Double DQN, and Prioritized Replay DQN) are verified under 0.2, 0.5, and 0.7 saturation degrees of left-turning vehicles at a signalized intersection within a VISSIM simulation environment. The results show that the proposed deep reinforcement learning method can get a number of stops benefits ranging from 5% to 94%, stop time benefits ranging from 1% to 99%, and delay benefits ranging from −17% to 93%, respectively compared with the traditional signal control method.

scholarly journals A Novel Left-Turn Signal Control Method for Improving Intersection Capacity in a Connected Vehicle Environment

Electronics â—½  
2019 â—½  
Vol 8 (9) â—½  
pp. 1058 â—½  
Author(s):  
Chuanxiang Ren â—½  
Jinbo Wang â—½  
Lingqiao Qin â—½  
Shen Li â—½  
Yang Cheng
Keyword(s):  
Traffic Safety â—½  
Control Strategy â—½  
Control Method â—½  
Control Model â—½  
Signal Control â—½  
Signal Phase â—½  
Phase Duration â—½  
Left Turn â—½  
Intersection Signal Control â—½  
And Control

Setting up an exclusive left-turn lane and corresponding signal phase for intersection traffic safety and efficiency will decrease the capacity of the intersection when there are less or no left-turn movements. This is especially true during rush hours because of the ineffective use of left-turn lane space and signal phase duration. With the advantages of vehicle-to-infrastructure (V2I) communication, a novel intersection signal control model is proposed which sets up variable lane direction arrow marking and turns the left-turn lane into a controllable shared lane for left-turn and through movements. The new intersection signal control model and its control strategy are presented and simulated using field data. After comparison with two other intersection control models and control strategies, the new model is validated to improve the intersection capacity in rush hours. Besides, variable lane lines and the corresponding control method are designed and combined with the left-turn waiting area to overcome the shortcomings of the proposed intersection signal control model and control strategy.

Study of Feasibility Analysis for the Protected-Permissive Left-Turn Signal Control in Three-Leg Signalized Intersections Using a Microscopic Traffic Simulation Model

2015 â—½  
Vol 17 (4) â—½  
pp. 89-98 â—½  
Author(s):  
Ilsoo Yun â—½  
â—½  
Sangmin Park â—½  
Nak Won Heo â—½  
Jung Eun Yoon â—½  
...  
Keyword(s):  
Simulation Model â—½  
Traffic Simulation â—½  
Signalized Intersections â—½  
Feasibility Analysis â—½  
Signal Control â—½  
Left Turn â—½  
Microscopic Traffic Simulation â—½  
Turn Signal

Safety-Based Left-Turn Phasing Decisions for Signalized Intersections

10.3141/2619-02 â—½  
2017 â—½  
Vol 2619 (1) â—½  
pp. 13-19 â—½  
Author(s):  
Kiriakos Amiridis â—½  
Nikiforos Stamatiadis â—½  
Adam Kirk
Keyword(s):  
Urban Areas â—½  
Primary Objective â—½  
Signalized Intersections â—½  
Safety Performance â—½  
Signal Timing â—½  
Left Turn â—½  
Crash Data â—½  
Intersection Safety â—½  
Traffic Volumes

The efficient and safe movement of traffic at signalized intersections is the primary objective of any signal-phasing and signal-timing plan. Accommodation of left turns is more critical because of the higher need for balancing operations and safety. The objective of this study was to develop models to estimate the safety effects of the use of left-turn phasing schemes. The models were based on data from 200 intersections in urban areas in Kentucky. For each intersection, approaches with a left-turn lane were isolated and considered with their opposing through approach to examine the left-turn–related crashes. This combination of movements was considered to be one of the most dangerous in intersection safety. Hourly traffic volumes and crash data were used in the modeling approach, along with the geometry of the intersection. The models allowed for the determination of the most effective type of left-turn signalization that was based on the specific characteristics of an intersection approach. The accompanying nomographs provide an improvement over existing methods and warrants and allow for a systematic and quick evaluation of the left-turn phase to be selected. The models used the most common variables that were already known during the design phase, and they could be used to determine whether a permitted or protected-only phase would suit the intersection when safety performance was considered.

Modeling Capacity at Signalized Intersections with a Left-Turn Storage Bay Considering Signal Timing Plan

2019 â—½  
Vol 145 (2) â—½  
pp. 04018084
Author(s):  
Meiqi Liu â—½  
Liang Xu â—½  
Lixiao Shen â—½  
Sheng Jin
Keyword(s):  
Signalized Intersections â—½  
Signal Timing â—½  
Left Turn

scholarly journals Using Cellular Automata to Investigate Pedestrian Conflicts with Vehicles in Crosswalk at Signalized Intersection

10.1155/2012/287502 â—½  
2012 â—½  
Vol 2012 â—½  
pp. 1-16 â—½  
Author(s):  
Xiaomeng Li â—½  
Xuedong Yan â—½  
Xingang Li â—½  
Jiangfeng Wang
Keyword(s):  
Cellular Automata â—½  
Signalized Intersections â—½  
Influential Factors â—½  
Urban Traffic â—½  
Signalized Intersection â—½  
Signal Timing â—½  
Cellular Automata Model â—½  
Intersection Safety â—½  
Traffic Conflicts â—½  
Simulation Results

The operational efficiency and safety of pedestrian flows at intersections is an important aspect of urban traffic. Particularly, conflicts between pedestrians and vehicles in crosswalk are one of the most influential factors for intersection safety. This paper presents a cellular automata model that simulates pedestrian and vehicle crossing behaviors at signalized intersections. Through the simulation, we investigate the effects of different pedestrian signal timing and crosswalk widths on the crosswalk capacity, the number of traffic conflicts between pedestrians and vehicles, and pedestrian delay due to the conflicts. The simulation results indicate that the cellular automata is an effective simulation platform for investigating complex pedestrian-related traffic phenomenon at signalized intersections.

Intersection Operation with Non-Traditional Dynamic Lane Scheme through Vehicle-to-Signal Connection

2019 â—½  
Vol 2673 (8) â—½  
pp. 322-332
Author(s):  
Sida Luo â—½  
Yu (Marco) Nie â—½  
Lin Zhu
Keyword(s):  
Integer Program â—½  
Signalized Intersections â—½  
Mixed Integer â—½  
Mixed Integer Program â—½  
Time Signal â—½  
Signal Timing â—½  
Left Turn â—½  
Intersection Operation â—½  
Lane Utilization â—½  
Near Future

This paper proposes an information-based dynamic lane (IDYL) scheme for signalized intersections with exclusive left-turn phases. Similar to the tandem design, the proposed scheme aims to increase the capacity of an isolated intersection by sorting incoming vehicles based on their turning movements. Its novelty is to guide vehicles of different movements into pre-designated dynamic lanes without stopping them via pre-signal. The assumption is that vehicles themselves or their drivers have access to, and can act on, real-time signal timing information through vehicle-to-signal connection to select the correct lane to enter as they approach the intersection. A mixed integer program is proposed to optimize jointly the lane configuration, timing plan, and dynamic lane utilization for an intersection. Results from numerical and simulation experiments show that IDYL can increase the reserve capacity by more than 25% when implemented on all legs of a standard four-leg intersection, and reduce the delay by around 15% when implemented on two opposing legs. The results from this study could help traffic engineers to operate signalized intersections with dynamic lanes when vehicle-to-signal connection becomes widely available in the near future.

scholarly journals Improving schedule adherence based on dynamic signal control and speed guidance in connected bus system

2020 â—½  
Vol 3 (2) â—½  
pp. 79-88
Author(s):  
Mingjie Hao â—½  
Yiming Bie â—½  
Le Zhang â—½  
Chengyuan Mao
Keyword(s):  
Control Method â—½  
Programming Model â—½  
Signal Control â—½  
Signal Timing â—½  
Illustrative Case â—½  
Operating Speed â—½  
Content Type â—½  
Schedule Adherence â—½  
Bus Schedule â—½  
Bus System

Purpose The purpose of this paper is to develop a dynamic control method to improve bus schedule adherence under connected bus system. Design/methodology/approach The authors developed a dynamic programming model that optimally schedules the bus operating speed at road sections and multiple signal timing plans at intersections to improve bus schedule adherence. First, the bus route was partitioned into three types of sections: stop, road and intersection. Then, transit agencies can control buses in real time based on all collected information; i.e. control bus operating speed on road sections and adjust the signal timing plans through signal controllers to improve the schedule adherence in connected bus environment. Finally, bus punctuality at the downstream stop and the saturation degree deviations of intersections were selected as the evaluation criteria in optimizing signal control plans and bus speeds jointly. Findings An illustrative case study by using a bus rapid transit line in Jinan city was performed to verify the proposed model. It revealed that based on the proposed strategy, the objective value could be reduced by 73.7%, which indicated that the punctuality was highly improved but not to incur excessive congestion for other vehicular traffic. Originality/value In this paper, the authors applied speed guidance and the adjustment of the signal control plans for multiple cycles in advance to improve the scheduled stability; furthermore, the proposed control strategy can reduce the effect on private traffics to the utmost extend.

Sign in / Sign up

Export Citation Format

Share Document