Modeling and control of variable approach lanes on an arterial road: a case study of Dalian

2018 ◽  
Vol 45 (11) ◽  
pp. 986-1003 ◽  
Author(s):  
Ronghan Yao ◽  
Xiaotong Zhang ◽  
Na Wu ◽  
Xianmin Song
Keyword(s):  
Traffic Congestion ◽  
Control Method ◽  
Time Of Day ◽  
Total Delay ◽  
Average Delay ◽  
Left Turn ◽  
Modeling And Control ◽  
Arterial Road ◽  
Variable Approach

Unbalanced directional traffic, which often exists at intersection approaches, is an important factor to induce traffic congestion on urban streets. Considering the settings of variable approach lanes, the presence of left-turn bays, and a variety of vehicle categories on an arterial road, an optimization model that minimizes the total delay is formulated and a control method that coordinates a variable sign and the corresponding signal group is put forward. To design the signal control scenarios with time of day, the procedure for using the proposed methodology is also presented in practice. To verify the given methodology, a case study is implemented using the field data and the four scenarios. The results reveal that the new methodology can better respond to the time-varying traffic flow at intersection approaches, and the provision of variable approach lanes and left-turn bays are helpful to reduce the average delay and enhance the average speed.

Modeling and Simulation of Urban Arterial Traffic Signal Coordinated Control

2014 ◽  
Vol 543-547 ◽  
pp. 1417-1422
Author(s):  
Wei Li ◽  
Xin Bi ◽  
Yun Xia Cao ◽  
Jin Song Du
Keyword(s):  
Traffic Congestion ◽  
Control Method ◽  
Coordinated Control ◽  
Traffic Monitoring ◽  
Traffic Signal ◽  
Traffic Signal Control ◽  
Monitoring And Control ◽  
Total Delay ◽  
Arterial Traffic ◽  
Urban Arterial

Traffic congestion is a major concern for many cities throughout the world. Developing a sophisticated traffic monitoring and control system would result in an effective solution to this problem. In order to reduce traffic delay, a novel urban arterial traffic signal coordinated control method is presented. The total delay of downstream and upstream vehicles is considered and the function describing the relationship between vehicles delay and signal offset among intersections is established. Finally, comparing the performance of traffic signal under method proposed in this paper with the traditional isolated traffic signal control method, the microscopic simulation results show that the method proposed in this paper has better performance in the aspect of reducing the vehicles delay. The offset model is tested in a simulation environment consisting of a core area of three intersections. It can be concluded that the proposed method is much more effective in relieving oversaturation in a network than the isolated intersection control strategy.

scholarly journals Analysis of congestion cost at signalized intersection using Vissim 9 (Case study at Demak Ijo Intersection, Sleman)

2018 ◽  
Vol 181 ◽  
pp. 06001
Author(s):  
Noor Mahmudah ◽  
Rizkie Akbar ◽  
Muchlisin
Keyword(s):  
Traffic Congestion ◽  
Traffic Volume ◽  
Signalized Intersection ◽  
Average Delay ◽  
Traffic Condition ◽  
The Road ◽  
Congestion Cost ◽  
Road Capacity ◽  
High Traffic Volume

Due to imbalance of road capacity and traffic volume, so traffic congestion will be occurred either along the road and intersection. Demak Ijo intersection is one of signalized junction located in the western part of Yogyakarta with high traffic volume so traffic congestion is frequently occurred. The aim of this study is to analyze the performance of existing traffic condition and then estimate the congestion cost at signalized intersection by modeling (simulation) using Vissim 9. The analysis results show that existing traffic condition is in very bad condition (level F), average delay of 80 seconds, average queue length of 48.73 meters with congestion cost is about Rp. 2,830,336 per hour.

scholarly journals Tandem Design of Bus Priority Based on a Pre-Signal System

2021 ◽  
Vol 13 (18) ◽  
pp. 10109
Author(s):  
Yutong Sun ◽  
Jin Li ◽  
Xiaozhong Wei ◽  
Yuling Jiao
Keyword(s):  
Traffic Congestion ◽  
Positive Impact ◽  
Urban Traffic ◽  
Signal System ◽  
Bus Priority ◽  
Total Delay ◽  
Left Turn ◽  
Before And After ◽  
Service Delays ◽  
Bus Service

Giving buses priority is an important measure to improve the attractiveness of public transport and to reduce urban traffic congestion. Reducing bus service delays as much as possible will have a positive impact on urban traffic. Based on the pre-signal system, a bus at an intersection with a left-turn special phase is optimized by “tandem design”. The design model is applied to the entrance of an intersection to study the process of vehicle arrival and departure at the main signal and pre-signal, and to calculate and analyze the delay changes of buses, straight social vehicles (meaning vehicles other than those required to be open to traffic) and left-turn vehicles before and after the adoption of “tandem design”. The results show that when the vehicle capacity at the intersection is saturated, the delays to buses and the delays of left-turn vehicles will be significantly reduced once the “tandem design” is adopted at the entrance of a cross intersection with a special left-turn phase. However, it has little effect on the delay of straight-on vehicles; with this system, the total delay experienced by straight vehicles will be reduced to one cycle.

scholarly journals Estimation of Traffic Delay Due to U-Turns at Uncontrolled Medians: Case Study in Phnom Penh, Cambodia

2021 ◽  
Vol 14 (1) ◽  
pp. 118
Author(s):  
Maksat Omarov ◽  
Syuhaida Ismail ◽  
Wan Nurul Mardiah Wan Mohd Rani ◽  
Serdar Durdyev
Keyword(s):  
Traffic Congestion ◽  
High Volume ◽  
Control Measures ◽  
Delay Model ◽  
Average Delay ◽  
Phnom Penh ◽  
Suggested Technique ◽  
Traffic Performance ◽  
Traffic Delay

Lack of infrastructure capacity to the demand in mobility results in delays in traffic. U-turns restrict the movement of the opposing through-traffic during the maneuver, hence triggering delays. Significant delays can be observed, especially in high volume traffic, where U-turning is not restricted. Hence, it is imperative to study the delays incurred by the U-turning vehicles to assess their impacts on traffic congestion. This study thus proposes a quantitative method to estimate the aggregate and average delay per vehicle caused by U-turns at uncontrolled medians of urban roads. Traffic data were collected at a corridor where vehicles were allowed to U-turn on a four-lane divided mixed traffic urban road in Phnom Penh, Cambodia. The delay in the opposing lane of traffic was calculated by analyzing the data using a novel analytical method; a derivative of the Webster’s delay model. The results reveal that the suggested technique evaluates the caused delay with good accuracy. Excessive traffic delay and about three seconds delay per vehicle in the through-traffic of the opposite lane align well with the experienced delay at the site. The method can be used to assess the delay at straight corridor sections where U-turns are not restricted, understand the causes of the delay, and develop control measures for improved traffic performance.

scholarly journals Evaluation and Analysis Model of the Length of Added Displaced Left-Turn Lane Based on Entropy Evaluation Method

2021 ◽  
Vol 2021 ◽  
pp. 1-22
Author(s):  
Binghong Pan ◽  
Jinfeng Ying ◽  
Shasha Luo ◽  
Yang Shao ◽  
Shangru Liu ◽  
...  
Keyword(s):  
Design Process ◽  
Traffic Congestion ◽  
Evaluation Method ◽  
Design Method ◽  
Urban Traffic ◽  
Assessment Model ◽  
Analysis Model ◽  
Left Turn ◽  
New Type

As the number of vehicles continues to grow in China, the problem of urban traffic congestion gets more serious, particularly at intersections. As a new type of unconventional intersection, the displaced left-turn (DLT) intersection has been widely recognized to improve the efficiency of intersections with heavy left-turn traffic flows. Converting an existing intersection into an intersection with additional DLT lanes is a valuable solution. However, the studies on DLT intersections mainly focus on performance, applicability, and safety. The guidelines on the specific engineering design process mostly come from experience, and the study on the considering multifactor design method is still insufficient. Therefore, this paper proposed an evaluation and analysis model of the lengths of added DLT lanes based on the entropy evaluation method, in which VISSIM and Surrogate Safety Assessment Model (SSAM) software were adopted for simulation. A design process for the length of the added DLT lanes was proposed with this model. An urban intersection in Xi’an was taken as a case study, and the application of the model and the design process was studied in detail. After selecting four evaluation indicators, the model was applied to calculate and analyze the optimal length of the added DLT lanes under 45 different traffic volume combinations. The recommended lengths of different situations were within the range recommended in the guidebook published by Federal Highway Administration. The results of the case study proved that the model proposed in this paper was advanced, reasonable, and practical.

scholarly journals Coordinated Control Model of Main-Signal and Pre-Signal for Intersections with Dynamic Waiting Lanes

2018 ◽  
Vol 10 (8) ◽  
pp. 2849 ◽  
Author(s):  
Chen Zhao ◽  
Yulin Chang ◽  
Peng Zhang
Keyword(s):  
Traffic Control ◽  
Control Method ◽  
Coordinated Control ◽  
Control Model ◽  
Signal Timing ◽  
Average Delay ◽  
Before And After ◽  
Traffic Volumes ◽  
Vehicle Delay

In order to alleviate the problem of the oversaturation of intersections, a traffic control method using a main-signal and pre-signals to periodically control the direction of dynamic waiting lanes was proposed in this paper. Based on the research on vehicle delay at intersections with dynamic waiting lanes and constraint relationships among a set of timing elements of the main-signal and pre-signal, a coordinated control model of a main-signal and pre-signal was built to minimize the average delay. Finally, a case study was performed to show that the proposed model is feasible. The objective optimization was performed by using a genetic algorithm to determine the main-signal and pre-signal timing scheme of the case study intersection, and then the average delay before and after installing dynamic waiting lanes was calculated and analyzed. The proposed method was found to be effective in reducing the intersection delay by 31.8% compared with the present situation of the intersection. Subsequently, the traffic volumes in the directions with dynamic waiting lanes installed were changed. It was demonstrated that with increasing traffic volumes, the effectiveness of the model to reduce intersection delay would be significant.

An Efficient Approach for Modeling and Control of a Quadrotor

2016 ◽  
Vol 4 (2) ◽  
pp. 1-16
Author(s):  
Ahmed S. Khusheef
Keyword(s):  
Pid Control ◽  
Control Method ◽  
Mechanical Design ◽  
Loop Control ◽  
Modeling And Control ◽  
Loop Control System ◽  
And Control ◽  
Close Loop Control ◽  
Close Loop Control System ◽  
Made In

 A quadrotor is a four-rotor aircraft capable of vertical take-off and landing, hovering, forward flight, and having great maneuverability. Its platform can be made in a small size make it convenient for indoor applications as well as for outdoor uses. In model there are four input forces that are essentially the thrust provided by each propeller attached to each motor with a fixed angle. The quadrotor is basically considered an unstable system because of the aerodynamic effects; consequently, a close-loop control system is required to achieve stability and autonomy. Such system must enable the quadrotor to reach the desired attitude as fast as possible without any steady state error. In this paper, an optimal controller is designed based on a Proportional Integral Derivative (PID) control method to obtain stability in flying the quadrotor. The dynamic model of this vehicle will be also explained by using Euler-Newton method. The mechanical design was performed along with the design of the controlling algorithm. Matlab Simulink was used to test and analyze the performance of the proposed control strategy. The experimental results on the quadrotor demonstrated the effectiveness of the methodology used.

scholarly journals Operational and Safety Management at Intersections: Can the Turbo-Roundabout Be an Effective Alternative to Conventional Solutions?

2021 ◽  
Vol 13 (9) ◽  
pp. 5103
Author(s):  
Vincenzo Gallelli ◽  
Giusi Perri ◽  
Rosolino Vaiana
Keyword(s):  
Traffic Congestion ◽  
Safety Management ◽  
Environmental Benefits ◽  
Assessment Model ◽  
Pollutant Emission ◽  
Emission Rates ◽  
The European Union ◽  
European Union Policy ◽  
Union Policy

The European Union policy strategies on the sustainability of the transport system pursue the goals of maximizing safety and environmental benefits and reducing the severity and frequency of crashes, congestion, and pollutant emission rates. A common issue is the planning of the most effective solution for operational and safety management at intersections. In this study, an egg turbo roundabout is proposed as the alternative solution to a conventional roundabout in Southern Italy which suffers from traffic congestion. A comparative analysis is carried out using microsimulation techniques to investigate the safety effects and operational improvements of converting a traditional priority intersection into standard roundabout or turbo roundabout layout. In particular, the VISSIM software is used to explore the most relevant operational performance measures: queue length, travel times and delays. The lowest values of these measurements are recorded for the simulated turbo roundabout, thus making this scheme more appropriate in terms of operational performances. With regard to safety analysis, the Surrogate Safety Assessment Model (SSAM) is used to collect information on the predicted number of conflicts, the probability, and severity of the potential collisions. The results suggest that, for the specific case study, the safety levels of the standard roundabout and the turbo roundabout are approximately comparable.

Sign in / Sign up

Export Citation Format

Share Document