Intersection Delay Research Articles

DAMPAK PETUGAS PENGATUR LALU LINTAS TERHADAP KINERJA SIMPANG 4 TAK BERSINYAL JALAN AGRO-BOUGENVILE (LEMBAH UGM), YOGYAKARTA

The arrangement of peak traffic flow in unsignalized intersections usually carried out by illegal traffic wardens (PTR) and legal traffic wardens (PR).Additionally, t raffic management implemented by PTR and PR only during peak hours. This research was executed in4 unsignalized Intersection at Agro street – Bougenville stree t (Lembah UGM) , Sleman. The high traffic volume without the arrangement at the intersection caused traffic jam, so the performance level decreased. This study aimed to determine the impact of PTR and PR and find out alternative solutions at the intersection . The method s for obtaining primary data were by surveying traffic volume data, vehicle speed data, queue length data, driving behaviour s and geometry in the field. The data analysis in this study used VISSIM 9.0. The intersection condition without traffic management of wardenshad delay as much as 21 , 93 seconds with level of service (LOS) C. Intersections management with PTR produced a value of intersection delay was 30,02 seconds with level of service ( LOS ) D. Intersections management with PR produced a value of intersection delay was 29 , 20 seconds with level of service ( LOS ) D. This result showed that the performance of the intersections in all conditions were worse conditions. The alternative solution in this research was traffic signal with average delay value was 30,31 seconds with level of service ( LOS ) D. Hopefully, m anagement intersections with traffic signals could reduce accidents risk at intersections.

A Mixed Path Size Logit-Based Taxi Customer-Search Model Considering Spatio-Temporal Factors in Route Choice

This paper introduces a model to analyze route choice behavior of taxi drivers for finding next passenger in urban road network. Considering the situation of path overlapping between selected routes in the process of customer-searching, a mixed path size logit (MPSL) model is proposed to analyze route choice behaviors through considering spatio-temporal features of route including customer generation rate, path travel time, cumulative intersection delay, path distance, and path size. Specially, customer generation rate is defined as attraction strength based on historical pick-up records in the route, the intersection travel delay and path travel time are estimated based on large scaled taxi global positioning system (GPS) trajectories. In the experiment, the GPS data were collected from about 36000 taxi vehicles in Beijing at 30-s interval during six months. In the model application, an area of approximately 10 square kilometers in the center of Beijing is selected to demonstrate the effectiveness of the proposed model. The results indicated that the MPSL model could effectively analyze the route choice behavior in customer-searching process and express higher accuracy than traditional multinomial logit model and basic PSL model.

A Dynamic Predictive Traffic Signal Control Framework in a Cross-Sectional Vehicle Infrastructure Integration Environment

With the development of modern wireless communication technology, especially the vehicle infrastructure integration (VII) technology, vehicles’ information such as identification, location, and speed can be readily obtained at upstream cross-section. This information can be used to support traffic signal timing optimization in real time. A dynamic predictive traffic signal control framework for isolated intersections is proposed in a cross-sectional VII environment, which has the ability to predict vehicle arrivals and use this to optimize traffic signals. The proposed dynamic predictive control framework includes a dynamic platoon dispersion model (DPDM) which uses the vehicles’ speed data from the cross-sectional VII environment, as opposed to traditional vehicle passing/existing data, to predict the arriving flow distribution at the downstream stop-line. Then, a dynamic programming algorithm based on the exhaustive optimization of phases (EOP) is proposed working in rolling optimization (RO) scheme with a 2s time horizon. The signal timings are continuously optimized by regarding the minimization of intersection delay as the optimization objective, and setting the green time duration of each phase as a constraint. In the end, the proposed dynamic predictive control framework is tested in a simulated cross-sectional VII environment and a case study carried out based on a real road network. The results show that the proposed framework can reduce the average delay and queue length by up to 33% and 35%, respectively, compared with the traditional full-actuated control.

DCL-AIM: Decentralized coordination learning of autonomous intersection management for connected and automated vehicles

Conventional intersection managements, such as signalized intersections, may not necessarily be the optimal strategies when it comes to connected and automated vehicles (CAVs) environment. Autonomous intersection management (AIM) is tailored for CAVs aiming at replacing the conventional traffic control strategies. In this work, using the communication and computation technologies of CAVs, the sequential movements of vehicles through intersections are modelled as multi-agent Markov decision processes (MAMDPs) in which vehicle agents cooperate to minimize intersection delay with collision-free constraints. To handle the huge dimension scale incurred by the nature of multi-agent decision making problems, the state space of CAVs are decomposed into independent part and coordinated part by exploiting the structural properties of the AIM problem, and a decentralized coordination multi-agent learning approach (DCL-AIM) is proposed to solve the problem efficiently by exploiting both global and localized agent coordination needs in AIM. The main feature of the proposed approach is to explicitly identify and dynamically adapt agent coordination needs during the learning process so that the curse of dimensionality and environment nonstationarity problems in multi-agent learning can be alleviated.The effectiveness of the proposed method is demonstrated under a variety of traffic conditions. The comparison analysis is performed between DCL-AIM and the First-Come-First-Serve based AIM (FCFS-AIM), with Longest-Queue-First (LQF-AIM) policy and the signal control based on the Webster’s method (Signal) as benchmarks. Experimental results show that the sequential decisions from DCL-AIM outperform the other control policies.

Analysis of traffic flow with micro-cars with respect to safety and environmental impact

This study analyzes the characteristics of traffic flow in the presence of micro-cars in a vehicle mix. A two-lane multi-cell traffic cellular automaton (TCA) model is formulated to simulate mixed traffic flow comprising conventional passenger cars and micro-cars. The segments of an urban highway and arterial road, both with two lanes and measuring 700 m in length, are simulated; the latter includes an intersection delay with a signal cycle at the midpoint. Traffic flows with different proportions of micro-cars are investigated in the simulation. Four aspects of traffic conditions are calculated: the number of lane changes, the number of decelerations, the coefficient of speed variation (which may be indicative of safety performance), and the HC, CO, and NOx emissions (as a measure of environmental impact). The simulation results suggest that mixed flow with micro-cars leads to higher frequencies of lane-changing on both highways and arterial roads, although the incremental change on the latter is smaller. With the introduction of micro-cars on the highway, the frequency of decelerations increases in free flow and decreases in congested flow; however, on the arterial road, it decreases the frequency of decelerations and has an insignificant impact on free flow. The introduction of micro-cars has a similar impact on the coefficient of speed variation. Under free flow conditions on highways, the introduction of micro-cars has a negative influence on the three aforementioned parameters related to safety. However, for free flow on arterial roads or congested flow on highways and arterial roads, the results are inconclusive because the effect of micro-cars is contradictory in terms of the three parameters. Vehicle emissions, such as HC, CO, and NOx, increase during free flow on highways, but are always lower on arterial roads.

Traffic Assessment for Completion of Road Upgrading from Secondary Road to Dual Carriageway

A traffic study was carried out at the signalized intersections to assess the road condition after a road upgrading from secondary road (3 m wide lane) to dual carriageway (3.5 m wide lane). The site selected was Tudan Road, which is located in Miri City in Sarawak State, Malaysia, and it is about 20-minute drive from the Border of Brunei Darussalam. Tudan Road connects Kuala Baram Bypass and Lutong-Kuala Baram Road with traffic light intersections. Traffic count data was collected at both intersections of Kuala Baram Bypass and Lutong-Kuala Baram Road by recording the traffic volume for every 15 minutes interval during an hour period of morning and afternoon peak hours. The collected data were then analysed according to Highway Capacity Manual (HCM) 2010 to determine Level of Service (LOS). By using the traffic volume collected, the LOS was estimated for Tudan Road as a secondary road prior to upgrading. The results indicated that the LOS during weekend afternoon has improved from Level F to B for Lutong-Kuala Baram Road intersection and Level F to D for Kuala Baram Bypass intersection after the upgrading of Tudan Road to dual carriageway. During weekday afternoon, the LOS for both intersections has also improved. The LOS for both intersections varied between morning and afternoon, and between weekday and weekend. The variation is caused by changes in lane capacity and volume-to-capacity ratio for different periods when the road users might actively commute for daily work or some leisure activities. Intersection delay time reduced 50% at Lutong-Kuala Baram Road and 74% at Kuala Baram Bypass after the road upgrading. From the LOS analysis, it proved that the upgrading of Tudan road has improved intersection performance at Lutong-Kuala Baram Road and Kuala Baram Bypass with different levels depending on morning or afternoon, and weekday or weekend.

ANALISIS KINERJA SIMPANG TIGA TAK BERSINYAL

Simpang Lamlo is one of No-Signal Three-way Junctions in National Road from Banda Aceh to Medan as a Main road and is connected directly to the Cross-Regional Road that is from Beureuneun to Geumpang as the Minor Road and vice versa. The purpose of this study is to analyze the performance of the No-Signal Three-Way Junctions by using the Indonesian Highway Capacity Manual 1997. Data required in this study are primary and secondary data. The primary data is in the form of the condition data of traffic, intersection geometric, and environment. Secondary data includes the population growth and the map of the road network. Traffic data were collected by using video recording on Monday, Wednesday and Saturday at 7.00 a.m. – 9.00 a.m., 12.00 p.m. – 2.00 p.m and 5.00 p.m. – 7.00 pm. These data were processed by using Microsoft Excel based on MKJI 1997 and and the results were made in the form of tables and graphics. From the tables and graphics, it could be known for the traffic volume, composition, and the peak hours occured in the intersections. The calculation on the peak hour with the current highest peak is on Monday, 5.00 p.m. - 6:00 p.m. in which the traffic volume at the intersection is 2737 (smp / hour). The capacity value of the existing condition in Simpang Lamlo is 2762 (smp / hour). The traffic delay in the intersection is 11,63 (det / smp). The degree of saturation at the existing condition is 0.99, higher than the provision in Indonesian Highway Capacity Manual which is 0,75. The intersection delay value is 15.64 (det / smp) and the queue chance at the intersection is 39,43% to 77,98%,

Pedestrian Delay Model for Continuous Flow Intersections under Three Design Patterns

In order to accurately evaluate the level of service of pedestrians and provide the basis for the optimized design, the pedestrian delay of the continuous flow intersection was analyzed. According to the characteristics of streams of pedestrians’ arriving and leaving, the pedestrian delay models of different directions (namely, straight and diagonal) were established for three pedestrian passing patterns of the continuous flow intersection. The accuracy of the models was verified by VISSIM. The deviation was less than 3%. The effects of three key factors, namely, the vehicle demands, pedestrian demands and percentage of diagonal crossing, on the delay of the pedestrian under three modes were discussed by sensitivity analysis. The results show that the traditional pedestrian passing pattern mainly applies on the conditions that vehicle and pedestrian demands are low. The pattern of interspersed pedestrian passing is mainly applicable to the conditions of high vehicle and pedestrian demands. Although the pattern of exclusive pedestrian passing phase was least selected as the optimal design, it can apply to traffic demand fluctuating condition for its insensitive to volume and pedestrian demand pattern.

A study of the environmental impacts of intelligent automated vehicle control at intersections via V2V and V2I communications

This article presents a novel intersection traffic management system for automated vehicles and quantifies its impact on fuel consumption and greenhouse gas emissions of CO2 relative to traditional traffic signal and roundabout intersection control. The developed intelligent traffic management (ITM) techniques, which are based on a spatiotemporal reservation scheme, ensure that vehicles proceed through the intersection without colliding with other vehicles while at the same time reducing the intersection delay and environmental impacts. Specifically, the spatiotemporal reservation scheme provides each vehicle a collision-free path that is decomposed into a speed profile along with navigational instructions. The integration of the developed microscopic traffic simulator with instantaneous emission model, provides improved assessments of the environmental impact of traffic control strategies at intersections. The simulator architecture integrates several ITM algorithms, vehicle sensors, V2V/V2I communications, and emission and fuel consumption models. Each vehicle is modeled by an agent and each agent provides information depending on the specific vehicle sensors. The ITM system is supported by V2V and V2I communications, allowing the exchange of information among vehicles and infrastructure. The data include the estimated vehicle position and speed. Compared with traditional traffic management techniques, the simulation results prove that the proposed ITM system reduces CO2 emissions significantly. The research also shows that these reductions are more significant when the traffic flow increases.

An optimization model of signal timing plan and traffic emission at intersection based on Synchro

With the rapid development of urbanization in China, the pressure of urban traffic keeps increasing. The problem of traffic pollution is increasingly serious as the automobile exhaust has been one of the main sources of urban air pollution. The major causes of traffic emission are the traffic jam and delay in the urban road intersections. Many advanced traffic signal control methods have been widely applied in the traffic management to reduce traffic jam. This paper proposes an optimization model of signal timing plan that comprehensively considers operating efficiency and traffic emission, which is based on signal timing plan for building a model of network topology and simulation for optimizing the signal timing. Meanwhile, this plan is to improve the efficiency of intersections, reduce queuing time and harmful emission. Taking some intersections in Harbin as an example, the measured pollutant emissions data at the intersections before and after signal optimization were collected and compared, then the levels of vehicle exhaust pollution and emissions of various emissions under different control strategies were analyzed, thus the emissions under different traffic management and control were evaluated. All these data has a great importance both in theoretical and practical value.

A Combinatorial Dynamic Network Trajectory Reservation Algorithm for Connected Autonomous Vehicles

We present a combinatorial assignment algorithm for reserving space-time trajectories from origins to destinations given an ordered list of vehicles. Space-time trajectories include guaranteed arrival times at every node in the path, including at the destination. Traffic flows are modeled using the cell transmission model, a Godunov approximation to the kinematic wave model. Space-time trajectories are constructed to follow the cell transmission model constraints and first-in-first-out behavior. Reservation-based intersection control for connected autonomous vehicles, which determines intersection access and delays for individual vehicles, is used to ensure that reserved trajectories are followed. The algorithm is suitable for city networks. Results show that vehicles with higher priority tend to have much lower travel times. In addition, the trajectory reservation system reduced overall congestion in the network compared with dynamic user equilibrium assignments.

Trajectory planning for autonomous intersection management of connected vehicles

This paper proposes a cooperative scheduling mechanism for autonomous vehicles passing through an intersection, called TP-AIM. The main objective of this research is to ensure safe driving while minimizing delay in an intersection without traffic lights. Firstly, an intersection management system, used as an info-collecting-organizing center, assigns reasonable priorities for all present vehicles and hence plans their trajectories. Secondly, a window searching algorithm is performed to find an entering window, which can produce a collision-free trajectory with minimal delay, besides backup windows. Finally, vehicles can arrange their trajectory individually, by applying dynamic programming to compute velocity profile, in order to pass through intersection. MATLAB/Simulink and SUMO based simulations are established among three types of traffic mechanisms with different traffic flows. The results show that the proposed TP-AIM mechanism significantly reduces the average evacuation time and increases throughput by over 20%. Moreover, the paper investigates intersection delay, which can be reduced to less than 10% compared to classical light management systems. Both safety and efficiency can be guaranteed in our proposed mechanism.

Mixed-Integer Linear Programming for Optimal Scheduling of Autonomous Vehicle Intersection Crossing

We propose an urban traffic management scheme for an all connected vehicle environment. If all the vehicles are autonomous, for example, in smart city projects or future's dense city centers, then such an environment does not need a physical traffic signal. Instead, an intersection control server processes data streams from approaching vehicles, periodically solves an optimization problem, and assigns to each vehicle an optimal arrival time that ensures safety while significantly reducing number of stops and intersection delays. The scheduling problem is formulated as a mixed-integer linear program (MILP), and is solved by IBM CPLEX optimization package. The optimization outputs (scheduled access/arrival times) are sent to all approaching vehicles. The autonomous vehicles adjust their speed accordingly by a proposed trajectory planning algorithm with the aim of accessing the intersection at their scheduled times. A customized traffic microsimulation environment is developed to determine the potentials of the proposed solution in comparison to two baseline scenarios. In addition, the proposed MILP-based intersection control scheme is modified and simulated for a mixed traffic consisting of autonomous and human-controlled vehicles, all connected through a wireless communication to the intersection controller of a signalized intersection.

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

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 autonomous connected platoon-based system for city-logistics: development and examination of travel time aspects

ABSTRACT This paper proposes a system providing city-logistic services, based on the use of autonomous-connected platoons consisting of delivery vans. The proposed system is tested using a microsimulation. The focus of the analysis lies on the travel times of the delivery vans. The travel time is examined focusing on three parameters related to the size and number of platoons, and number of non-platoon vehicles. The most dominant parameter found is the number of platoons in the system. This parameter has two contradicting effects: increasing this number can decrease the waiting time while switching between platoons, but at the same time increases the intersection delay. A comparison to non-platoon scenarios, representing the current state shows that the proposed system can improve in some cases the current state of the network. In addition to model development, this work also includes the development of an algorithm for regulating the behavior of platoons in roundabouts.

A New Approach for Real-Time Traffic Delay Estimation Based on Cooperative Vehicle-Infrastructure Systems at the Signal Intersection

Confined by the real-time and accuracy of traditional traffic collecting parameters, the existing traffic delay estimation models are generally with poor performance in guiding practical applications. In the Cooperative Vehicle-Infrastructure System, the real-time entire space-time driving state information of a single intelligent vehicle provides new data supporting for road traffic status evaluation. Fully extracting the value of this kind of new data, this paper proposes a new real-time traffic delay estimation method based on the Webster signalized intersection delay model. Taking each intelligent vehicle as a benchmark point, the vehicle arriving/leaving characteristics of the signalized intersection are spatially interpolated by the stopping state of a small amount of benchmark vehicles. In order to obtain the critical queuing dissipation point, the linear fitting method is used to forecast the critical stopping time and further the Markov model is used to estimate the number of queuing vehicles at the critical stopping time. Based on the real-time vehicle queuing characteristics, a new traffic delay estimation model is built according to the Webster estimation mechanism. The case study shows that, compared with the traditional Webster model, the proposed method can effectively improve the traffic delay estimating accuracy.

Automated intersection delay estimation using the input–output principle and turning movement data

Abstract Vehicle delay is one of the most important performance measures of effectiveness (PMOE) in intersection traffic operations. It allows traffic engineers to evaluate the performance of a traffic system component or the effectiveness of the system-wide control strategy. It is often utilized for real-time applications such as adaptive signal control, congestion management, and dynamic traffic assignment. However, obtaining intersection performance data in real time such as intersection control delay can be very time consuming and labor intensive. This paper develops and tests a reliable method called the Automated Vehicle Delay Estimation Technique (AVDET), which automatically estimates delay at a signalized intersection using detector data and signal timing information from the existing traffic signal controller. Results from the delay estimation algorithm were compared with those from simulation, followed by statistical tests under varying traffic operation conditions. The findings showed that AVDET was able to provide effective results under different traffic and signal control scenarios. Future work of field implementation for the proposed algorithms is recommended to investigate the model reliability and effectiveness in real-time traffic conditions.

Measuring the Influences and Impacts of Signalized Intersection Delay Reduction on the Fuel Consumption, Operation Cost and Exhaust Emissions

With the rapid urban expansion and economic development, vehicle fuel dissipation and exhaust emissions have been identified as major energy wastage and urban air pollutions in Kalar City and Iraqi Kurdistan Region in general. Traffic congestion is a growing problem in Kalar City and other urban areas. As it increases, the delay at the transportation network will increase. Any increase of the delay in the transportation network will reflect negatively by increasing the delay at the signalized intersections. Therefore, a study on delay and its relation to fuel consumption, operation cost and emissions at signalized intersection are necessary. This paper, studies the influences and impacts of signalized intersection delay reduction on the fuel consumption, operation cost, and exhaust emissions. A simulation is carried out to evaluate the existing conditions of selected intersections by estimating the intersection delay, operation cost, and emissions. The simulation results show that fuel consumption, operation cost, and emissions are high and directly proportional to the intersection delay. To reduce intersection delay, a signal timing optimization is carried out to the selected intersections. The optimization results show that the delay reduction has a significant influence and impacts in reducing; fuel wastage, operation cost, and exhaust emissions.

Estimation Delay Variation and Probability of Occurrence of Different Level of Services Based on Random Variations of Vehicles Entering Signalized Intersections

Estimation of delay in signalized intersection is a difficult and complicated process that depends on many variables. Among the factors influencing the intersection delay, variable of saturation degree (Xc) is one of the most important variables. In the present study, a new analytical method has been proposed for calculating delay variation at isolated intersections in under-saturated condition and under the influence of different number of vehicles entering to the intersections. Generally, the average delay for average number of vehicles entering intersection is currently calculated by the point to point method; then, the level of service of intersection is specified from the resulting delay. In the meantime, the influence of different number of vehicles entering to the intersections cannot be seen in such methods. But for the presented method in this paper the delay is expressed as a range of values for different values of saturation degree and different numbers of vehicles entering the intersections that it leads to achieve more real results from intersection's level of service.

Speed, travel time and delay for intersections and road segments in the Montreal network using cyclist Smartphone GPS data

Very little is known about cyclist speeds and delays at the disaggregate level of each road segment and intersection in an entire city network. Speeds and delays serve as vital information for planning, navigation and routing purposes including how they differ for different times of the day and across road and bicycle facility types, after controlling for other factors. In this work, we explore the use of recent GPS cyclist trip data, from the Mon RésoVélo Smartphone application, to identify different performance measures such as travel time, speed and delay at the level of the entire network of roads and intersections on the island of Montreal. Also, a linear regression model is formulated to identify the geometric design and built environment characteristics affecting cyclist speeds on road segments. Among other results, on average, segment speeds are greater along arterials than on local streets and greater along segments with bicycle infrastructure than those without. Incorporating different measures of cyclist personality in the models revealed that the following characteristics all affect cyclist speeds along segments, each cyclist’s average speed on uphill, downhill and level segments as well as geometric design and built environment characteristics. The model results also identify that the factors that increase cyclist speeds along segments include, segments which have cyclists biking for work or school related purposes, segments used during morning peak and segments which do not have signalized intersections at either end.