scholarly journals Influence of Lane Policies on Freeway Traffic Mixed with Manual and Connected and Autonomous Vehicles

2020 ◽  
Vol 2020 ◽  
pp. 1-20
Author(s):  
Xuedong Hua ◽  
Weijie Yu ◽  
Wei Wang ◽  
Wenjie Xie
Keyword(s):  
Autonomous Vehicles ◽  
Traffic Management ◽  
Heterogeneous Traffic ◽  
Mixed Traffic ◽  
Freeway Traffic ◽  
Average Speed ◽  
Traffic Efficiency ◽  
Management Measures ◽  
Traffic Volumes ◽  
Ca Model

Connected and autonomous vehicles (CAVs) have become the highlights of traffic. Researchers in this field have proposed various traffic management measures to enhance the capacity and efficiency of traffic with CAVs, especially mixed traffic of CAVs and manual vehicles (MVs). Exclusive lane setting is included. However, exclusive lane policy-related researches for mixed traffic of CAVs and MVs were very limited, and the influence of number and location of exclusive lanes on the mixed traffic was unclear. To fill this gap, this paper aims to study the influence of different exclusive lane policies on mixed traffic and provide recommended lane policies under various traffic volumes and CAV penetration rates. Freeways with two lanes and three lanes in a single direction were taken into consideration, and sixteen lane policies were proposed. Then different lane policies were simulated with a new proposed cellular automata (CA) model, and properties including flux, average speed, and CAVs degradation were analyzed to evaluate the traffic efficiency of each lane policy. The results show that CAV exclusive lanes can improve the capacity, while MV exclusive lanes seem helpless for capacity improvement. Seven lane policies, including GC, GM, and CM for two-lane freeways and GCG, CGC, and CCM for three-lane freeways, outperform the others in terms of average speed. In addition, exclusive lanes can reduce the probability that CAVs degenerate to AVs. Our findings may help to optimize freeways’ lane policies and improve the efficiency of heterogeneous traffic mixed with CAVs and MVs.

scholarly journals Traffic Characteristics Evaluation and Traffic Management Measures: A Case study of Dharwad City

2018 ◽  
Vol 12 (1) ◽  
pp. 258-272 ◽  
Author(s):  
Devaraj Hanumappa ◽  
Raviraj H. Mulangi ◽  
Nityanand S. Kudachimath
Keyword(s):  
Urban Areas ◽  
Traffic Management ◽  
Multiple Constraints ◽  
Mixed Traffic ◽  
Traffic Characteristics ◽  
Road Users ◽  
Management Measures ◽  
The City ◽  
Planning Problems

Traffic problems in the urban areas are increasing at a rapid rate. Engineers, planners or the policymakers are having a tough time in dealing with their multiple constraints for getting the desired solution. Some of the main transportation planning problems are mixed traffic plying on the roads, inadequate parking areas, increasing number of vehicles and road users, the unbalanced pattern of land use with obsolete road system, increasing number of road facilities and environmental pollution. Since in India most of the cities are unplanned, we are only left with an option management of existing infrastructure. In this paper, one such case study is presented in which a detailed traffic management for the city of Dharwad is carried out.

Driver Behavior at a Freeway Merge to Mixed Traffic of Conventional and Connected Autonomous Vehicles

2020 ◽  
Vol 2674 (11) ◽  
pp. 867-874
Author(s):  
Sneha Chityala ◽  
John O. Sobanjo ◽  
Eren Erman Ozguven ◽  
Thobias Sando ◽  
Richard Twumasi-Boakye
Keyword(s):  
Autonomous Vehicles ◽  
Driving Simulator ◽  
The Elderly ◽  
Market Penetration ◽  
Mixed Traffic ◽  
Traffic Operations ◽  
Freeway Traffic ◽  
Elderly Drivers ◽  
Young Drivers ◽  
The Subject

Freeway merge ramps serve as one of the most challenging areas in traffic operations. This paper primarily focuses on creating a mixed traffic of conventional and connected/autonomous vehicles (CAVs) on freeways, and capturing driver behaviors both for the merging vehicle on the ramp and the freeway vehicles. The mixed distribution of vehicle headways of the freeway vehicles, developed based on various market penetration rates of the CAVs, was used to randomly generate vehicles through Monte Carlo simulation, and assigned as headways in a driving simulator. Based on perception, young drivers on the merge ramp were observed to choose critical headway gaps of 2.9 s, 1.8 s, and 1.7 s for freeway traffic of 0%, 50%, 75% penetration rates, respectively. For similar CAV penetration rates, the critical gaps observed for elderly drivers were 3.5 s, 2.0 s, and 1.9 s, respectively. When actually driving in the simulator, for the scenarios of 0% CAVs and 50% CAVs on the freeway, the values of average headway gaps accepted by young drivers were estimated as 2.36 s and 1.53 s, respectively. For the elderly drivers driving the simulator, the average headway gap values accepted were estimated as 2.72 s and 1.55 s, respectively, in the 0% and 50% penetration rates on the freeway traffic. Analyses of the speed profiles of the vehicles showed the effects of the acceleration/deceleration of merging vehicles, for both young and older drivers, on the freeway vehicles, including a few cases of collision. Overall, it was observed that the subject drivers accepted shorter headway gaps for increased CAV penetration levels.

Impact of Autonomous-Vehicle-Only Lanes in Mixed Traffic Conditions

2019 ◽  
Vol 2673 (9) ◽  
pp. 430-439 ◽  
Author(s):  
Hwapyeong Yu ◽  
Sehyun Tak ◽  
Minju Park ◽  
Hwasoo Yeo
Keyword(s):  
Autonomous Vehicles ◽  
Road Traffic ◽  
Positive Impact ◽  
Penetration Rate ◽  
Autonomous Vehicle ◽  
Market Penetration ◽  
Mixed Traffic ◽  
Negative Effects ◽  
Average Speed ◽  
Time To Collision

The introduction of autonomous vehicles (AVs) in the near future will have a significant impact on road traffic. AVs may have advantages in efficiency and convenience, but safety can be compromised in mixed operations of manual vehicles and AVs. To deal with the issues associated with mixed traffic and to avoid its negative effects, a special purpose lane reserved for AVs can be proposed to segregate AVs from manual vehicles. In this research, we analyze the effect on efficiency and safety of AVs in mixed traffic and in a situation where an AV-only lane is deployed. In the analysis, we investigate the average speed, the throughput, and the inverse time-to-collision (ITTC). We differentiate the behaviors of manual vehicles and AVs through the reaction time, desired speed, and car-following models. As a result, we observe that the efficiency is improved when the market penetration rate of AVs increases, especially when the highway throughput increases by up to 84% in the case of mixed traffic. However, safety worsens when the market penetration of AVs is under 40%. In this case, the average speed can be improved and the frequency of dangerous situations (ITTC > 0.49) can be reduced drastically in the merging section by making the innermost lane AV-only. Accordingly, we conclude that AV-only lanes can have a significant positive impact on efficiency and safety when the market penetration rate of AVs is low.

scholarly journals Feature Analysis on Mixed Traffic Flow of Manually Driven and Autonomous Vehicles Based on Cellular Automata

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Xinghua Hu ◽  
Mengyu Huang ◽  
Jianpu Guo
Keyword(s):  
Cellular Automata ◽  
Traffic Flow ◽  
Autonomous Vehicles ◽  
Theoretical Basis ◽  
Flow Model ◽  
Maximum Flow ◽  
Feature Analysis ◽  
Mixed Traffic ◽  
Mixed Traffic Flow ◽  
Ca Model

This paper attempts to disclose the features of the mixed traffic flow of manually driven vehicles (MVs) and autonomous vehicles (AVs). Considering dynamic headway, the mixed traffic flow was modelled based on the improved single-land cellular automata (CA) traffic flow model (DHD) proposed by Zhang Ningxi. The established CA model was adopted to obtain the maximum flow of the mixed traffic flow and was analyzed under different proportions of AVs. On this basis, the features of the mixed traffic flow were summarized. The main results are as follows: the proportion of AVs has a significant impact on the mixed traffic flow; when the proportion reached 0.6, the flow of the whole lane was twice that of the MV traffic flow. At a low density, the AV proportion has an obvious influence on mixed traffic flow. At a high density, the mixed traffic flow changed very little, as the AV proportion increased from 0 to 5. The reason is that the flow of the whole lane is constrained by the fact that MVs cannot move faster. However, when the AV proportion reached 0.8, the flow of the whole lane became three times that at the proportion of 0.6. At the speed of 126 km/h, the flow rate was 2.5 times the speed limit of 54 km/h. The findings lay a theoretical basis for the modelling of multilane mixed traffic flow.

Route guidance during evacuations integrated with perimeter control strategy in large-scale mixed traffic flow networks

2018 ◽  
Vol 29 (11) ◽  
pp. 1850112 ◽  
Author(s):  
Mianfang Liu ◽  
Dongchu Han ◽  
Dongmei Li ◽  
Ming Wang
Keyword(s):  
Traffic Flow ◽  
Control Strategy ◽  
Traffic Management ◽  
Large Scale ◽  
Route Choice ◽  
Heterogeneous Traffic ◽  
Route Guidance ◽  
Traffic Networks ◽  
Mixed Traffic ◽  
Mixed Flow

Recent efficient monitoring and traffic management of large-scale mixed traffic networks still remain a challenge for both traffic researchers and practitioners. The difficulty in modeling route guidance evacuation of pedestrian-vehicle mixed flow lies in mixed flow and uneven or heterogeneous network flow. Existing studies have demonstrated that multi-region control can display different layers of traffic state measurement and control, and incorporate heterogeneity effect in the large-scale network dynamics. The optimal perimeter control can manipulate the percentages of flows that transfer between two regions, offering real-time traffic management strategies to improve the network performance. However, the effect of route guidance evacuation integrated with perimeter control strategies in case of heterogeneous traffic networks is still unexplored. The paper advances in this direction by firstly extending route choice behavior aggregation with perimeter control. For an evacuation study, we consider a campus and its surrounding traffic network that can be classified into two types of networks: the first includes emergency areas that involve a large number of evacuees, and the second includes roads that lead to different destinations. The second network consists of some regions with different evacuation directions. Based on the configuration, this paper proposes a route evacuation guidance control strategy that addresses traffic flow first assignment between regions by controlling perimeter flow with the help of Macroscopic fundamental diagram (MFD) representation and to guide evacuates’ route choice at intersections by LOGIT model in regions. In addition, comparison results show that the proposed route guidance strategy has considerable potential to improve performances and equilibrium conditions (i.e. system optimum and user equilibrium) on the overall network.

Optimization of lane-changing advisory of connected and autonomous vehicles at a multi-lane work zone

2021 ◽  
pp. 2250020
Author(s):  
Wenjing Wu ◽  
Yongbin Zhan ◽  
Lili Yang ◽  
Renchao Sun ◽  
Anning Ni
Keyword(s):  
Autonomous Vehicles ◽  
Control Strategies ◽  
Autonomous Vehicle ◽  
Heterogeneous Traffic ◽  
Work Zone ◽  
Lane Changing ◽  
The Road ◽  
Traffic Efficiency ◽  
Traffic Distribution ◽  
Traffic Performance

The work zone with lane closure will be an active bottleneck due to vehicles’ mandatory lane-changing conflicts. The emerging Connected Autonomous Vehicle (CAV) technology provides opportunities for vehicle motion planning to improve traffic performance. However, the literature using CAV technology mainly focuses on single-lane lane-changing control in the merging area. The algorithm dealing with multi-lane lane-changing control is absent. In this paper, a simulation system with a lane-changing optimal strategy embedded for the multi-lane work zone is presented under the heterogeneous traffic flow. First, the road upstream of the work zone is divided into several segments, and an optimal multi-lane lane-changing algorithm is designed. It is recommended that CAVs, on the closure lane and the merged lane, change lanes on each segment to balance traffic distribution and minimize traffic delay. Second, to validate the algorithm proposed, a typical three-lane freeway with one-lane closed for the work zone is researched, and the simulation platform based on cellular automata is developed. Third, the advantages of multi-lane control strategies are studied and discussed in traffic efficiency improvement and collision risk reduction by comparing previous lane-changing control algorithms.

Pricing of Connected and Autonomous Vehicles in Mixed-Traffic Networks

2021 ◽  
pp. 036119812098585
Author(s):  
Paolo Delle Site
Keyword(s):  
Autonomous Vehicles ◽  
Marginal Cost ◽  
User Behavior ◽  
Social Planner ◽  
Traffic Networks ◽  
Mixed Traffic ◽  
The Third ◽  
First Case ◽  
Marginal Cost Pricing ◽  
The Social

For networks with human-driven vehicles (HDVs) only, pricing with arc-specific tolls has been proposed to achieve minimization of travel times in a decentralized way. However, the policy is hardly feasible from a technical viewpoint without connectivity. Therefore, for networks with mixed traffic of HDVs and connected and autonomous vehicles (CAVs), this paper considers pricing in a scenario where only CAVs are charged. In contrast to HDVs, CAVs can be managed as individual vehicles or as a fleet. In the latter case, CAVs can be routed to minimize the travel time of the fleet of CAVs or that of the entire fleet of HDVs and CAVs. We have a selfish user behavior in the first case, a private monopolist behavior in the second, a social planner behavior in the third. Pricing achieves in a decentralized way the social planner optimum. Tolls are not unique and can take both positive and negative values. Marginal cost pricing is one solution. The valid toll set is provided, and tolls are then computed according to two schemes: one with positive tolls only and minimum toll expenditure, and one with both tolls and subsidies and zero net expenditure. Convergent algorithms are used for the mixed-behavior equilibrium (simplicial decomposition algorithm) and toll determination (cutting plane algorithm). The computational experience with three networks: a two-arc network representative of the classic town bypass case, the Nguyen-Dupuis network, and the Anaheim network, provides useful policy insight.

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