Analysis of Driver Response and Traffic Evolution under Variable Speed Limit Control

Over the past few decades, several active traffic control methods have been proposed to improve freeway efficiency at bottleneck locations. Variable speed limit (VSL) is one of these effective controls. Previous studies have evaluated VSL control, but primarily during recurrent congestion only. This study focuses on evaluating the performance of VSL control for both recurrent and non-recurrent congestion. To assess the effectiveness of a previously proposed VSL control in a real-world situation, this study has three evaluation objectives: (1) examine the control performance when recurrent and (or) non-recurrent congestion occurs; (2) assess the effectiveness of the control when a queue encounters the VSL sign; and (3) consider the impact of system detection delay in VSL control. Comparative experiments for Whitemud Drive in Edmonton, Alberta, Canada, are simulated in the VISSIM platform, and traffic performance is compared among scenarios with and without control. The simulation results show that VSL improves mobility for both recurrent and non-recurrent congestion. The VSL control reduces total travel time, and improves total travel distance and total flow. Furthermore, it slows down the shockwave propagation speed, improves the average speed on most of the freeway segments, and reduces the duration of traffic recovery.

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Exploring the impact of a coordinated variable speed limit control on congestion distribution in freeway

Journal of Traffic and Transportation Engineering (English Edition) ◽

10.1016/j.jtte.2015.03.005 ◽

2015 ◽

Vol 2 (3) ◽

pp. 167-178 ◽

Cited By ~ 6

Author(s):

Jing Cao ◽

Dawei Hu ◽

Ying Luo ◽

Tony Z. Qiu ◽

Zhuanglin Ma

Keyword(s):

Speed Limit ◽

Variable Speed ◽

Variable Speed Limit ◽

Variable Speed Limit Control ◽

The Impact

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Predicting Traffic Dynamics with Driver Response Model for Proactive Variable Speed Limit Control Algorithm

Mathematical Problems in Engineering ◽

10.1155/2018/6181756 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10

Author(s):

Huixuan Ye ◽

Lili Tu ◽

Jie Fang

Keyword(s):

Real Time ◽

Traffic Flow ◽

Control Algorithm ◽

Field Data ◽

Speed Limit ◽

Response Model ◽

Variable Speed ◽

Variable Speed Limit ◽

Driver Response ◽

Traffic State

Variable Speed Limit (VSL) control contributes to potential crash risk reduction by suggesting a suitable dynamic speed limit to achieve more stable and uniform traffic flow. In recent studies, researchers adopted macroscopic traffic flow models and perform prediction-based optimal VSL control. The response of drivers to the advised VSL is one of the most critical parameters in VSL-controlled speed dynamics modeling, which significantly affects the accuracy of traffic state prediction as well as the control reliability and performance. Nevertheless, the variations of driver responses were not explicitly modeled. Thus, in this research, the authors proposed a dynamic driver response model to formulate how the drivers respond to the advised VSL during various traffic conditions. The model was established and calibrated using field data to quantitatively analyze the dynamics of drivers’ desired speed regarding the advised VSL and current traffic state variables. A proactive VSL control algorithm incorporating the established driver response model was designed and implemented in field-data-based simulation study. The design proactive control algorithm modifies VSL in real-time according to the traffic state prediction results, aiming to reduce potential crash risks over the experiment site. By taking into account the real-time driver response variations, the VSL-controlled traffic state dynamics was more accurately predicted. The experimental results illustrated that the proposed control algorithm effectively reduces the crash probabilities in the traffic network.

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