Simulational analysis of two controllers for variable speed limit control

Abstract

Variable speed limit control (VSLC) is one of the services from the domain of intelligent transport systems applied to alleviate or prevent congestion on urban motorways. The main idea of VSLC is to change the speed limit according to current traffic or weather in order to improve the traffic situation. Improvement of the traffic situation on urban motorways depends on the applied controller and its parameters. For this reason, the controllers chosen for implementation have to be tested in simulations using a realistic urban motorway segment, placement of sensors and traffic scenario, and a relevant set of control parameters. An analysis of two VSLC controllers, including the influence of their parameters on controller performance with respect to traffic and environmental aspects, is presented in this paper. To this end, an appropriate microscopic simulation framework was developed, the fundamental diagram of a simulated synthetic urban motorway segment was measured and traffic parameters, with vehicle emissions values, were obtained. The effectiveness of the two analysed controllers was compared based on the obtained simulation results. The results revealed that appropriate settings of the controller are crucial to ensure optimal use of urban motorways with minimum travel times and vehicle emissions.

Influence of Spatial Placement of Variable Speed Limit Zones on Urban Motorway Traffic Control

“…As mentioned, in this section, we describe the methodology used in our experiment in detail regarding the impact of different VSL and acceleration zone lengths on VSL efficiency. We conducted our experiment using the SPSC-VSL controller [8,9]. The main hypothesis about influence of different VSL zones and their acceleration part was analysed in [6].…”

“…In our previous work [8], we implemented and tested the Simple Proportional Speed Limit Controller for VSL control (SPSC-VSL) originally proposed in [9]. It should be noted that in the modelling described in [9] and [8] the authors did not elaborate the effect of different VSL configurations on SPSC-VSL performance.…”

“…In our previous work [8], we implemented and tested the Simple Proportional Speed Limit Controller for VSL control (SPSC-VSL) originally proposed in [9]. It should be noted that in the modelling described in [9] and [8] the authors did not elaborate the effect of different VSL configurations on SPSC-VSL performance. Analysis in [6] shows the existence of strong correlation between different VSL zones configurations (speed limit zone length and its distance from the bottleneck location) and VSL efficiency.…”

Variable Speed Limit Strategies Based on the Macro Hierarchical Control Traffic Flow Model

“…Besides the direct application of VSL on traffic system, it is also introduced into micro-and mesotraffic flow model [17,18] and other optimization models [19][20][21][22]. Abdel et al used microscopic simulation models to analyze the effects of different speed limit strategies on alleviating and improving road safety [17].…”

“…Abdel et al used microscopic simulation models to analyze the effects of different speed limit strategies on alleviating and improving road safety [17]. Inanjko established a microscopic simulation framework to analyze the layout and application scenarios of the VSL controller using travel time and vehicle emissions as indicators [18]. Fang proposed a VSL control algorithm based on the model predictive control (MPC) framework.…”