Improving traffic flow at a 2-to-1 lane reduction with wirelessly connected, adaptive cruise control vehicles

Abstract

Wirelessly connected vehicles that exchange information about traffic conditions can reduce delays caused by congestion. At a 2-to-1 lane reduction, the improvement in flow past a bottleneck due to traffic with a random mixture of 40% connected vehicles is found to be 52%. Control is based on connected-vehicle-reported velocities near the bottleneck. In response to indications of congestion the connected vehicles, which are also adaptive cruise control vehicles, reduce their speed in slowdown regions. Early lane changes of manually driven vehicles from the terminated lane to the continuous lane are induced by the slowing connected vehicles. Selforganized congestion at the bottleneck is thus delayed or eliminated, depending upon the incoming flow magnitude. For the large majority of vehicles, travel times past the bottleneck are substantially reduced. Control is responsible for delaying the onset of congestion as the incoming flow increases. Adaptive cruise control increases the flow out of the congested state at the bottleneck. The nature of the congested state, when it occurs, appears to be similar under a variety of conditions. Typically 80-100 vehicles are approximately equally distributed between the lanes in the 500-m region prior to the end of the terminated lane. Without the adaptive cruise control capability, connected vehicles can delay the onset of congestion but do not increase the asymptotic flow past the bottleneck. Calculations are done using the Kerner-Klenov three-phase theory, stochastic discrete-time model for manual vehicles. The dynamics of the connected vehicles is given by a conventional adaptive cruise control algorithm plus commanded deceleration. Because time in the model for manual vehicles is discrete (one-second intervals), it is assumed that the acceleration of any vehicle immediately in front of a connected vehicle is constant during the time interval, thereby preserving the computational simplicity and speed of a discrete-time model.

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

“…In 2003, Bose and Ioannou [11] analyzed the flow densities of MVs and AVs and discussed the shock waves in the mixed traffic flow, using the car following model and the semiautomatic vehicle model. Davis [12] applied the car following model to simulate the traffic phenomena of the mixed traffic flow in the confluence area of the ramp, evaluated the local stability of traffic flow in the presence of AVs, and suggested AVs be provided with interconnected information, such as to debottleneck the traffic congestion on the reduced road. Kim and Liu [13] presented the concept of cooperative autonomous driving, which provides the drivers with the traffic situation ahead, enabling them to make better decisions that favor the efficiency and safety of traffic flow.…”

Characterization and control of a bottleneck-induced traffic-jam transition for self-propelled particles in a track

“…The triggering of jams is related to a wide variety of causes, such as obstacles and lane reduction [27][28][29], road crossings [30], or density fluctuations without bottlenecks [24,31]. However, the fundamental diagram systematically shows the increasing and decreasing regimes discussed above.…”

Controle do fluxo principal em autoestradas por meio de veículos cooperativos equipados com controle adaptativo de cruzeiro

“…Além disso, os limites de velocidade podem até mesmo ser impostos, contornando o problema de observância dos LVVs. De fato, várias técnicas que se bene-iciam de VACS, de sistemas cooperativos ou de integração veıćulo-infraestrutura (V2I -Vehicle-to-Infrastructure) foram propostos, tais como Hegyi et al (2013); Kattan et al (2015); Khondaker e Kattan (2015b); Roncoli et al (2015); Davis (2016); Grumert et al (2015); Müller et al (2016). Entretanto, desses trabalhos, apenas Müller et al (2016) adotou a abordagem CFP e nenhum deles considerou veıćulos equipados com controle adaptativo de cruzeiro (ACC -Adaptive Cruise Control) (Kesting et al, 2007).…”