Feedback control algorithms for the dissipation of traffic waves with autonomous vehicles

International audienceThis article considers the problem of traffic control in which an autonomous vehicle is used to regulate human piloted traffic to dissipate stop and go traffic waves. We first investigate the controllability of well-known microscopic traffic flow models, namely i) the Bando model (also known as the optimal velocity model), ii) the follow-the-leader model, and iii) a combined optimal velocity follow the leader model. Based on the controllability results, we propose three control strategies for an autonomous vehicle to stabilize the other, human-piloted traffic. We subsequently simulate the control effects on the microscopic models of human drivers in numerical experiments to quantify the potential benefits of the controllers. Based on the simulations, finally we conduct a field experiment with 22 human drivers and a fully autonomous-capable vehicle, to assess the feasibility of autonomous vehicle based traffic control on real human piloted traffic. We show that both in simulation and in the field test that an autonomous vehicle is able to dampen waves generated by 22 cars, and that as a consequence, the total fuel consumption of all vehicles is reduced by up to 20%

Emergent micro-communities for ride-sharing enabled Mobility-on-Demand systems

International audienceMobility-on-Demand (MoD) systems offer a flexible mobility alternative to classical public transportation services in urban areas. However, a significant part of MoD vehicles operating time can be spent waiting empty or driving to reach new potential ride requests. Improving vehicle fleet operation is an extremely challenging problem, as the number of vehicles in operation at a time cannot be controlled. To cope with this issue, new forms of mobility are being deployed successfully: for instance, ride-sharing enabled MoD systems can match riders from several requests. Existing work considers that the best way to achieve significant performance is to control vehicles. However, travel times are hard to predict in congested traffic, and optimizing a relocation scheme of empty vehicles can be hard for large-scale networks and big fleets. In this paper, we take the perspective of riders that collaborate with other travellers in order to walk to locations where they are more likely to get picked up by a MoD system. We introduce a multi-agent model that accounts for vehicles, riders and the MoD platform. The aim of this interaction-based model is to enable riders to dynamically form emergent micro-communities that physically meet, wait and share a vehicle together for part of their trip. Our approach is evaluated in a simulation framework that allows to investigate the respective behaviour of vehicles and riders. Ride requests are generated from New York City taxi dataset. We show that our approach allows riders to improve their chance to be picked up and reduce their travel costs while improving overall efficiency of the fleet

Early Western Mediterranean Impressed Wares (Early 6th millennium BCE): new interdisciplinary research on pottery paste processing at Pendimoun rock-shelter (Alpes-Maritimes, France)

International audienceEarly Western Mediterranean Impressed Wares (Early 6th millennium BCE): new interdisciplinary research on pottery paste processing at Pendimoun rock-shelter (Alpes-Maritimes, France

Early Western Mediterranean Impressed Wares (Early 6th millennium BCE): new interdisciplinary research on pottery paste processing at Pendimoun rock-shelter (Alpes-Maritimes, France)

International audienceEarly Western Mediterranean Impressed Wares (Early 6th millennium BCE): new interdisciplinary research on pottery paste processing at Pendimoun rock-shelter (Alpes-Maritimes, France

GRAVITY: Microarcsecond astrometry and deep interfereometric imaging with the VLTI

International audienc

GRAVITY: Microarcsecond astrometry and deep interfereometric imaging with the VLTI

International audienc

Science with GRAVITY, the NIR Interferometric Imager

International audienc

Science with GRAVITY, the NIR Interferometric Imager

International audienc