Optimal orientation for automated vehicles on large lane-free roundaboutsOptimal orientation for automated vehicles on large lane-free roundabouts Πλήρης Δημοσίευση σε Συνέδριο Conference Full Paper 2024-06-272023enPath planning for vehicles on large, complex, lane-free roundabouts is challenging due to the geometrical features and frequent conflicts among entering, navigating, and exiting vehicles. A key difficulty is to properly determine the desired vehicle orientations on the roundabout so that vehicles enter the roundabout and move towards their corresponding exits smoothly and safely. Specification of vehicle orientations should consider the resulting trip distance, the angle difference from other vehicles, and the exploitation of the available roundabout surface for efficient traffic flow. This paper proposes an optimal control approach to determine optimal vehicle orientations at each point on the roundabout, in dependence of the exit branch, so as to minimize a weighted sum of the trip distance and the deviation from the circular motion. Analytical solutions for two extreme cases, addressing only the shortest path or only the minimum deviation from the circular angle, respectively, are derived. For the general weighted problem solution, a Dynamic Programming-based (backward Dijkstra) algorithm is employed to deliver the optimal orientations in a 2-D space-discretized grid of the roundabout surface. In the light of the optimal solution, a computationally light near-optimal approach is also proposed. As a challenging case study, the methods are applied to the famous roundabout of Place Charles de Gaulle in Paris, which features a road width of 38 m and comprises 12 bidirectional radial streets, hence a total of 144 origin-destination movements for the vehicles.The research leading to these results has received funding from the European Research Council under the European Union’s Horizon 2020 Research and Innovation programme/ ERC Grant Agreement n. [833915], project TrafficFluid.http://creativecommons.org/licenses/by-nc-nd/4.0/62nd IEEE Conference on Decision and ControlProc. 62nd IEEE Conference on Decision and ControlNaderi_et_al_CDC 2023_manuscript.pdfChania [Greece]Library of TUC2024-06-24application/pdf755.8 kBfree Naderi Mahdi Naderi Mahdi Mavroeidi Maria-Konstantina Μαυροειδη Μαρια-Κωνσταντινα Papamichail Ioannis Παπαμιχαηλ Ιωαννης Papageorgiou Markos Παπαγεωργιου Μαρκος Institute of Electrical and Electronics Engineers Automated vehicles Lane-free traffic Lane-free roundabout