Advances in vehicular communication technologies are expected to facilitate cooperative driving in the future. Connected and Automated Vehicles (CAVs) are able to collaboratively plan and execute driving maneuvers by sharing their perceptual knowledge and future plans. In this paper, we present an architecture for autonomous navigation of tight multi-lane platoons travelling on public roads. Using the proposed approach, CAVs are able to form single or multilane platoons of various geometrical configurations. They are able to reshape and adjust their configurations according to changes in the environment. The proposed architecture consists of three main components: an online decision-maker, an offline motion planner and an online path-follower. The decisionmaker selects the desired platoon configuration based on realtime information about the surrounding traffic. The motion planner uses an optimization-based approach for cooperative formation and reconfiguration in tight spaces. The motion planner uses a Model Predictive Control scheme to plan smooth, dynamically feasible and collision-free trajectories for all the vehicles within the platoon. The paper addresses online computation limitations by employing a family of maneuvers precomputed offline and stored on the vehicles' control units to be executed by a low-level path-following feedback controller in real-time based on the selected desired configuration. We demonstrate the effectiveness of our approach through simulations of three case studies: 1) formation reconfiguration 2) obstacle avoidance, and 3) benchmarking against behaviorbased planning in which the desired formation is achieved using a sequence of motion primitives. Videos and software can be found online here https://github.com/RoyaFiroozi/ Centralized-Planning.
I. INTRODUCTIONVehicular wireless communication systems including vehicle-to-vehicle (V2V) and vehicle to infrastructure (V2I) enhance cooperative driving by providing a communication network for information exchange between the vehicles to coordinate and plan conflict-free trajectories [1], [2]. Grouping multiple cooperative vehicles into single-lane or multi-lane formation is referred to as platooning. Using communication technologies, connected vehicles within the platoon can navigate in close proximity of each other, selforganize themselves to form certain configurations, keep tight formations and transit from one formation to another. Platooning improves traffic congestion, energy efficiency and safety [3], [4]. It increases road traffic throughput by allowing small inter-vehicle distances. Furthermore, moving with close spacing reduces aerodynamic drag and thus contributes to energy efficiency.Platooning in classical setting refers to a group of vehicles that form a road train in a single lane [5], [6].