A Beautiful Fleet: Optimal Repositioning in E-scooter Sharing Systems for Urban Decorum

In recent years, many electric scooters (e-scooters) sharing companies have appeared around the world. However, a major issue that has soon become apparent is that a consistent part of the users is prone to park the e-scooters without caring about the rules of the road, abandoning them in locations and positions that greatly reduce urban decorum and may interfere with pedestrians and other vehicles. To cope with the issue of bad parking and to not compromise acceptance of e-scooters by city residents, some sharing companies have started to include correcting the position of wrongly parked scooters as an important part of their operations. In this work, we address the problem of optimally managing the actions of a set of agents who are hired by a sharing company expressly for repositioning e-scooters in order to guarantee urban decorum. We call these agents beautificators, since their fundamental task is to reposition scooters over short distances (even just a few meters), so to fix inappropriate and disordered parking made by users. We stress that such repositioning must not be confounded with traditional relocation made in vehicle-sharing systems to rebalance fleets in the service area: rebalancing is made over medium and long city distances and is primarily aimed at guaranteeing a balanced distribution of vehicles in the service area, better satisfying the demand and increasing the overall profit. To the best of our knowledge, such optimization problem has not yet been considered in literature and we propose to model it by Integer Linear Programming and solve it by means of a matheuristic, which offers a good performance on realistic data instances defined in collaboration with e-scooter sharing professionals.