Same-day delivery with heterogeneous fleets of drones and vehicles

In this paper, we analyze how drones can be combined with regular delivery vehicles to improve same-day delivery performance. To this end, we present a dynamic vehicle routing problem with heterogeneous fleets. Customers order goods over the course of the day. These goods are delivered either by a drone or by a regular transportation vehicle within a delivery deadline. Drones are faster, but have a limited capacity as well as require charging after use. In the same-day context, vehicle capacity is not a constraint, but vehicles are slow due to urban traffic. To decide whether an order is delivered by a drone or by a vehicle, we present a policy function approximation based on geographical districting. Our computational study reveals two major implications. First, geographical districting is highly effective increasing the expected number of same-day deliveries. Second, a combination of drone and vehicle fleets may significantly reduce the required delivery resources.