The impact of public drop‐off boxes and autonomous delivery robots in last‐mile delivery

Abstract The growing concern over emissions from last‐mile logistics is motivating the development of innovative delivery models aimed at reducing environmental impact and traffic congestion. To this end, we propose a last‐mile delivery scheme based on both public drop‐off boxes and autonomous delivery robots. Unlike current practices, we assume that parcels are primarily delivered by a fleet of traditional vehicles to a number of drop‐off boxes owned by the municipalities and shared by several logistics providers. Then, citizens must autonomously reach the drop‐off point to retrieve their parcels. An exception is made for a small group of customers (like, for instance, elderly or disabled people) whose parcels are loaded on autonomous delivery robots and home‐delivered, starting from the drop‐off points. To tackle this problem, we devise tailored destroy‐and‐repair operators to be embedded into a neighborhood‐search framework. We then conduct an extensive computational study on a set of realistic instances based on the urban area of Rome (Italy), aimed at assessing the benefits of the proposed last‐mile delivery infrastructure, compared to traditional distribution methods. Additionally, we evaluate the environmental and economic advantages of using autonomous delivery robots and drop‐off points.