A three-dimensional loading vehicle routing problem with split pickup and time windows

With the growth of e-commerce services, the number of boxes shipped through a logistics service provider (LSP) is increasing. Therefore, the loading of the boxes has to be done efficiently when designing the routes while taking into account the period of availability of the customers, i.e. their time windows. This work focuses on pickup operations, which has received less attention in the literature compared to the delivery, and which is subject to potential real-time changes, such as the arrival of new customers. These changes can be easily accommodated as the vehicle is initially empty and progressively filled up.
The problem under study is a vehicle routing problem with split pickup, time windows and three-dimensional loading constraints, namely, geometric, vertical stability, orientation, and reachability constraints.
In the first step, we have solved the static version of the problem, i.e. the problem where there is no uncertainty and all information is known at the beginning of the day. In the second step, we will address the dynamic version of the problem, meaning that routes are modified based on incoming information.