The Pickup and Delivery Problem with Crossdock for Perishable Goods

Our work departs from the original definition of the Pickup and Delivery Problem (PDP) and extends it by considering an interchange point (crossdock) where vehicles can exchange their goods with other vehicles in order to shorten their delivery routes and reduce their running times. Multiple operational constraints, such as time windows, vehicle capacities, and the synchronization of vehicles at the crossdock, are considered. In addition, the specific requirements of perishable goods, which should not be carried on long trips, are taken into account. Given this consideration, this study introduces the Pickup and Delivery Problem with Crossdock for Perishable Goods (PDPCDPG) and models it as a nonlinear programming problem. PDPCDPG is then reformulated to a MILP with the use of linearizations and its search space is tightened with the addition of valid inequalities that are employed when solving the problem to global optimality with Branch-and-Cut. Various computational experiments are conducted on benchmark instances found in the literature to assess the performance of our model. The results demonstrate the solution stability of the proposed approach. The proposed model aims to provide a practical and effective approach for transportation and logistics companies dealing with time-sensitive deliveries.