The Multi-Trip Vehicle Routing Problem with Time Windows and Release Dates

The multi-trip vehicle routing problem with time windows and release dates is a variant of the multi-trip vehicle routing problem where a time window and a release date are associated with each customer. The release date represents the date when the merchandise requested by a customer becomes available at the depot. The interest for this problem comes from the field of city logistics and the study of delivery systems involving City Distribution Centers (CDC). In these systems, goods are first delivered to a CDC before being transferred to eco-friendly vehicles for final delivery. We propose to address the problem through a population-based algorithm, with a giant tour representation for individuals. An efficient labeling procedure allows turning giant tours into solutions. Experiments demonstrate the effectiveness of the method.