Vehicle routing problem with deliveries and pickups: Modelling issues and meta-heuristics solution approaches

The paper investigates a class of extensions to the vehicle routing problem. Different

problem versions – some well-known, some more recent – are explained and placed in a

taxonomy. A central focus of the paper is on the assumptions generally made in the

literature and on the benefits of not making too restrictive assumptions. Research issues

on novel problem classes are highlighted. An Integer Linear Programming (ILP)

formulation is also presented. It is also shown how this formulation can be adapted to

cater for other problem versions. This paper also discusses various solution

methodologies including meta-heuristics to solve the models and what more is needed the

vehicle routing problem.