Revisiting the pallet loading problem using a discrete event system approach to minimise logistic costs

Abstract

This paper presents a new challenging modelling approach to support different heuristics to tackle the pallet loading problem (PLP). A discrete event system model to tackle the PLP is specified using the coloured Petri net formalism in order to integrate the model with the industrial context in which the PLP must be solved. New events can be formalised in the model to implement different heuristics to consider the upstream (production) and downstream (transport) influence of the palletising activity in the logistic flow. A state space analysis is performed to evaluate the different solutions to fit the maximum number of boxes on a rectangular pallet, supporting the inherent box diversity (heterogeneous palletising problems) of present production and distribution logistic systems. The heuristics implemented show that acceptable occupancy results can be obtained without requiring the exhaustive evaluation of the different feasible combination. The results demonstrate that it outperforms other approaches which have been suggested for this type of problem. Potentially useful extensions of the work are discussed.

Una revisión literaria del Problema de Carga del Pallet

“…On the other hand, existing software like CPLEX, LINDO and CPN Tools has also been employed in the research of a solution for the PLP in [1], [4], [5] and [37]. Table 1 was developed to summarize the technique used in each of the approaches reviewed.…”

“…However, in recent studies, as in the work of [4] and [26], simulation has proved to be useful to find proper solutions for it.…”

“…Some other studies like [1], [4] and [34] also consider a specific maximum height and / or weight, the demand of the customers for a specific product…”

“…For instance and in comparison with other process of the supply chain, the palletizing loading efficiency of any type of transport causes direct saving of the total logistics costs. These saving rank between 20-25% of the storage cost and up to 30 of the transportation costs [4], [7], [21] and [22].…”

“…The more efficiently the pallets are utilized, the less quantity of them are demanded to stack cargo. Beyond that, the impact of this activity on transportation and warehousing is evident as both costs are directly related to the use of space as well as the type of pallets and the quantity of them in the conformation of a shipment [4].…”