Real world optimisation problems require the rrtinimisation/maximisation of objectives that are often in conflict with one another. These problems (multi-objective optimisation problems, vector optimisation problems) are in general treated by using weighted sums or other decision-making schemes. An alternative way is to look for the Pareto optimal front. The authors modify the particle swarm algorithm to detect the Pareto optimal front. The proposed algorithm shows an excellent performance in minimising the number of solutions of the forward problem and also provides a very reliable representation of the Pareto optimal front.