On the role of fuzzy logic in production planning

Production planning means, within a company, essentially the sorting of some products with respect to their "importance". This identifies the few strategic products and helps the management to plan the production process. Usually, for simplicity, only one importance criterion is taken into account. We introduce a fuzzy logic based method for weighing importance criteria against one another. Similar to Pareto's rule, we use fuzzy rules for ordering the products under each criterion, then we show how these local orderings can be integrated into a new total ordering. We introduce the use of hedges in the fuzzy rule base responsible for this integration. The integration requires a novel defuzzification method that we illustrate with an example from the automotive industry.