*2.4. Fuzzy Logic Control*

Fuzzy logic makes it possible to give a nebulous and imprecise representation of the system. From the uncertain attributes, the fuzzy controller can provide decisions. It consists of a knowledge base which assembles the information of linguistic control rules. The fuzzy controller is made up of three parts, being the first part in charge of "fuzzifying" the inputs. At the entrance, it is mainly a question of affixing fuzzy membership functions by calling up membership values and association membership to the assigned entries. The second part is the inference system that is used with the knowledge base to create an inference following a reasoning process. The last part allows to "defuzzify", which implies the translation from fuzzy control fact to a real control decision for the system. In this work we use the fuzzy controller for the control of the HAPF. The synoptic diagram of the controller illustrated in Figure 5.

**Figure 5.** Synoptic diagram of the fuzzy controller.
