Using qualitative bond graph reasoning to derive look-up tables for fuzzy logic controllers

Qualitative reasoning, bond graphs and fuzzy logic are developed respectively in three different fields: computer science, system dynamics and automatic control. They all have their own strengths and weaknesses. Fortunately, these methods are compensating and they can be used to offset each other´s weaknesses. Qualitative reasoning on bond graphs leads to ambiguities in its reasoning process while these ambiguities can be resolved by self-organising fuzzy logic through employing the system identification approach to articulate models. On the other hand, fuzzy logic treats a system as a black box and does not use any structural information, while qualitative reasoning on bond graphs contains this information and can be used to systematically derive look-up tables in fuzzy logic. The paper presents a method of using structural information to generate look-up tables, which will then be used for fuzzy logic control. An example is analysed to explain the concepts