KNOWLEDGE REPRESENTATION USING FUZZY LOGIC BASED CHARACTERISTICS FOR SAFETY RELATED APPLICATIONS PART I: BASIC INVESTIGATIONS

摘要

Rule based systems for Fuzzy Control, Fuzzy Supervising and Fuzzy Diagnosis are non-linear multi-input, multi-output systems. The result of the signal processing within the system is a high dimensional characteristic field. For optimizing the behaviour of the system, a high number of free degrees is available. With this background, the paper describes the quality of a two dimensional Fuzzy Controller characteristic field in connection with the necessary deformation for the compensation of non-linear effects. It will be demonstrated that one should define two restrictions for the characteristic field: continuity without local extrema and differentiability. Under such conditions we need only two free degrees for optimizing the controller behaviour using the characteristic field deformation. With help of this experience, the high dimensional controller will be cascaded. A subjective decision for it is to distinguish the type of the input variables in dominant, non-dominant and optimization variables. The quality of the cascade is depending on the final characteristic field and the completeness of the rule base.