Extending the gradient method to qualitative model reference adaptive control

The qualitative model reference adaptive control (QMRAC) system described is based on using fuzzy qualitative models to describe the physical system and the desired performance specification. This method allows accurate representation of the performance specification and knowledge of the physical system as an explicit model. Based on these explicit models an accurate solution is derived. In this work the extension of conventional MRAC methods, i.e. the gradient method, to a QMRAC system is discussed. The analytical properties of a QMRAC system makes it possible to asses the system performance, e.g. stability measure.