ABSTRACT

There have been a number of contributions to the

problem of fuzzy control considering the linguistic

controllers developed by Mamdani [1]. That approach was limited in its further extension to the

topics of control theory--stability, optimal control,

robustness--because of the lack of an explicit

relation between the control theory and the fuzzy

look-up table. For a fast system like the hydraulic

position servo (HPS) system, making the fuzzy look-up table is very difficult. It is more difficult to make the fuzzy logic controller (FLC) to be robust when the piston stroke is changed.