An adaptive fuzzy-based tracking control equipped with VSS and H-infinity c
ontrol algorithms is proposed for nonlinear SISO systems involving plant un
certainties and external disturbances. Both well-defined VSS indirect and d
irect adaptive fuzzy-based H-infinity control schemes are developed. In ord
er to compensate the effect of the approximation error via the adaptive fuz
zy system an the H-infinity tracking control, a modified algebraic Riccati-
like equation must be solved and consequently it can be shown that all the
states and signals of the closed-loop system are bounded and the effect of
the external disturbance on the tracking error can be attenuated to any pre
scribed level. Compared with the precious literature that also addresses th
e adaptive fuzzy-based tracking control as in this paper, this paper can be
extended to handle a larger class of uncertain nonlinear systems by the in
corporation of robust VSS and H-infinity control techniques. Finally, simul
ation examples are included to confirm the validity and performance of the
proposed control algorithms.