In this paper, a stable direct adaptive general type-2 fuzzy logic controller (DAG2FLC) is introduced for a class of nonlinear systems. The proposed controller uses advantage of general type-2 fuzzy logic systems (GT2FLS) in handling dynamic uncertainties to approximate unknown nonlinear actions. Implementing general type-2 fuzzy systems is computationally costly; however, by using a recently introduced plane representation, a GT2FLS can be seen as composition of several interval type-2 fuzzy logic systems (IT2FLS) with a corresponding level of α for each. Linguistic rules are directly incorporated into the DAG2FLC controller and in addition, a H^∞ compensator is corrupted to attenuate external disturbance and fuzzy approximation error. Also general type-2 fuzzy adaptation laws are derived using Lyapunov approach, and the stability of the closed loop system has been proven by mathematical analysis. In order to evaluate the performance of the proposed controller, the results are compared with those obtained by direct adaptive type-1 fuzzy logic controller (DAT1FLC) and a direct adaptive interval type-2 fuzzy logic controller (DAIT2FLC), which are the latest researches in the problem in hand. The proposed controller is applied to a chaotic Gyro system as a case study. Simulation reveals the effectiveness of the proposed controller in presence of dynamic uncertainties and external disturbances.

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