In this comment Letter, we show that the stability analysis given in Ref. [1] cannot be extended to the fractional order (FO) uncertain Takagi–Sugeno (T–S) fuzzy model. In fact, the authors of Ref. [2] have investigated the stability analysis and synthesis of the FO uncertain T–S fuzzy systems. The proofs of Theorems 1 and 2 of Ref. [2] are based on the well-known analysis method in Ref. [1] for the following linear fractional order system:
$Dvx(t)=Ax(t)$
(1)
where 1 ≤ v ≤ 2. In Ref. [1], a necessary and sufficient condition for asymptotic stability of system (1) is given as a linear matrix inequality (LMI). It should be noted that this result must be applied only on linear time invariant (LTI) fractional order systems. The...

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