The paper introduces, a novel fractional-order robust controller based on fractional-order terminal sliding mode control technique for stabilization of a class of uncertain chaotic systems in the presence of structured uncertainties and external disturbances. First, applying fractional calculus, a fractional-order terminal sliding surface is proposed and then to satisfy the sliding condition in finite time, the corresponding control law is designed using Lyapunov stability theorem. The proposed fractional-order robust controller exhibits superior robust performance, guaranties finite-time convergence and stability of the closed-loop control system, eliminates the undesirable chattering phenomenon, and repress chaotic behaviors, completely. Finally, the effectiveness of the proposed controller is illustrated through the several numerical simulations.

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