This paper develops a novel controller called adaptive iterative learning sliding mode (AILSM) to control linear and nonlinear incommensurate fractional-order systems. By definition of weighting parameter, the proposed controller can have both adaptive and iterative learning control structure in order to use the advantages of both controllers simultaneously and therefore, it achieves better control performance. This controller is designed in a way to be robust against the external disturbance. It also estimates unknown parameters of fractional-order systems. The proposed controller, unlike the conventional iterative learning control, does not need to apply direct control input to the output of the system and can also be implemented for incommensurate fractional-order systems. It is shown that the controller performs well for two cases. First, all state variables exist in output dynamic and second, only some of the state variables exist in the output dynamic. Illustrative examples verify the performance of the proposed control in presence of unknown disturbances and model uncertainties.

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