Abstract
The issue of designing simultaneously robust and non-fragile observers for the classical integer-order systems has been widely investigated in the literature. Yet, there are just some few works that have tackled the same problem for non-integer-order systems. Moreover, the conformable derivative is an interesting concept that has been introduced by some researchers in the last decade. This new derivative presents some advantageous mathematical properties, compared with older concepts. In this paper, and motivated by these facts, the authors suggest a first scheme to design observers, which are simultaneously robust and non-fragile, for Lipschitz nonlinear conformable fractional-order systems. The H-infinity performance theory is used for that purpose. The efficiency of the developed approach is confirmed through simulations for a numerical example.