“…e presentation of a nonlinear system with the noninteger derivative is named fractional-order system (FOS). ere are many applications of FOSs on real-world fields, whether in signal processing, chemistry, electricity, thermal, or control theory, for example, observer design [1][2][3], finite-time stability [4], fault estimation [5], and asymptotic stability [6][7][8]. In fact, with regard to observer design, authors in [1] presented a fractional-order observer design for fractionalorder nonlinear systems.…”