OICC Press Majlesi Journal of Electrical Engineering 2345-3796 9 2 2024 02 20 Adaptive Second Order Terminal Backstepping Sliding Mode for Attitude Control of Quadrotor with External Disturbances EN Alireza Modirrousta Department of Electrical Engineering, Hamedan University of Technology, Hamedan, Iran. Mahdi Khodabandeh Department of Electrical Engineering, Hamedan University of Technology, Hamedan, Iran. Journal Article 2024 02 20 This paper proposes a backstepping terminal sliding mode control with adaptive algorithm which applied to Quadrotor for free chattering, finite time convergence and robust aims. First of all, dynamic equation of a quadrotor has been obtained based on Euler-Lagrangian equations with considering additional disturbance and uncertainty. Furthermore, a nonlinear control scheme has been proposed to deal against defined perturbations. In the proposed control scheme, instead of using regular control input, the derivative of the control input has