Abstract-Adaptive control algorithms are of interest in flight control systems design not only for their capability to improve performance and reliability but also for handling aerodynamic parameter uncertainties, external disturbances and modeling inaccuracies. In this paper, a direct adaptive sliding mode control is developed for the quadrotor attitude stabilization and altitude trajectory tracking. First, developed controller is applied without considering disturbances and parameter uncertainties. After, a centered white gaussian noise with some parameter uncertainties are added to the considered output vector, mass and inertia matrix, respectively. The synthesis of the adaptation laws is based on the positivity and Lyapunov design principle. Numerical simulations are performed showing the robustness of the proposed control technique.

A preliminary study on estimating aerodynamic forces of a Vertical/Short Takeoff and Landing (V/STOL) mini Unmanned Air Vehicle (UAV) configuration with Distributed Electric Propulsion (DEP) system is presented. The main objective is to offer the next generation fixed wing mini UAV aircraft configuration with high-speed cruise flight and vertical takeoff capabilities. The proposed concept uses four electric motors and propellers combination located on the leading edge of the wing. The described method uses semi-empirical formulations in order to estimate the forces and moments generated by the wing immersed in its distributed propeller slipstreams. Actuator disk theory is used for the propeller slipstream, where the thrust is assumed to be known for the calculations. Upwash of the fuselage and each propeller slipstream are taken into account for the wing and propeller inflow angle calculations. The resulting method, which is written as a program, serves as a conceptual design program for this type of configuration. Additionally, the program will be used for generating data for flight dynamics simulations. A candidate design is also presented, which is being manufactured for the ongoing developments and tests.

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