Adaptive fuzzy global fast terminal sliding mode control of an over-actuated flying robot

Abstract

In this paper, the issue of full control (both position and orientation controls) of an over-actuated unmanned flying robot is addressed using an adaptive fuzzy global fast terminal sliding mode control (AF-GFTSMC) scheme in the presence of external disturbances and parametric uncertainties. At the first step, full dynamic equations of motion of a novel over-actuated flying robot are developed taking into account the rotational kinematics. Using the Lyapunov stability theorem, an AF-GFTSMC is designed to suppress the errors between desired references and actual responses of the robot in finite time. Since the number of actuators is more than control forces and torques, considering some constraints on actual control inputs, a control allocation strategy based on the reflective Newton algorithm is employed and formulated in order to compute the actual control inputs according to virtual control inputs. Finally, some simulations are performed in the presence of external disturbances and parametric uncertainties, utilizing different designed control strategies, classical and AF-GFTSMC methods. It is also clearly verified that the designed control approaches are effective and robust through tracking some predefined trajectory in 3D space as well as attenuation of chattering phenomena.