Fast Terminal Sliding-Mode Control with an Integral Filter Applied to a Longitudinal Axis of Flying Vehicles

The automatic pilot flight control system is undoubtedly one of the most important parts of the flying vehicle that provide stability and to operate appropriately in the guidance section. Considering to nonlinear, dynamic and time-varying system, structural and parametric uncertainties of the flying vehicles, in flight control, varietal control approach have to achieve stability, proper operation as well as decreasing effect of uncertainties and modeling errors. In this paper, designing of the longitudinal flying vehicles autopilot a Fast Terminal Sliding Mode Control (FTSMC). Variable structure systems because of the robustness effect on uncertainty and the effects on disturbances which a contributor to widespread efficiency. One of the methods for controlling the variable structure is a sliding mode, which is one of the nonlinear controllers that can control the system in the structured uncertainties and unstructured uncertainties. Additionally, in the method of classic sliding Mode Control is got convergence of states equilibrium point by an asymptotic curve. While proportional Integral Sliding Mode Control has the convergence of states to the equilibrium point in finite time. One of the issues is that finite time cannot determine the time of convergence when the state turn initial position to a final position. The proposed method is based on the Lyapunov stability theory and has guaranteed stability of the control system. The controller is robust to external disturbances and unmodified dynamics. Three types of controllers which are multi-input-multi-output (MIMO) system with random uncertainty are designed. Furthermore, the classic sliding mode controller, the proportional-integral sliding mode controller as well as the integral terminal sliding mode controller are reviewed. A glance at the results simulates shows an improved in the proposed method. Simulations are done using MATLAB software.