Design of Control Systems to Hold Altitude and Heading in Severe Atmospheric Disturbances for an Unmanned Airplane

The objective of the present work is to design the control systems required to hold altitude and heading in severe atmospheric disturbances in cruise flight for the Unmanned Airplane for Ecological Conservation using modern control design techniques. The airplane mathematical model in open-loop was defined by the linearized longitudinal and lateraldirectional equations of motion. Different control systems were designed based on modern control design techniques. These are the eigenstructure assignment or polo-placement technique, linear quadratic design with full state feedback, and linear quadratic Gaussian design. To verify the design of control systems, simulations of the open-loop and closed-loop systems were performed, and each control system was tested. The atmospheric disturbances considered were the gust disturbance, which was idealized by the one-minus-cosine gust profile, and the atmospheric turbulence, which was modeled by Dryden’s function. The control systems designed to hold in-flight altitude and heading achieved their purpose. In any simulation, the maximum load factor, the stall speed and the maximum dive speed were not achieved.