Optimal Control Designing for a Discrete Model of Helicopter in Hover

The use of autonomous vehicles, have been increased during the last years. An autonomous helicopter has advantages in maneuverability and vertical flight compared to autonomous airplane which is not able to hover. In addition, the ability to take off and land in a limited space is clear advantages for autonomous helicopter. In this paper, the stabilization problem of the helicopter in hover using optimal control is investigated. At first, a nonlinear model for helicopter is developed, and then the model is linearized to obtain a linear model. Using this linear model, a controller based on linear quadratic regulator (LQR) has been designed. Since all states are not measurable, KALMAN observer then has been added to the model. Finally, the performance of the controller is tested on the nonlinear model. The simulation results show that the controller is able to stabilize the system when separate initial state values are non-zero, it can be concluded that the controller shows satisfactory performance.