المستخلص: |
Due to the increasing demand on the autonomy level in the flied of unmanned aircraft system (UAS), the Autonomous control of unmanned aircraft system (AUAS) has been becoming of great importance and interest among many researchers. The controller for such systems can either be classical controller or intelligent controller. This paper concentrates on studying the possibility of integrating the intelligent controller with the PID controller to control the speed and altitude of an aircraft and to perform the longitudinal control (takeoff and altitude control) of unmanned aircraft autonomously. A hybrid control can be a combination of different control techniques, in this paper, PID control, model predictive control (MPC) and neural network control. The proposed longitudinal controller included three autopilots: the speed control autopilot and it has been designed using PID technique, while the pitch orientation autopilot, has been designed using PID technique for the low angles of attack and MPC method for the high angles of attack, and the altitude control autopilot. The hybrid intelligent longitudinal controller was simulated and tested successfully. The PID controller has shown a significant response in compensating the errors that are related to the control surface actuators, while the neural controller was very robust in the control of the overall response of the system. The aircraft's actual takeoff trajectory was very acceptable, compared to the desired takeoff trajectory, with the ability of aborting the takeoff in case of insufficient takeoff condition.
|