Uav Btt Control Technology

Unmanned Aerial Vehicle (UAV) has been developed in the direction of high-performance and all-purpose characteristics. A method of designing control system based on dynamic inversion (DI) and variable structure control (VSC) applied to Bank-To-Turn (BTT) UAV is proposed in this paper, which is ability to control high maneuver flight and robust to the parametric perturbation.Firstly, the UAV model is deduced based on the characteristic of UAV in the BTT mode, this model has high precision and it is simple. After deducing the model of BTT UAV, the control system is divided into two subsystems based on time-scale theory. In the fast-variable subsystem, rotational rates are considered to be outputs, calculated aerodynamic moments are considered to be inputs, then the actuator deflections are calculated based on calculated aerodynamic moments. In the slow-variable subsystem, dynamic angles are considered to be outputs, rotational rates are considered to be inputs. Then, DI is applied to two subsystems, the system employing DI has perfect dynamic characteristic, but the robustness is weak. The control system of BTT UAV must resist the uncertain of aerodynamic derivatives, so VSC is applied to prove the robustness. In the fast-variable subsystem, the Model Reference VSC law is designed based on calculated aerodynamic moments error; in the slow-variable subsystem, the Model Reference VSC law is designed based on calculated aerodynamic forces error, the principia of choosing parameter is proposed in this paper. The method requires bounds of aerodynamic derivatives, and it is easy and fit to engineering.Lastly, three channels united simulation with a UAV is tested considered to the dynamics of actuators. The control system works well in the command of step command, rectangular and sine wave, whose performance is accord with the requirement of UAV in the BTT mode and which is robust in the presence of large uncertain of aerodynamic derivatives. So the control system employing DI and VSC is effect applied to BTT UAV.