Based On Multi-sensor Information Fusion Of UAV Flight Control System Design

Quad-Rotor is different from other unmanned aerial vehicle(UAV) characteristics such as vertical take-off and landing(VTOL), autonomous hovering, and inverted flight. It can easily enter the narrow space where fixed wing unmanned plane can not enter into and achieve the goal of aerial photography, real-time monitoring, hidden investigation and auxiliary hostage rescue missions. Those advantages making it become the current focus of the UAV research.Quad-Rotor can't be equipped with high precision sensors for attitude measurement because of the limitations with its weight, loading and size. Thus it is important to obtain high precision attitude information. In addition, due to the Quad- Rotor is often in a low and narrow space flight, it has been disturbed with the external environmental factors,so the research of flight control system is also significant. According to the problems mentioned above, the system mainly do the following research work.Through deeply analyzing the two methods of attitude algorithm of Quad- Rotor and its characteristics, designing a multi-sensor fusion estimation algorithm aimed at the low accuracy of attitude algorithm data, the lack of redundancy control and easy to diverge, in order to solving the Quad-Rotor profile.In order to optimize the flight stability and the robustness of Quad-Rotor system. Based on the Quad-Rotor system model, through combining the modern control theory with the traditional control methodology, an angular velocity of the inner LQR(linear quadratic optimal) control method is set up,it has the advantages which can improve the dynamic characteristics of the inner loop and the steady state performance. And outer angle loop PID control of double closed loop controller is built, it is easy to master and have the low accuracy requirement of model. By taking the full advantages of the above mentioned, to achieve the flight control of Quad-Rotor.Finally, the Quad-Rotor test platform is built. Tests are carried out with the aim of the attitude calculation and flight control, and the corresponding experimental data is given. The experimental results show that the design of the attitude estimation algorithm is rapid and efficient, LQR&PID controller can realize stable flight of Quad-Rotor.