Research On Attitude Motion Control Of Quadrotor

The quadrotor is an excellent, novel vertical take-off and landing Unmanned Aerial Vehicle (UAV) for both military and civilian usages. It is also an important research direction of Mars Unmanned Air Vehicles. In recent years, the quadrotor has attracted great attention of researchers, and it is an international hot spot on the new study.This thesis investigate the attitude control of the three degrees of freedom (DOF) hovering system with quadrotor, simulates the four-rotor UAV, and constructs the indoor attitude control of the six degrees of freedom system with quadrotor. The quadrotor is an under-actuated dynamic rotorcraft with four input forces and six output coordinates. Quadrotor has four fixed pitch angle rotors, and both front-rear and left-right rotors turn in opposite directions and in varying rotor speeds. Quadrotor can change the lift forces, and therefore changes its attitude and position. The research contents are as follows.Firstly, the paper introduces the research background, technologies, important meanings and main control methods.Secondly, a nonlinear model of the system is established after researching the working principle and modeling method of the six DOF system, and simulating the six DOF system with quadrotor.Thirdly, according to the under-actuated model's characteristic, the system is designed on the basis of system channels, a fully-actuated channel and an under-actuated channel. A sliding mode controller based on exponential reaching law is designed.Finally, according to the under-actuated dynamic coupling of the system states, the under-actuated channel is designed into two sub-channels. The controller based on backstepping is designed, and its validity is proved by simulation in Matlab. In this paper, the method can guide the design of the actual flight controller.