The Design And Attitute Control Of A Micro Quadrotor Aircraft

Micro Quadrotor is a kind of Unmanned Aerial Vehicle (UAV). Because of the simplestructure, highly maneuverable flight mode and the ability to design a vertical takeoff andlanding (VTOL), Micro Quadrotor is said to have a broad prospect in both military andcivilian usages. The Re numbers of a Micro Quadrotor is low as a reason to the small sizeand low flight speed. Besides, it’s also an under-actuated system with four actual controlinputs and six degrees of freedom (DOF). The aerodynamics with low Re number and theattitude control methods are both difficult and hot topics in recent research on MicroQuadrotor.In this paper, we concentrate on these two problems. The finite element model and thedynamic model of the Micro Quadrotor are built to study the aerodynamic characteristicsand attitude control methods, the results are verified by simulation tests. This paper has fivechapters with following contents:First of all, the dynamics and kinematics equations of the Quadrotor are establishedbased on classical mechanics and Newton’s Laws, then the equations are simplified byleading into four control parameters and ignoring the drag coefficient.Secondly, the three dimensional model of the Quadrotor body is built in UG based onthe real Quadrotor and the three dimensional physical model of the fluid fields wasestablished meshed in Ansys.Then the aerodynamic characteristics and vibration characteristics of the MicroQuadrotor aircraft are studied based on finite element method. By adding boundaryconditions, the fluid fields are analyzed numerically using the finite volume method and theaerodynamic characteristics were obtained. Then the aerodynamic force is loaded to theaircraft structure to get the stress distribution and find out where the maximum stress is. Atlast, the first six vibration modes and their vibration characteristics are obtained after themodal analysis of the micro quad-rotor aircraft.At last, a PID controller is designed for the upward flight mode. The feasibility of thecontrol method is verified by the digital simulation results. Besides, a Backsteppingcontroller is designed for the non-linear system. The control rates of the four channels areobtained by using Backstepping methods. The program is written in MATLAB and theresults show that the designed controller can achieve fixed hovering and trajectory tracking.