Modeling, design and altitude control of a four-rotor unmanned aerial vehicle

Four-rotor unmanned aerial vehicles (Quadrotor) are used in many areas such as safety, surveillance, targeting and tracking, which require dangerous, precise piloting. The dynamic structure of the aircraft provides a high thrust force to the system and makes it possible to carry out difficult movements. However, the nonlinear dynamic structure of the vehicle with four rotors is needed to drive each rotor in the four-rotor unmanned aerial vehicles due to reasons such as the necessity of speed control of motors. In this thesis, modeling and controller design for the attitude and altitude dynamics of quadrotor is aimed. Quadrotor mathematical modeling was done and a simulation model was created in Matlab / Simulink environment. Three different controllers have been designed, simulated and applied to the system for Quadrotor attitude and altitude controls. Firstly; Quadrotor attitude and altitude controls have been performed with Proportional-Derivative (PD) and Proportional-Integral-Derivative (PID) controllers. For this, the parameters of PD and PID controllers were designed and then tested on the quadrotor simulation model. Secondly; For the quadrotor attitude and altitude control, the Sliding Mode Controller (SMC) was designed and then tested on the quadrotor simulation model. Thirdly; The Backstepping Controller (BC) was designed and then tested to perform quadrotor attitude and altitude control on the simulation model. Quadrotor has been solid modeled in three dimensions in a computer environment and successful results have been obtained by testing on the physical model with the controller providing the best control over the simulation model..