In this thesis, a Takagi-Sugeno model for an Attitude/Altitude model of a quadrotor system is developed. With this Takagi-Sugeno model, a gain-scheduling state-feedback controller, as well as a state observer, have been designed for altitude and orientation control. Then, two different control schemes are analyzed in order to have a good performance on tracking changing references in the Attitude/Altitude control. Then an Integral Backstepping controller has been designed for the control of horizontal position. The stability of the whole control system has been studied, and finally the models and controllers have been tested in a simulation environment.