A Study of Controlling a Tricopter

Abstract

The objective of this dissertation is about the study on controlling a three rotor helicopter or a tricopter. The tricopter is an aircraft with two fixed rotors and one tilting rotor. In this dissertation, the following three problems are considered. The first one is the kinematic and dynamic modellings of a tricopter. The second is control algorithm. The last one is hardware development. First, the kinematic and dynamic modellings of the tricopter are presented to understand its behavior. The Newton-Euler formula and the Euler angles theories are used to provide the modellings information with physics and mathematical derivatives. The dynamic modelling is linearized to reduce its complexity. The outputs chosen are the Euler angles (attitude or orientation) and the height (attitude) of the tricopter. Second, a controller to control the altitude and attitude separately is proposed. From the linearized dynamic model and the control strategy, a tracking controller is designed using the backstepping control algorithm. The objective of the controller is to make the outputs converge to the references inputs. Third, to implement the proposed tracking controller, a real tricopter platform is developed with several interconnected devices such as: motors, sensors, Micro Control Unit (MCU), etc. The sensors are used for measuring the aircraft attitude and its height from the ground. The sensors’ data and the control algorithm are computed by the Micro Control Unit (MCU) which provides the signals to the motors. Finally, simulation results are done to demonstrate the effectiveness of the proposed controller. Keywords: Aero Dynamic, Unmanned Aerial Vehicles (UAVs), Vertical Take Off and Land (VTOL), Backstepping Control