Fractional Order Control of an Unmanned Aerial Vehicle (UAV)

Abstract

This paper deals with the trajectory control problem for a rotary-wing nonlinear vehicle model. The control of this kind of systems is one of the most challenging and attractive research areas. The design scheme presented is based on the use of fractional order controllers, originated from the application of the theory of Fractional Calculus to control system design. One of the interesting features of the control strategy proposed is the use of a fractional order derivative to ensure the robustness of the nonlinear system in spite of using a linearized design model. It is shown that by assuring constant phase margin on a frequency range around the roll-off frequencies the resulting control system is robust to parameter variations and nonlinear effects. With this strategy the control design problem becomes much simpler and gives very straightforward tuning rules. Fundamental operational principles are also considered for establishing the bandwidth of the input-output channels of the system. The performance of the controller is shown through nonlinear simulations.