Disturbance accomodation control for wind rejection of a quadcopter

This paper investigates the rejection of wind disturbances of an Unmanned Aerial Vehicle (UAV). UAVs are used for increasingly complex operations that require a great deal of accuracy and minimal position changes. This calls for better disturbance rejection. The drag-inclusive dynamics of a quadcopter are derived and used to create two uniaxial wind disturbance rejection controllers: a disturbance accommodating controller (DAC) and a nonlinear feedforward controller. Both controllers are integrated into an open-source flight controller. The performance of the controllers is assessed in simulation against the unmodified baseline. Over a 60 second loiter test, the DAC and nonlinear controllers result in a 45 % and 66 % decrease in error compared to the baseline respectively. Both controllers are shown to react to wind more rapidly. However, the DAC is found to be affected by changes in wind speed due to its linear nature. The baseline controller is used to show the feasibility of rejecting the effects of a 5 meters per second wind in a physical experiment.