Multi-rotor eVTOL Flight Simulation and Assessment under Atmospheric Turbulence

Atmospheric turbulence is applied to a 1200 lb quadcopter to evaluate the aircraft’s rigid body response together with the rotor speed and motor current responses. Turbulence is generated using TurbSim to produce a full-field flow which is convected downstream over the aircraft. Three levels of turbulence intensity (mild, moderate, and severe) are applied to the aircraft, with the increasing levels of turbulence corresponding to higher velocity fluctuation in the flow-field. An outer loop flight controller, tuned to meet Level 1 handling qualities, is used to reject the disturbances to the aircraft airspeed. Various levels of turbulence produce larger aircraft response, with the severe case producing the largest peak-to-peak values for rigid body, rotor speed, and motor current response (4.74, 114 RPM, and 160A, respectively). While the severe turbulence case is the most demanding on the motors, it is less than what has been previously seen for typical maneuvers. Therefore, motor size is limited by aircraft maneuver constraint, given the turbulence cases considered.