US Patent 9828095 Motor deflection monitoring for unmanned aerial vehicles

Deflection of a rotor of a motor, such as a brushless motor, of an unmanned aerial vehicle (“UAV”) during operation may cause the magnets coupled to the interior surface of the rotor to move or walk down the surface, imbalancing the motor and potentially creating an unsafe flying condition for the UAV. The described methods and apparatus monitor rotor deflection of the motor during operation and alter one or more flight characteristics of the UAV if the deflection exceeds a tolerance range. By altering flight characteristics, external forces acting on the motor may be reduced, thereby reducing the deflection of the rotor.