Vibration-Based Propeller Fault Diagnosis for Multicopters

We present a method for detecting faults in a multicopter's motor/propeller by analysis of the vibration spectrum as measured by an onboard accelerometer. Physical damage to a propeller causes additional vibration in the system during operation, and early detection of such faults may prevent further damage and potentially later catastrophic failure. In the proposed method, only a built-in accelerometer (as typically used by a multicopters flight computer) is used to provide vibration data of the vehicle, and no additional sensors are required. We exploit the fact that the motors rotate at different speeds during different phases of maneuvers, allowing a spectral analysis of measured vibrations to isolate a damaged motor. This method is shown to be effective at identifying multiple damaged propellers as well, and experimental results are presented to validate the concept.