Bearing signal separation enhancement with application to helicopter transmission system

Bearing vibration signal separation is essential for fault detection within gearboxes, signal separation is very challenging for non-stationary vibration signal, in addition, the vibration signal is susceptible to background noise and arduous signal transmission path from source to the receiver. Therefore, this research presents fault detection improvement through a series of vibration signal processing techniques based on signal separation, synchronous averaging SA and envelope analysis. These techniques have been tested experimentally using vibration data collected from the transmission system of a CS-29 ‘Category A’ helicopter gearbox under different bearing damage severity of the second planetary stage. Results showed successful improvement of bearing fault detection.