In order to overcome the shortages of Hilbert-Huang transform(HHT)

an improved HHT was proposed by the energy analysis method based on the singularity value decomposition of the track matrix reconstructed by time series

and a method for judging the pseudo-IMFs by empirical mode decomposition(EMD) was also presented.The advantages of improved HHT were verified from simulation signals.Then

the improved HHT was applied to detect the slight rubbing simulation of dual-rotor aero engine.The simulation results were compared with previous HHT and wavelet transform

respectively

showing that the improved HHT has the advantage of separating efficiently the weak component of signals from other strong components

and also confirming the slight rubbing more easily.The analytical results provide a useful reference for diagnosing the fault of rubbing.