Study on Chaos-Based Weak Signal Detection Method with Duffing Oscillator

Abstract

Aiming at the feature extraction of weak periodic signal in early fault of machinery, a novel weak periodic signal detection with Duffing oscillator based on empirical modedecomposition (EMD) was presented. The chaotic character of Duffing oscillator was analyzed, and the Melnikov method of determining chaotic threshold of Duffing oscillators was discussed. The principle of weak signal detection based on the change of phase trace was described. In practical engineering measurement, the influence of noise to the system status in the chaos detection process was studied. EMD was proposed to avoid component interference, and weak characteristic signal can be separated from background signal and noise. The analysis results show that the weak periodic signal can be detected efficiently.KeywordsDuffing oscillatorchaosempirical mode decompositionweak signal detection