Application of instantaneous frequency extraction based on continuous wavelet transform in velocity measurement of photoelectric encoder
Jing Li, Nan Wang · 2018
A new velocity measurement of photoelectrical encoder was proposed.According to the progressive characteristics of the high-frequency components in the angle error signal of the encoder, the velocity of rotation information was extracted by processing and analyzing the measured angle error.Continuous wavelet transform as a powerful non-stationary signal analysis tool is used for extracting the features of angle error components.Based on the continuous wavelet transform, a wavelet ridge extraction method, called iterative algorithm, was carried out for the instantaneous frequency estimation.The effectiveness of the proposed method has been validated by the experimental data.The results demonstrated that the high-frequency components of the angle error, after proper processing by time-frequency analysis techniques, can be effectively used for velocity measurement of the photoelectric encoder.This method can effectively reduce the influence of noise and interference on the measurement accuracy.