To highlight the change characteristics of surface electromyography(sEMG)signal during muscle fatigue

a single-component muscle fatigue modal extraction method of sEMG singals based on adaptive Chirp modal decomposition(ACMD)method is proposed.A prior knowledge of the target mode is preset

and the instantaneous frequency(IF)extraction method based on the normalization operation of the signal derivative is improved

and the single-component muscle fatigue modal signal can be extracted independently after ACMD decomposition.This method is not affected by time-frequency resolution and has high computational efficiency.By quantitative analysis of muscle fatigue

comparisons are made with the original sEMG signal and the component decomposed by variational mode decomposition(VMD).The results show that the single component muscle fatigue mode extracted by this method has better ability to distinguish fatigue degree and anti-interference ability.