简介：Inordertoprovidethebasisforparameterselectionofvocaldiseasesclassification,anonlineardynamicmodelingmethodisproposed.Abiomechanicalmodelofvocalcordswithpolyporparalysis,whichcouplestoglottalairflowtoproducelaryngealsoundsource,isintroduced.Andthenthefundamentalfrequencyanditsperturbationparametersaresolved.Poincaresectionandbifurcationdiagramareappliedtononlinearanalysisofmodelvibration.Bychangingthepathologicalparametersorsubglottalpressure,thechangesoffundamentalfrequencyandLyapunovexponentsareanalyzed.Thesimulationresultsshowthat,vocalcordparalysisreducesthefundamentalfrequency,andthechaosoccursonlywithinacertainpressurerange;whilevocalcordwithapolypdon’treducethefundamentalfrequency,chaosdistributesthroughouttheentirerangeofpressure.Thereforethisstudyishelpfulforclassificationofpolypandparalysisbytheacousticdiagnoses.