DPCM-based vibration sensor data compression and its effect on structural system identification

(整期优先)网络出版时间:2005-01-11
/ 1
Duetothelargescaleandcomplexityofcivilinfrastructures,structuralhealthmonitoringtypicallyrequiresasubstantialnumberofsensors,whichconsequentlygeneratehugevolumesofsensordata.Innovativesensordatacompressiontechniquesarehighlydesiredtofacilitateefficientdatastorageandremoteretrievalofsensordata.ThispaperpresentsavibrationsensordatacompressionalgorithmbasedontheDifferentialPulseCodeModulation(DPCM)methodandtheconsiderationofeffectsofsignaldistortionduetolossydatacompressiononstructuralsystemidentification.TheDPCMsystemconcernedconsistsoftwoprimarycomponents:linearpredictorandquantizer.FortheDPCMsystemconsideredinthisstudy,theLeastSquaremethodisusedtoderivethelinearpredictorcoefficientsandJayantquantizerisusedforscalarquantization.A5-DOFmodelstructureisusedastheprototypestructureinnumericalstudy.NumericalsimulationwascarriedouttostudytheperformanceoftheproposedDPCM-baseddatacompressionalgorithmaswellasitseffectontheaccuracyofstructuralidentificationincludingmodalparametersandsecondorderstructuralparameterssuchasstiffnessanddampingcoefficients.ItisfoundthattheDPCM-basedsensordatacompressionmethodiscapableofreducingtherawsensordatasizetoasignificantextentwhilehavingaminoreffectonthemodalparametersaswellassecondorderstructuralparametersidentifiedfromreconstructedsensordata.