振弦式传感器测频技术的研究-温宗周

JournalofXi’anPolytechnicUniversity26111320122Vol．26N[e-mail]3S6965TP216A．1．．．3．2．．．4．3．．．．1．、．．1LM3S6965、、、．122.1、、、．-．-6．2.2．．4．400～6000Hz32LM3S6965400～6000Hz．．2210ms．10ms．2.3．400～6000Hz10s．2s．Sweepfreq－sweepSweepfq//unsignedintvaluev1v2fq．flag=0//iffq．Freq＞6200fq．Freq=6200//6200value=8000000/fq．Freq//TimerEnableTIMER0－BASETIMER－A//PWMATimerLoadSetTIMER0－BASETIMER－Avalue//PWMA371TimerMatchSetTIMER0－BASETIMER－Avalue/2//PWMAv1=18－fq．Freq/400//60003MS40017MSdelay－msv1TimerDisableTIMER0－BASETIMER－ATimerLoadSetTIMER0－BASETIMER－B50000GPIOPinWriteGPIO－PORTE－BASEGPIO－PIN－1～GPIO－PIN－1GPIOPinWriteGPIO－PORTE－BASEGPIO－PIN－0～GPIO－PIN－0v1=10000/fq．Freqdelay－msv1//12t=12/SGPIOPinWriteGPIO－PORTE－BASEGPIO－PIN－1GPIO－PIN－1GPIOPinWriteGPIO－PORTE－BASEGPIO－PIN－0GPIO－PIN－0v2=TimerValueGetTIMER0－BASETIMER－Bv2=50000－v2ifv2＞8//8fq．flag=1returnfq//2.4．7．TwNxfx=Nx/Tw．fsTxNsfx=fs/Ns．±1NxNs．．．±1．3．．PE04．PE1．ττ1．τNxNs．fsfx=Nx/Nsfs．343、、、．．47268．5．5/．5/10Hz～10kHz．Vin、U/FFout．Fout/、、．U/F．RxUxU/FFxTxRrstU1U/FF1T1U2U/FF2T2．U/FRx=Ux/i=R×T1T2－Tx/TxT2－T1．113U/F、．．1/μV/Hz48030105045300480.153010.485045.50400480.213010.535045.34500480.183010.505045.41600480.133010.495045.57700480.153010.465045.54800480.173010.545045.43900480.193010.575045.391000480.163010.535045.474．300μV～1mV1mV．112℃．10.2%．5．、．．571．1．J．2005610-15．2．J．2007121-28．3．J．2003163-66．4．J．2007254-55．5．J．201029252-57．6．QuinnRife-JaneJ．2008239136-139．7．J．200725213135-137．8．μC/OS-ⅡJ．200630592-95．ResearchonfrequencymeasurementtechnologyofstringvibrationsensorWENZong-zhouXIAZi-bangLIFu-ningSchoolofElectronics＆InformationXi'anPolytechnicUniversityXi'an710048ChinaAbstractBasedontheworkingcharacteristicsofthestringvibrationsensorakindofnewfrequencymeasure-menttechnologyofstringvibrationsensorwithLM3S6965ascontrolcoreisputforward．ByusingLM3S6965in-ternal16timingcountfunctionexcitationsignaloutputandfrequencysignalmeasurementarecompleted．Tem-peraturecompensationoftheresultscanreducetheinfluenceofenvironmenttemperatureonfrequencymeasure-mentofthestringvibrationsensor．Meanwhiletheprecisionmeasurementmethodisusedtoimprovetheoverallsystemmeasurementaccuracy．KeywordsstringvibrationsensorLM3S6965precisionmeasurementtemperaturecompensation、6726