zvinodzidziswa Dhizaina Inoshanda ECG Ine Automated Plotting yeBiosignal
Dhizaina Inoshanda ECG Iine Otomatiki Roti yeBiosignal
Iyi purojekiti inosanganisa zvese zvakadzidzwa semester ino uye inoishandisa kune rimwe chete basa. Basa redu nderekugadzira dunhu rinokwanisa kushandiswa se electrocardiogram (ECG) nekushandisa chiridzwa. amplifier, lowpass sefa, uye notch filter. ECG inoshandisa ma electrode akaiswa pamunhu kuyera uye kuratidza kushanda kwemoyo. Maverengero akaitwa zvichibva paavhareji yemwoyo yevakuru, uye ekutanga edunhu masisitimu akagadzirwa paLTSpice kuti aone kuwana uye cutoff frequency. Zvinangwa zvechirongwa chekugadzira ichi ndezvizvi:
- Shandisa hunyanzvi hwezviridzwa hwakadzidzwa mulabhu semesita ino
- Dhizaina, gadzira, uye simbisa mashandiro echinhu chekutora chiratidzo
- Simbisa mudziyo pachinhu chemunhu
Supplies:
- LTSpice simulator (kana yakafanana software) Breadboard
- Various resistors
- Various capacitors
- Opamps
- Electrode waya
- Kuisa voltage source
- Mudziyo wekuyera kubuda kwevoltage (kureva oscilloscope)
Danho 1: Ita Masvomhu eChikamu Chese chedunhu
Mifananidzo iri pamusoro inoratidza maverengero edunhu rega rega. Pazasi, inotsanangura zvakawanda nezve zvikamu uye maverengero akaitwa.
Instrumentation Amplifier
An instrumentation amplifier, kana IA, inobatsira kupa huwandu hukuru hwekuwana kune yakaderera-level masaini. Inobatsira kuwedzera saizi yechiratidzo kuti inyatso kuoneka uye waveform inogona kuongororwa.
Pamaverengero, takasarudza maviri asina kujairika resistor values eR1 neR2, ari 5 kΩ uye 10 kΩ, zvichiteerana. Isu tinodawo kuti hupfumi huve 1000 kuitira kuti chiratidzo chive nyore kuongorora. Reshiyo yeR3 neR4 inozogadziriswa neinotevera equation:
Vout / (Vin1 – Vin2) = [1 + (2*R2/R1)] * (R4/R3) –> R4/R3 = 1000 / [1 + 2*(10) / (5)] –> R4/ R3 = 200
Isu takazoshandisa chiyero ichocho kusarudza kuti imwe neimwe resistor kukosha ichavei. Izvo zvakakosha ndezvizvi:
R3 = 1 kΩ
Notch Sefa
Iyo notch sefa inodzikisira masaini mukati meiyo nhete bhendi yemafrequency kana kubvisa kamwe chete frequency. Frequency yatinoda kubvisa pakadai i60 Hz nekuti ruzha rwakawanda rwunogadzirwa nemagetsi ndere frequency iyoyo. AQ factor ndiyo chiyero chepakati frequency kune bandwidth, uye inobatsirawo kutsanangura chimiro chehukuru chirongwa. A hombe Q factor inokonzeresa kuita nhete yekumira bhendi. Pakuverenga, tinenge tichishandisa kukosha kweQ kwe8.
Takasarudza kusarudza capacitor tsika dzataive nadzo. Saka, C1 = C2 = 0.1 uF, uye C2 = 0.2 uF.
Maequation atichange tichishandisa kuverenga R1, R2, neR3 ndeaya anotevera:
R1 = 1 / (4*pi*Q*f*C1) = 1 / (4*pi*8*60*0.1E-6) = 1.6 kΩ
R2 = (2*Q) / (2*pi*f*C1) = (2*8) / (2*pi*60*0.1E-6) = 424 kΩ
R3 = (R1*R2) / (R1 + R2) = (1.6*424) / (1.6 + 424) = 1.6 kΩ
Lowpass Sefa
Iyo yakaderera pass sefa inodzikisira ma frequency epamusoro uku ichibvumira yakaderera ma frequency kupfuura. Iyo cutoff frequency ichave yakakosha ye150 Hz nekuti ndiyo chaiyo ECG kukosha kune vakuru. Zvakare, kuwana (K kukosha) kuchave 1, uye maconstants a uye b ari 1.414214 uye 1, zvichiteerana.
Isu takasarudza C1 kuenzana ne68 nF nekuti isu taive neiyo capacitor. Ku nd C2 takashandisa inotevera equation:
C2 >= (C2*4*b) / [a^2 + 4*b(K-1)] = (68E-9*4*1) / [1.414214^2 + 4*1(1-1)] –> C2 >= 1.36E-7
Naizvozvo, isu takasarudza C2 kuenzana ne0.15 uF
Kuverenga iwo maviri resistor values, taifanira kushandisa anotevera equations:
R1 = 2 / (2*pi*f*[a*C2 + sqrt([a^2 + 4*b(K-1)]*C2^2 – 4*b*C1*C2)] = 7.7 kΩ
R2 = 1 / (b*C1*C2*R1*(2*pi*f)^2) = 14.4 kΩ
Danho 2: Gadzira Schematics paLTSpice
Zvese zvitatu zvikamu zvakagadzirwa uye zvaiitwa mumwe nemumwe paLTSpice ine AC yekutsvaira ongororo. Hunhu hunoshandiswa ndihwo hwatakaverenga mudanho rekutanga.
Danho 3: Gadzira Instrumentation Ampchakaipa
Isu takagadzira chiridzwa amplifier pabhodhi rekudya nekutevera schematic paLTSpice. Payakangovakwa, iyo yekupinza (yero) uye yakabuda (girinhi) voltages akaratidzwa. Mutsara wakasvibira unongowana kuwana kwe743.5X uchienzaniswa neyero mutsara.
Danho 4: Vaka iyo Notch Sefa
Tevere, isu takavaka notch sefa pabhodhi rekudya zvichibva pane schematic yakagadzirwa paLTSpice. Yakavakwa padivi pedunhu reIA. Takazorekodha input and output voltage inokoshesa pamafrequency akasiyana siyana kuona ukuru. Zvadaro, takaita graphed magnitude vs. frequency pachirongwa kuti tienzanise neLTSpice simulation. Chinhu chega chatakachinja chaive kukosha kweC3 neR2 ari 0.22 uF uye 430 kΩ, zvichiteerana. Zvakare, iyo frequency yairi kubvisa ndeye 60 Hz.
Danho 5: Vaka iyo Lowpass Sefa
Isu takazovaka iyo yakaderera pass sefa pabhodhi rechingwa zvichibva pane schematic paLTSpice padivi penotch sefa. Takazorekodha vhoriyamu yekupinda nekubudatages pama frequency akasiyana ekuona ukuru. Zvadaro, takaronga hukuru uye frequency kuti tiienzanise neLTSpice simulation. Kukosha chete kwatakachinja kune iyi sefa yaive C2 inova 0.15 uF. Iyo cutoff frequency yatanga tichiona ndeye 150 Hz.
Danho 6: Muedzo Panyaya Yemunhu
Kutanga, batanidza zvitatu zvega zvega zvedunhu pamwechete. Zvadaro, zviedze nekateedzerwa kurova kwemoyo kuti uone kuti zvese zviri kushanda. Zvadaro, isa maelectrodes pamunhu kuitira kuti chakanaka chiri paruoko rwerudyi, negative chiri pagumbo rekuruboshwe, uye ivhu riri pachitsiko chekurudyi. Kana munhu wacho achinge agadzirira, batanidza bhatiri re9V kuti usimbise opamps uye kuratidza chiratidzo chekubuda. Ziva kuti munhu wacho anofanira kuramba akanyarara kweanenge masekonzi gumi kuti awane kuverenga chaiko.
Makorokoto, iwe wakabudirira kugadzira otomatiki ECG!
Zvinyorwa / Zvishandiso
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zvinodzidziswa Dhizaina Inoshanda ECG Ine Automated Plotting yeBiosignal [pdf] Mirayiridzo Dhizaina Inoshanda ECG Iine Otomatiki Roti yeBiosignal, Dhizaina Inoshanda ECG, Inoshanda ECG, Kurongeka kweBiosignal. |
