TAP CHi KHOA HOC DHSP TPHCM ^o 8(74) ndm 2015 \ XAY DL^G MOT SO THI NGHIEM SÛ DUNG CAM BIEN SIEU AM VA PHAN MEM LABVIEW DE DAY HOC CHÛ OHVG D O N G HOC VAT LI 10 N G O MINH NHUT'''', MAI H O A N G P H[.]
TAP CHi KHOA HOC DHSP TPHCM ^o 8(74) ndm 2015 \.XAY DL^G MOT SO THI NGHIEM SU^ DUNG CAM BIEN SIEU AM VA PHAN MEM LABVIEW DE DAY HOC CHU^OHVG D O N G HOC - VAT LI 10 N G O MINH NHUT', MAI H O A N G P H L / O N G " TOM TAT Bdi bdo ndy trinh bdy img dung phdn mim Labview, Card USB Arduino vd cdm bie sieu dm viec xdy dung bg thi nghiem co khd ndng dac, thu nhgn vd xu li chinh xdc cdc dgi lugng vdt li vi chuyin dong ca hgc Vai su ca dgng, ghi nhdn lien tuc vd giao dien giao tiip v&i mdy tinh dan gidn bg thi nghiem ndy co the giup gido vien, hgc sinh thuc hien cdc thi nghiem kiim chung vi cdc dang chuyen dgng chuang "Ddng hpc chat difim " - Vdt li 10 a tren lap hgc hay & nhd Tir khda: Card USB Arduino, cam bifin sifiu am, phdn mfim Labview, thi nghiem vat li ABSTRACT Constructing some experiments using ultrasonic sensors with Labview software to tea Kinetics in grade 10 Physics This paper presents an application of the Arduino UNO Card, ultrasonic sensor an Labview software in the construction of a pilot program, which measures Ihe physical quantities of the mechanical motion With its mobility, continuous recording and simpl computer user interface, the pilot program can help teachers and students easily perfor verification experiments in the classroom or at home Keywords: Card USB Arduino UNO, Ultrasonic sensor, Labview, experiment L Gidi thieu Trong day hpc phdn co hpc d THPT, viec nghien ciiu cae qua trinh cd dien bifin nhanh nhu chuyen ddng ciia cac vat ludn gap khd khan rat Idn vifie xac dinh vi tri ciing nhu gia tdc, van ldc cua vat d mdt thdi diem bdt ki nao dd Neu nhu trudc da\' de khao sat chuyfin ddng cua mgt vat, la Ihudng sii dung phuong phap dung cdn rung difin, chup dnh hoat nghifim, hoac thdi gian chuyfin ddng bdng ddng hd hifin sd va cdng quang dien thi hifin mfit sd bd thi nghifim ghep ndi vdi may vi linh cimg vdi cac phan mfim xCr li so lieu thi nghiem da dugc trang bi va da duac nghien ciiu sii dung day va hpc vat li Cu thfi nhu cac thifit bi ghep ndi may tinh \ a cac phan mem tuong iing cua cac hang nhu: Gassy, Phywe (Diic), Pasco, Vernier (IVK), Coach (Ha Lan) Viet Nam, da cd nhifiu dfi tai luan an, khoa luan nghifin ciiu sir dung cac thiet bi thl nghiem ghep ndi may tinh va thi nghiem phdn tich video ho trg vific day hpc nham ndng cao chdt lugng va hieu qua day hpc vat Ii nhu: luan an tifin sT ciia tac gia Nguyfin Xudn Thanh (2003) vdi dfi tai "Xay dyng phdn mfim phdn tieh video va td chiic hoat ddng nhan thiic ciia hpc sinh ;_SV Truang Dgi hpc Sif pham TPHCM; Email minhnhutcom@gmail.com ThS, Tfircrng Dgi hpc Si/ phgm TPHCM 60 TAP CHi KHOA HOC OHSP TPHCM day hpe cac qua trinh co hgc bifin ddi nhanh theo quan diem li luan day hpc hifin dai" [7]; Iuan van thae sT cua tac gid Le Hoang Anh Linh (2013) vdi dfi tai "Thiel ke bd thi nghifim co hgc diing cdm bifin Sonar va sir dung day hpc chuang cac dinh ludt bdo loan - ldp 10 THPT' [3] Nhd vao cac thi nghifim kfit ndi may linh, phan mfim phdn tich video ma viec dac va xir li sd Hfiu thi nghiem trd nen nhanh chdng va dfi dang hon giiip cho vific day va hpc vat li cua giao vifin va hpc sinh dat hifiu qua tdl hon Tuy nhifin, d Viet Nam cac nghifin Cliu vific thiet kfi, xay dung cac bd thi nghifim vdt li ket ndi may tinh van cdn han che hoac chi dimg d miic nghifin Cliu sir dyng chua dap iing cho vific trang bi va diing day hgc vat li d trudng THPT Mae khae eac bd thi nghiem ghep ndi may tinh nfiu nhdp ttr nudc ngoai thi gid rat cao khdng phii hgp vol tifiu chi xay dung phdng thi nghiem vdt li d trudng THPT Vi vay, cdn thifit phai chfi lao cae cam bifin don gidn, gia thap phil hgp vdi ddi tugng Xuat phat ttr nhung khd khan dd, chiing tdi da thifit kfi va xdy dung mgt bp thi nghifim ed khd nang dac cac dai Iugng chuyfin dpng CO nhu tga do, van ldc, gia tdc cua mgt vdt chuyen ddng mdt each nhanh chdng vdi dp chinh xac cao bang cam bifin sifiu am va lap trinh ket ndi bang phdn mem Labview Tinh mdi ciia bai bao la xay dyng dugc bg thi nghifim ddp ling nhu cdu d?y hgc vat Ii chuong dgng hgc vdi gia re, ddng thdi ihifit kfi dugc chuong trinh trfin may linh vdi giao dipn bdng tifing Viet Ngoai ra, Ngo Minh Nhut vd tgk chuang trinh cdn cung cap mdt sd bai thi nghiem mau, giao vifin hay hgc sinh cd the dya vao dd dfi thifit kfi them cac bai thi nghifim khac Npi dung Sau mgt thdi gian nghien ciiu va thifit kfi, chiing tdi da xay dyng dugc bd thi nghifim gdm: Hinh 2.1 Hop chim cdm bien sieu dm vd bo mgch Arduino • Mdt bd thi nghifim (hinh 2.1) gdm: Cam bifin sieu am Board Arduino Day kfit ndi vdi may tinh ca nhan thdng qua cdng USB • Giao difin ngudi dung tren mdy tinh canhdn (hinh 2.2) —::;•£ ^H'i.fr Hinh 2.2 Giao dien chuong trinh tren mdy tinh cd nhdn 2.L Card USB Arduino UNO Arduino UNO la mdt board mach vi xir Ii cd kha nang kfit ndi, thu nhdn va 61 S3 8(74) nam TAP CHi KHOA HOC DHSP TPHCM xuAi tin hifiu difiu khifin dfin cac thifit bi phdn Cling nhu cac cam bifin ddng co hoac mdt sd thiel bi ngoai \i khdc cung nhu xii li tin hifiu tra \e tir cam bifin va cho la ket qua sd lieu can So cac chdn ciia cam bien SRF04 l.GND Echo Trig Vcc Dfi khodng each tdi vat can bg phat (Trigg) cua cam bifin se xudt mdt xung dai 10 ys tan sd 40 kHz Sdng am tru\ en tdi \ at can \ a bi phan xa lai bd thu lin hifiu Neu ggi t la khoang thai gian tir liic phat dfin thu dugc tin hieu thi khoang each tdi vat can tinh theo cdna thlic d - Minh 2.3 Board mach Arduino Uno Trong bd thi nghifim na\ mach Arduino nhu mdt mach difiu khifin trung gian gitra may tinh va cam bifin sifiu am Mach Arduino UNO sc nhan lfinh tir ngudi dimg thdng qua giao difin tren ma\' tinh sau thyc hifin cac lfinh xong mach Arduino UNO se trd lai tin hifiu thu nhdn dugc lir cam bifin sifiu dm Nhd vao chucmg trinh ma\ linh ma lin hifiu dd se dugc tin loan \ a cho kfit qua cudi cCmg la khoang each ldi vat can khao sal 2.2 Cdm bien sieu dm De xdc dinh tpa dp cua vat can khao sal d nhtmg thdi difim khac chiing tdi sir dung cam bien sifiu am SRF04 Da\ la Ioai cam bifin khodng each theo phuong phap thdi gian tru\'fin cd cdu tao gdm mdt ddu phat va mdt ddu thu tin hifiu nhu hinh 2.4 1234 Hinh 2.4 Cdm biin sieu dm SRF04 2015^ Vdi V la \ an toe sdng am khdng Do each thlic hoat ddng ciia cam bien sifiu am hoat ddng dya trfin phuang ph^ thdi gian uuyfin nen cd nhifiu nguyfin nhdn ddn dfin sai sd cua phep Iam cho sd lieu thu dugc thifiu chinh xac hoac bi nhifiu Mdt sd ngmfin nhdn chinh sau: Su thay ddi ciia tdc truyfin sdng dm khdng Sy luong lae ciia sdng tdi vdi bfi mat ciia ddi tugng cdn Tdm quel ciia cdm bien sifiu am co gdc md ldn (khoang 53 dp) Tir da\ chung tdi dua mdt so bifin phap khac phuc qua trinh thiet kc nhu sau: Khdc phuc su thay doi ciia tdc truyen song dm khong khi: Nhu ta da bifil van tdc truyfin sdng am khdng phu thudc vao nhifit dp moi trudng nhifii dp mdi trudng thay doi thi van tdc truyfin sdng thay ddi ddn den kfit qud khoang each se khac thyc hien d nhiing ncri cd nhifit moi trudng khac Vi va> chung tdi sir dung them cam bifin nhiet LM35DZ dfi nhifit dp mdi Irudng tai noi tien hanh thi nghifim Cdng thiic gdn diing TAP CHi KHOA HOC DHSP TPHCM bifiu difin su phu thudc ciia van tdc truyen sdng va nhifit do: v ==; 0.6? + 33I(m/.?) (0.6/-F33l).Ar suy a = -^^ Vdi t la nhifit dp mdi trudng (0"C); AT la thdi gian truyen sdng (s) Khdc phuc su tuang tdc ciia song v&i be mat ciia doi tuang cdn do: Khi sdng dm tac ddng vdi bfi mat ciia ddi tugng can do, tin hieu bj phan xa theo nhifiu hudng khac nfiu nhu gdc tdi cua chiim sdng khdng vudng gdc vdi bfi mat phan xa hoac be mat phan xa khdng bang phang Difiu lam cho ddu thu tin hifiu khdng nhdn dugc tin hifiu phan hdi hodc tin hifin phdn hdi bj phan xa theo nhifiu hudng khac nhau, each khac phuc lifin hanh khao sat thi nghifim cam bien sieu dm phai dat vudng gdc vdi ddi lugng can khao sat, trfin ddi tugng can khao sat can gan them tam phang ddi difin cam bifin dfi ddm bao sdng tdi phan xa tdt Khdc phuc goc ma cua cdm bien: Do gdc md cua cam bifin ldn, nen mgt vat nam gdc md d mdt khoang each ndo cam bifin vdn cd thfi dgc dugc cac tin hifiu, dan dfin hifin tugng nhifiu Vi vay, khoang cdch, chiing tdi ldy gia tri trung binh ciia nhifiu Ian ddng thdi thi nghifim khao sat, vat cdn di chuyfin pham vi tir 10 em dfin n o cm Sau da thyc hifin cdc bifin phdp gidm sai sd cua cam bien, chiing tdi thu duge bdng sd Hfiu sai sd eiia cam bifin theo khodng each nhu bang 1: Ngo Minh Nhui vd tgk Bdng Sai s(') cua cdm bien sieu dm u* v-ip? H 10 15 20 25 30 40 50 60 1.61 2.53 2.26 0.37 1.37 1.52 2.6 70 80 90 100 110 120 150 • 2.42 1.84 3.2 1.52 3.01 5.04 8.13 2.22 Sau da xac dinh dugc tga ciia vat can khao sat d nhtmg thdi diem khac nhau, chiing ldi sir dyng thudt toan tinh dao ham dfi tinh van tdc va gia tdc tire thdi cua \ at d nhimg thdi difim khac 2.3 Giao dien tren mdy tinh cd nhdn Dya trfin ngdn ngir lap trinh dd hga Labview chiing tdi da ihici kfi va xdy dyng mdt giao difin ngudi diing don gidn va true quan Giao difin chuang trinh la noi hien thj sd lieu thi nghifim dudi dang cac dd thi, bang bifiu cung nhu cho phep ngudi diing cd thfi thao tac vific thu thap xir Ii sd lieu, luu kfit qua hoac md tap tin Clia cac bai thi nghiem da lam trudc Cira sd giao difin chuong trinh nhu hinh 2.2 Ket qua thi nghifim dugc thfi hifin thdng qua cac dd thj va bdng sd lieu Thdng qua dd thi ta cd thfi nhdn biet dugc cdc dang chuyfin ddng cua vat can khao sat, ddng thdi ngudi diing ed thfi tinh gia tri trung binh, khdp ham, tinh tich phdn, lim gid tri ldn nhdt, nhd nhdt nhd vao cdng cy xu Ii sd Hfiu Kfit qua thi nghifim cd thfi dugc luu lai dudi dang tap tin cd phan md rgng la txi va md lai tap tin dd can sir dyng Ngoai 63 TAP CHi KHOA HOC DHSP TPHCM giao difin cdn cd phan "Hudng dan su dung chuong trinh" giup ngudi dung cd the de dang sir dyng eac chirc nang cua chuong trinh vific thu thap va xir li sd Hfiu thi nghiem Mot so bai thi nghiem da xay dung 3.1 TIti nghiem khdo sdt chuyen dgng thang bien ddi diu Chuyfin dpng thang bifin ddi dfiu la chuyen ddng thang dp ldn cua van ldc tire thdi tang hoac gidm dfiu theo thdi gian Phuong trinh tpa dp ciia chuyfin ddng thang bifin ddi dfiu: x = x^^v^t + -at' (3.1) Trong dd Xy VQ la vj tri va van tdc liic dau cua chuyfin dgng Phuang trinh van tdc tiic thdi cua v$t theo thdi gian: v = v^ + at (3.2) Nfiu vat chuyfin dgng nhanh ddn dfiu thi a.v > Nfiu vat chuyfin ddng chdm ddn dfiu thi a.v < 3.L1 Bo tri thi nghiem khdo sdt chuyin dong thdng nhanh ddn diu Bo tri thi nghiem nhu hinh 3.1 Hinh 3.1 Bo tri thi nghiem khdo sdt chuyen dgng thdng nhanh ddn diu 64 So 8(74) nam 2015 Xe khdi lugng m = 0.5 kg dugc ddt trfin ray Thanh ray dugc dat nghieng mgt gdc 20** so vdi mat ban, cam bifin dat phia sau xe (hinh 3.1) Trong thi nghiem khdo sat ma sat ciia xe vol tharih ray la khdng dang ke Kfit ndi cam bifin sifiu am vdi cdng USB ciia mdy tinh va khdi ddng chuang trinh giao dien ngudi diing trfin may linh Tifin hanh thi nghiem, tha xe khdng van tdc ddu tir dinh ray, xe se chuyfin ddng nhanh ddn xudng chan ray Kfit qua thi nghiem dugc thl hifin tren chuong trinh giao difin may tinh, dya trfin bdng sd lieu thu thap dugc, chiing la se tifin hdnh phan lich dd thi ve dugc va linh dugc cae gia tri van tdc, gia tdc ciia xe chuyen ddng Kfit qua thi nghifim dugc thfi hifin trfin dd thi nhu hinh 3.2 Hinh 3.2 Dd thi tga - thai gian (a), van tdc - thai gian (b) Ngd Minh Nhut vd tgk TAP CHi KHOA HOC OHSP TPHCM Ta thdy phan dugc td den d dd thi the hifin sy thay ddi vi tri ciia vdt cd dang parabol, va thi van tdc - thdi gian cd dang dudng thang cd he sd gdc duong phu hgp vdi cdng thire (3.2) Sii dung chlie nang khdp ham dfi so sanh ham sd thyc nghifim vdi ham sd li thuyfit, tir dd tim duge phuong trinh tga ciia chuyfin dgng va phuong trinh van tdc cua vdt theo thdi gian Phuang trinh tpa dp cua chuyfin ddng: ;c = 0,112 + 0,134/+ 1,66/" (3.3) Phuong trinh van tdc theo thdi gian: v = 0,110+3.35/ (3.4) Tren hinh 3.3 la dd thi bifiu dien sir thay ddi gia tdc theo thdi gian Gia tri gia too a thu dugc vung dugc td den cd gia tri thay ddi, vay.dd thi cd dang gan diing vdi dd Ihi li thuyet (Do chiing tdi chua tim dugc cam bien sifiu dm cd chat lugng, ddng thdi, lap trinh tinh dao ham dya tren sd lieu toa do, tir dd ddn dfin sai sd each tinh gia toe) Tir dd thj, tinh dugc gia tdc trung binh vung dugc td den a = 3,38 m/s^ Mac khac, bang phuong phap ddng lyc hgc, ta chiing minh dugc gia tdc cua xe chuyen ddng tren ray dat nghifing gde a dugc linh theo cdng thlic: a=gsina (3.5) Tifin hanh thi nghiem khao sat bang each thay ddi gdc nghifing cua ray so vdi mdt ban gia tdc mang iing vdi mdi gdc a va so sdnh vdi gia tri tinh theo cdng thiic (3.5) Bdng Ket qud gia tdc Ihay doi goc nghieng a 30 25 20 15 10 4.80 4.13 3.23 2.49 1.65 0.89 4.90 4.14 3.35 2.54 1.70 0.85 2.04 0.24 3.58 1.97 2.94 4.71 Nhan xet: Gia tri gia tdc dugc gan diing vdi gia tri gia tdc tinh theo H thuyfit (duge chimg minh bang phuang phap ddng lyc hgc) Sai sd ciia phep nhd hon 5% chiing td bd thi nghiem hoat ddng tuong ddi chinh xac Ngoai each bd tri thi nghifim nhu trfin, ta cd thfi bd tri thi nghiem theo phuang an nhu hinh 3.4 Vdt chuyfin ddng la mdt chiec xe (1) khdi lugng M0.5 kg dugc dat trfin ray (2) nam ngang Mdt vat cd khdi lugng m = lOOg ndi vdi xe bang mdt sgi ddy thdng rdng rpc cd khdi lugng khdng dang ke Cam bifin (3) dat phia sau xe Hinh 3.3 Dd thi gia tdc - th&i gian cua chuyen dgng nhanh ddn deu 65 TAP CHi KHOA HOC DHSP TPHCM S6 8(74) nam 2015 Hinh 3.6 Bd tri thl nghiem khdo sat Hinh 3.4 Bo tri thi nghiem chuyen chuyen dong chgm ddn deu dqng thang nhanh ddn deu theo phuxmg dn khdc Ket qud thi nghiem duoc trinh bdy Thanh ray dtrgc dat nghieng mpt hinh 3.5 goc 8° so voi mat ban Trong thi nghiem khao sat nay, ma sat cua xe voi ray la khong dang kk KSt n6i cam bien sieu am voi cong USB cua may tinh va khoi dong chuong trinh giao dien nguoi diing Hinh 3.5 Bo thi tpa - thai gian thtrc hien phuang dn Phucmg trinh toa dp cua chuyen dpng ling vol viing thj dupc to den: ir = 0,07+0.118/ + 0,707/- (3.6) Til (3.6) suy a = l,14lm/s^ Kat qua gSn bang vdi gia tri tinh theo li thuyet: a„=J!^=^^^.^.aml,^ m+M 0,1+0.5 (cong thirc dupc chirng minh theo phircmg phap dpng luc hpc) 3.1.2 Bo tri thi nghiem khao sdt chuyin ddng thang chdm ddn diu B6 tri thi nghiem nhu hinh 3.6 Tien hanh thi nghiem: cung cap cho xe mot van toe ban dau v„, xe se chuyen dpng cham dto dSu d6n mpt vi tri ma vto toe ciia xe bang khong, xe se dimg lai va chuyen dpng nhanh dta deu ngupc tro lai Kft qua thi nghiem dupc ihi hien tren chuong trinh giao dien tren may tinh, dua tren btog s6 lieu thu thap ducrc, chiing ta se tien hanh phto tich d6 thi ve dupc va tinh dupc cac gia tri van t6c, gia tpc cua xe chuyen dpng K6t qua thi nghiem duoc XVA hien hinh 3.7 TAP CHi KHOA HOC DHSP TPHCM ven dgng thiing dfiu: x-x^-^vt (3.7) Bd tri thi nghifim nhu hinh 3.8 Hinh H Bo iri thi nghiem khdo sdt chuyen dgng thang deu Hinh 3.9 Do thi toa do, van tdc theo th&i gian chuyen dgng thdng deu Dd thi tga - thdi gian la mdt dudng thang phii hgp vdi cdng thiic (3.7) K.hdp ham, chiing ta tim dugc phuang trinh tpa cua chuyfin dpng img vdi \'iing dugc td den trfin dd thi: A-= 0.079 + 0.565/ Gia tri van tdc trung binh khdp dugc tir thi tpa - thdi gian la 0,565 m/s, gan diing vdi gid trj van ldc trung binh tinh tir dd thi van tdc - thdi gian la 0.546 m/s Nhu vdy vat chuyen thang dfiu vdi van tdc gan bang 0,55 m/s TAP CHi KHOA HOC DHSP TPHCM 3.3 Bd tri thi nghiem khdo sdt su rai tudo Rai ty la mdt trudng hgp dac bifit ciia chuyen ddng thang nhanh dan deu vdi gia toe a = g = 9,8 m/s' Nhu vay dd thi tga dp - thdi gian vd thi van tdc - thdi gian cd dang gidng nhu thi nghifim thdng nhanh ddn dfiu Bd tri thi nghifim nhu hinh 3.10 Hinh 3.10 Bo tri thi nghiem khdo sdt su rai tu Trong thi nghiem roi tu do, la phai chgn vdt nang cd kich thudc nhd dfi giam lyc can cua khdng tac dung vao vdt Khi trpng lugng ctia vat Idn, la cd thfi bd qua luc cdn eiia khdng va xem nhu vat roi ly Tu\ nhifin nfiu chgn vdt ed kich thudc nhd thi sdng am cdm bifin phat se khdng thfi phdn xa Iai ddu thu, va\ cam bien sfi khdng da dugc khodng each tdi vat can khao sdt Trong thi nghifim khao sdt na\ vdl ndng dugc ehgn de khao sat thi nghifim roi la qua bdng rd Nfiu khdng can chinh xac cao, ta vdn cd thfi coi su rcri ciia qua bdng gdn dung la sy roi ty /" I Hinh 3.11 Do thi tga - th&i gian ciia qud bong rai tu So 8(74) ndm 201 3.4 Thi nghiem khdo sdt dao ddn^ dieu hba cua ldc Ib xo Bd ui thi nghifim dao dgng ciia cor ldc Id xo gdm: mdt Id xo cd ciing k, moi ddu dugc mdc vdo gia dd ddu cdn lai tree qua nang m = 50g Keo qud nang khoi \\ tri can bang va tha cho dao dgng va khao sat dao ddng ciia lac Id xo Ket qua thi nghiem dugc trinh bay d hinh 3.12 Hinh 3.12 Do thi toa - th&i gian ciia ldc Id xo Ket Iuan va hirdng phat trien ciia de tai 4.L Ket ludn Tir vific nghifin ciiu cdc kien thiic CO ban ve ngdn ngtr lap trinh Labview viec kfil ndi vdi cac thifit bi ngoai vi chting tdi da thifit kfi vd xay dung dugc mgt sd thi nghifim chuong "Dpng hgc chat difim - Vdt Ii 10" bdng cdm bi£n sifiu dm va Card USB Arduino Bd thi nghifim da giai quyfit dugc mdt so ban chfi cua cdc bd thi nghifim truyen thdng vific dat vd xii Ii kfit qiia thi nghifim, giiip cho gido vifin va hoc sinh de dang thyc hifin cac thi nghiem kifim chimg trfin Idp hay d nha Ngoai ra, vdi gia thdp hon r§l nhifiu so vdi cdc bd thi nghifim n h ^ tir nudc ngoai nfin cd thfi trang bi rgng rai cde hirdng THPT (Chi phi cho mpt bg thi nghiem vdo khoang 750.000d) TAP CHl KHOA HOC DHSP TPHCM 4.2 Hu&ng phdt trien cUa de tdi Bd thi nghiem thu nhdn ket qua tuong ddi tdt d cac dang chuyfin ddng thang deu, thang nhanh ddn dfiu, eham ddn deu, dao ddng ciia eon lac Id xo Tuy nhifin vdn cdn mdt sd khuyet diem cdn cai lien nhu thdi gian kfit ndi gitra may linh ca nhdn vdi Card USB Arduino cdn chdm gay khd khan cho ngudi sir dung; sai sd cua cam bifin edn ldn (khi vat dat xa hon 1,5m thi sai sd ldn hon 5%); de bi loi kfit ndi giira may tinh vdi Card Arduino; sai Ngo Minh Nhut vd tgk sd tinh eac gia tri dao hdm cua cac dai lugng vat H, dac bifit la tinh va ve thi gia tdc d hinh 3.3 Vi vdy, de khac phuc nhung khuyfit difim trfin, thdi gian sap tdi, chiing tdi se tim vd thay the cam bien sifiu dm cd chinh xac cao hon de giam sai sd eiia kfit qua thi nghiem Ngoai ra, chung tdi se tiep tuc rad rpng bg thi nghifim cho viec thiet ke cdc thi nghiem chuong ddng lyc hgc va cac dinh luat bao loan sir dyng them cdm bifin gia tdc va cam bifin Iyc TAI LIEU THAM KHAO Nguyfin Ba Hai (2011^ Lap trinh LabView Trinh ca bdn, Nxb Dai Qufic gia TP Hd Chi Minh Dinh Sy Hifin, Lfi Htm Phuc, Luong Qudc Dung (2004), "Nghifin cim chfi tao KIT cam bifin ghep vdi NI DAQ PCI 6024E'', Hdi nghi &ng dung vdt li todn qudc ldn thd2, TP Hd Chi Minh, thang 12/2004 Lfi Hoang Anh Linh (2013), Thiet ke bg thi nghiem co hgc diing cdm bien Sonar vd sir dung dgy hgc chuang cdc dinh ludt bdo lodn - l&p 10 THPT, Ludn van Thac sT Giao due, Trudng Dai hpc Su pham TP Hd Chi Minh Nguyfin Xuan Thanh (2003), Xdy dung phdn mem phdn tich video vd to chuc hoat dgng nhdn thuc cua hgc sinh dgy hgc cdc qud trinh co hgc bien doi nhanh theo quan diem li ludn dgy hgc hien dgi, Luan an Tifin si Giao due, Tnrdng Dai hgc Su pham Ha Ngi Jeffery Travis, Jim Kring (2006), Labview for everyone Prentice Hall Malan Shiralker (2007), Labview Graphical Programming Course, Rice University, Houston, Texas http://www ni com (Ngdy Tda soan nh$n duvc biii: 18-4-2015; ng^yphAn bi§n ddnh gid: 12-5-2015; ngdy ChSp nhdn ddng: 24-8-2015) 69 ... Minh Nhui vd tgk Bdng Sai s('') cua cdm bien sieu dm u* v-ip? H 10 15 20 25 30 40 50 60 1.61 2.53 2.26 0.37 1.37 1.52 2.6 70 80 90 100 110 120 150 • 2.42 1.84 3.2 1.52 3.01 5.04 8.13 2.22 Sau da xac... thdi gian cd dang gidng nhu thi nghifim thdng nhanh ddn dfiu Bd tri thi nghifim nhu hinh 3 .10 Hinh 3 .10 Bo tri thi nghiem khdo sdt su rai tu Trong thi nghiem roi tu do, la phai chgn vdt nang cd... ve ngdn ngtr lap trinh Labview viec kfil ndi vdi cac thifit bi ngoai vi chting tdi da thifit kfi vd xay dung dugc mgt sd thi nghifim chuong "Dpng hgc chat difim - Vdt Ii 10" bdng cdm bi£n sifiu