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Ama-Actuator asetshenziswa yonke indawo futhi adala ukunyakaza okulawulwayo ngokusebenzisa amandla ashukumisayo alungile noma i-torque ukwenza imisebenzi ehlukahlukene ekukhiqizeni nasekusebenzeni okuzenzakalelayo kwezimboni.Isidingo samadrayivu asheshayo, amancane nasebenza kahle kakhudlwana sishayela ukuqamba okusha ekwakhiweni kwedrayivu.Amadrayivu e-Shape Memory Alloy (SMA) anikezela ngenani lezinzuzo ngaphezu kwamadrayivu avamile, okuhlanganisa isilinganiso esiphezulu samandla nesisindo.Kule dissertation, kwasungulwa i-actuator enezimpaphe ezimbili ezisekelwe ku-SMA ehlanganisa izinzuzo zemisipha enophaphe yezinhlelo zebhayoloji kanye nezakhiwo ezihlukile zama-SMA.Lolu cwaningo luhlola futhi lunwebe ama-activator e-SMA angaphambilini ngokwakha imodeli yezibalo ye-actuator entsha esekelwe ekuhlelweni kwentambo ye-SMA ene-bimodal kanye nokuyihlola ngokuhlola.Uma kuqhathaniswa namadrayivu aziwayo asekelwe ku-SMA, amandla okuqalisa edrayivu entsha okungenani aphakeme ngokuphindwe ka-5 (kufika ku-150 N).Ukuncipha kwesisindo okuhambisanayo kumayelana nama-67%.Imiphumela yokuhlaziywa kokuzwela kwamamodeli ezibalo iwusizo ekulungiseni amapharamitha wedizayini nokuqonda amapharamitha abalulekile.Lolu cwaningo luqhubeka luveza idrayivu yesiteji se-Nth enamazinga amaningi engasetshenziswa ukuze kuthuthukiswe ukuguquguquka.Ama-actuator emisipha e-dipvalerate asuselwa ku-SMA anohlu olubanzi lwezinhlelo zokusebenza, kusukela kokuzenzakalelayo kuye kumasistimu okulethwa kwezidakamizwa anembayo.
Izinhlelo zebhayoloji, njengezakhiwo ezinemisipha yezilwane ezincelisayo, zingasebenzisa ama-actuator amaningi acashile1.Izilwane ezincelisayo zinezinhlaka ezihlukene zemisipha, ngasinye sifeza injongo ethile.Kodwa-ke, ingxenye enkulu yesakhiwo sezicubu zomzimba ezincelisayo zingahlukaniswa zibe izigaba ezimbili ezibanzi.Parallel futhi pennate.Kuma-hamstrings nakwamanye ama-flexible, njengoba igama libonisa, imisipha ehambisanayo inemicu yemisipha ehambisana ne-tendon ephakathi.Iketango lemicu yemisipha likleliswe futhi lixhunywe ngokusebenza yizicubu ezixhumeneyo eziwazungezile.Nakuba le misipha kuthiwa ine-excursion enkulu (ukunciphisa amaphesenti), amandla abo emisipha jikelele alinganiselwe kakhulu.Ngokuphambene nalokho, ku-triceps ithole muscle2 (i-lateral gastrocnemius (GL) 3, i-medial gastrocnemius (GM)4 ne-soleus (SOL)) kanye ne-extensor femoris (quadriceps) izicubu ze-5,6 ze-pennate muscle zitholakala ku-muscle7 ngayinye.Esakhiweni se-pinnate, izintambo ze-muscle ku-musculature bipennate zikhona ezinhlangothini zombili ze-tendon ephakathi kuma-oblique angles (ama-pinnate angles).I-Pennate ivela egameni lesiLatini elithi "penna", okusho ukuthi "ipeni", futhi, njengoba kuboniswe kumfanekiso.1 inokubukeka okufana nosiba.Imicu yemisipha ye-pennate mifushane futhi i-angle ku-axis longitudinal yomsipha.Ngenxa yesakhiwo se-pinnate, ukuhamba okuphelele kwale misipha kuyancishiswa, okuholela ezingxenyeni eziguquguqukayo kanye ne-longitudinal yenqubo yokunciphisa.Ngakolunye uhlangothi, ukusebenza kwale misipha kuholela ekuqineni kwemisipha jikelele ngenxa yendlela indawo ye-physiological cross-sectional ikalwa ngayo.Ngakho-ke, endaweni enikeziwe ye-cross-sectional, imisipha ye-pennate izoba namandla futhi izokhiqiza amandla aphezulu kunemisipha enemicu ehambisanayo.Amandla akhiqizwa imicu ngayinye akhiqiza amandla emisipha ezingeni elikhulu kuleyo zicubu zomzimba.Ngaphezu kwalokho, inezici eziyingqayizivele ezifana nokuncipha okusheshayo, ukuvikelwa emonakalweni we-tensile, i-cushioning.Iguqula ubudlelwano phakathi kokufakwayo kwefayibha kanye nokuphuma kwamandla emisipha ngokusebenzisa izici eziyingqayizivele kanye yinkimbinkimbi yejometri yokuhlelwa kwefayibha ehambisana nemigqa yesenzo yemisipha.
Kuboniswa imidwebo eyisikimu yemiklamo ekhona ye-actuator esuselwe ku-SMA ngokuhlobene ne-bimodal muscular architecture, isibonelo (a), emele ukusebenzisana kwamandla okuthinta lapho idivayisi emise okwesandla ecushwa izintambo ze-SMA ifakwe irobhothi leselula elizimele elinamasondo amabili9,10., (b) I-Robotic orbital prosthesis ene-SMA efakwe ngendlela ephikisanayo yokufakelwa kwe-spring orbital prosthesis.Indawo yeso lokufakelwa ilawulwa isignali evela kumsipha we-ocular we-eye11, (c) Ama-actuator e-SMA alungele ukusetshenziswa ngaphansi kwamanzi ngenxa yokusabela kwawo kwemvamisa ephezulu kanye nomkhawulokudonsa ophansi.Kulokhu kucushwa, ama-actuator e-SMA asetshenziselwa ukudala ukunyakaza kwamagagasi ngokulingisa ukunyakaza kwezinhlanzi, (d) Ama-actuator e-SMA asetshenziselwa ukwakha irobhothi lokuhlola ipayipi elincane elingasebenzisa isimiso sokunyakaza kwe-inch worm, elilawulwa ukunyakaza kwezintambo ze-SMA ngaphakathi kwesiteshi 10, (e) ikhombisa isiqondiso semicu yokufinyela yemisipha futhi ikhiqize i-contractile yemisipha ye-muscle i-SMA ikhombisa amandla emisipha ye-gastroenter. esakhiweni semisipha ye-pennate.
Ama-Actuator abe yingxenye ebalulekile yezinhlelo zemishini ngenxa yohlu olubanzi lwezinhlelo zokusebenza.Ngakho-ke, isidingo samadrayivu amancane, asheshayo futhi asebenza kahle siba sibucayi.Naphezu kwezinzuzo zabo, amadrayivu endabuko afakazele ukuthi ayabiza futhi adla isikhathi ukuwagcina.Ama-actuator e-hydraulic kanye ne-pneumatic ayinkimbinkimbi futhi ayabiza futhi angaphansi kokuguga, izinkinga zokugcoba kanye nokwehluleka kwengxenye.Ukuphendula isidingo, kugxilwe ekuthuthukiseni ama-actuator angabizi kakhulu, alungiselelwe usayizi kanye nezithuthukisiwe ngokusekelwe ezintweni ezihlakaniphile.Ucwaningo oluqhubekayo lubheka ama-activator anengqimba ye-shape memory alloy (SMA) ukuze ahlangabezane nalesi sidingo.Ama-Actuator e-Hierarchical ahlukile ngoba ahlanganisa ama-activator amaningi ahlukene abe amasistimu angaphansi kwesikali se-geometrically eyinkimbinkimbi ukuze anikeze ukusebenza okwandisiwe nokunwetshiwe.Mayelana nalokhu, izicubu zomzimba womuntu ezichazwe ngenhla zinikeza isibonelo esihle kakhulu se-multilayered actuation enjalo ene-multilayered.Ucwaningo lwamanje luchaza idrayivu ye-SMA enamazinga amaningi enezici ezimbalwa zokushayela ngakunye (izintambo ze-SMA) eziqondaniswe ne-fiber orientations ekhona emisipha ye-bimodal, ethuthukisa ukusebenza kwedrayivu kukonke.
Injongo eyinhloko ye-actuator iwukukhiqiza amandla okusebenza ngomshini njengokuphoqa nokugudluza ngokuguqula amandla kagesi.Ama-alloys enkumbulo yomumo ayikilasi lezinto "ezihlakaniphile" ezingabuyisela isimo sazo emazingeni okushisa aphezulu.Ngaphansi kwemithwalo ephezulu, ukukhuphuka kwezinga lokushisa kwentambo ye-SMA kuholela ekululameni kwesimo, okuholela ekukhuleni kwamandla okusebenza okuphezulu uma kuqhathaniswa nezinto ezihlukahlukene ezihlakaniphile eziboshwe ngokuqondile.Ngesikhathi esifanayo, ngaphansi kwemithwalo yemishini, ama-SMA aba brittle.Ngaphansi kwezimo ezithile, umthwalo we-cyclic ungamunca futhi ukhulule amandla emishini, okubonisa izinguquko zomumo we-hysteretic ohlehliswayo.Lezi zakhiwo ezihlukile zenza i-SMA ibe ilungele izinzwa, i-vibration damping futhi ikakhulukazi ama-actuator12.Unalokhu emqondweni, kube nocwaningo oluningi kumadrayivu asuselwa ku-SMA.Kufanele kuqashelwe ukuthi ama-actuator asekelwe ku-SMA aklanyelwe ukuhlinzeka ngokunyakaza kokuhumusha nokujikelezayo kwezinhlelo zokusebenza ezihlukahlukene13,14,15.Nakuba amanye ama-activator ajikelezayo enziwe, abacwaningi banentshisekelo ikakhulukazi kuma-activator aqondile.Lawa ma-actuator angahlukaniswa abe izinhlobo ezintathu zama-actuator: ama-actuator anohlangothi olulodwa, okushintshayo kanye nama-activator ahlukene 16.Ekuqaleni, amadrayivu ayi-hybrid adalwe ahlanganiswe ne-SMA namanye amadrayivu ajwayelekile.Esinye isibonelo esinjalo se-SMA-based hybrid linear actuator ukusetshenziswa kwentambo ye-SMA enenjini ye-DC ukuze inikeze amandla okukhiphayo acishe abe ngu-100 N kanye nokufuduka okubalulekile17.
Enye yentuthuko yokuqala kumadrayivu asekelwe ngokuphelele ku-SMA kwaba i-SMA parallel drive.Isebenzisa izintambo eziningi ze-SMA, idrayivu ehambisanayo esekwe ku-SMA yakhelwe ukukhulisa amandla okushayela ngokubeka zonke izintambo ze-SMA18 ngokuhambisana.Ukuxhumeka okuhambisanayo kwama-actuator akudingi nje amandla amaningi, kodwa futhi kukhawulela amandla okukhipha ucingo olulodwa.Okunye okungalungile kwama-actuator asekelwe ku-SMA uhambo olulinganiselwe abangalufinyelela.Ukuze kuxazululwe le nkinga, kwadalwa induku yekhebula ye-SMA equkethe i-beam eguquguqukayo eguquguqukayo ukuze kukhuliswe ukugudluka futhi kuzuzwe ukunyakaza okuqondile, kodwa akuzange kukhiqize amandla aphezulu19.Izakhiwo ezithambile nezindwangu zamarobhothi ezisuselwe kuma-alloys enkumbulo yomumo zenzelwe ngokuyinhloko ukukhulisa umthelela20,21,22.Kuzinhlelo zokusebenza lapho isivinini esikhulu sidingeka khona, amaphampu ashayelwa ngokuhlangene abikwe kusetshenziswa ama-SMA efilimu emincane yezinhlelo zokusebenza eziqhutshwa yi-micropump23.Imvamisa yokushayela yefilimu encane ye-SMA membrane iyisici esibalulekile ekulawuleni isivinini somshayeli.Ngakho-ke, ama-SMA linear motors anempendulo engcono eguqukayo kune-SMA spring noma ama-rod motors.Amarobhothi athambile kanye nobuchwepheshe bokubambelela ezinye izinhlelo ezimbili ezisebenzisa ama-actuator asuselwa ku-SMA.Isibonelo, ukufaka esikhundleni se-actuator evamile esetshenziswe ku-clamp yesikhala engu-25 N, i-shape memory alloy parallel actuator 24 yasungulwa.Kwesinye isimo, i-actuator ethambile ye-SMA yakhiwe ngokusekelwe ocingweni olune-matrix eshumekiwe ekwazi ukukhiqiza amandla amakhulu okudonsa angu-30 N. Ngenxa yezakhiwo zawo zokukhanda, ama-SMA aphinde asetshenziswe ukukhiqiza ama-actuator alingisa izenzakalo zebhayoloji.Enye yentuthuko enjalo ihlanganisa irobhothi elinamaseli angu-12 eliyi-biomimetic yento ephilayo efana ne-earthworm ene-SMA ukuze ikhiqize ukunyakaza kwe-sinusoidal ku-fire26,27.
Njengoba kushiwo ngaphambili, kunomkhawulo wamandla amakhulu angatholwa kuma-actuator akhona asekelwe ku-SMA.Ukubhekana nalolu daba, lolu cwaningo luveza ukwakheka kwemisipha ye-biomimetic bimodal.Ishayelwa yintambo yealloy yenkumbulo yomumo.Ihlinzeka ngesistimu yokuhlukanisa ehlanganisa izintambo ezimbalwa ze-alloy memory.Kuze kube manje, awekho ama-actuator asekelwe ku-SMA anesakhiwo esifanayo esibikiwe ezincwadini.Lolu hlelo oluyingqayizivele nolunoveli olusekelwe ku-SMA lwathuthukiswa ukuze lufunde ukuziphatha kwe-SMA ngesikhathi sokuqondisa kwemisipha ye-bimodal.Uma kuqhathaniswa nama-actuator asekelwe ku-SMA akhona, inhloso yalolu cwaningo kwakuwukudala i-biomimetic dipvalerate actuator ukuze kukhiqizwe amandla aphezulu kakhulu ngevolumu encane.Uma kuqhathaniswa namadrayivu ajwayelekile e-stepper motor asetshenziswa ezinhlelweni zokwakha ezishintshayo nokulawula kwe-HVAC, umklamo ohlongozwayo osuselwa ku-SMA-based bimodal drive wehlisa isisindo sendlela yokushayela ngama-67%.Kulokhu okulandelayo, amagama athi “imisipha” nelithi “shayela” asetshenziswa ngokufana.Lolu cwaningo luphenya ukulingiswa kwe-multiphysics kwedrayivu enjalo.Ukuziphatha kwemishini kwamasistimu anjalo kuhlolisiswe ngezindlela zokuhlola nezokuhlaziya.Ukusatshalaliswa kwamandla kanye nezinga lokushisa kwaphenywa futhi ngevolthi yokufaka engu-7 V. Kamuva, ukuhlaziya ipharamethikhi kwenziwa ukuze kuqondwe kangcono ubudlelwano phakathi kwamapharamitha angukhiye namandla okukhiphayo.Okokugcina, ama-actuator e-hierarchical aye acatshangwa futhi imiphumela yezinga eliphezulu iye yahlongozwa njengendawo engaba khona yesikhathi esizayo yama-actuator angewona ama-magnetic wezinhlelo zokusebenza zokufakelwa.Ngokwemiphumela yezifundo ezishiwo ngenhla, ukusetshenziswa kokwakhiwa kwesiteji esisodwa kukhiqiza amandla okungenani izikhathi ezine kuya kahlanu kunama-actuator asekelwe ku-SMA okubikiwe.Ukwengeza, amandla okushayela afanayo akhiqizwa idrayivu enamazinga amaningi wamazinga amaningi aboniswe ukuthi aphindwe izikhathi ezingaphezu kweshumi kunamadrayivu avamile asekelwe ku-SMA.Ucwaningo lube selubika amapharamitha abalulekile kusetshenziswa ukuhlaziya ukuzwela phakathi kwemiklamo ehlukene nokuguquguquka kokufaka.Ubude bokuqala bentambo ye-SMA (\(l_0\)), i-engeli ephinane (\(\alpha\))) kanye nenani lemicu eyodwa (n) kumucu ngamunye ngamunye kunomthelela omubi onamandla kubukhulu bamandla okushayela.amandla, kuyilapho i-voltage yokufaka (amandla) ibonakale ihlotshaniswa kahle.
Intambo ye-SMA ibonisa umphumela wenkumbulo yokuma (i-SME) ebonwa kumndeni we-nickel-titanium (Ni-Ti) wama-alloys.Ngokuvamile, ama-SMA abonisa izigaba ezimbili ezincike kuzinga lokushisa: isigaba sezinga lokushisa eliphansi kanye nesigaba sokushisa esiphezulu.Zombili izigaba zinezakhiwo eziyingqayizivele ngenxa yokuba khona kwezinhlaka zekristalu ezahlukene.Esigabeni se-austenite (isigaba sokushisa esiphezulu) esikhona ngaphezu kwezinga lokushisa lokuguqulwa, izinto ezibonakalayo zibonisa amandla aphezulu futhi zikhubazekile kabi ngaphansi komthwalo.Ingxubevange iziphatha njengensimbi engagqwali, ngakho iyakwazi ukumelana nezingcindezi eziphezulu zokusebenzisa.Kusetshenziswa lesi sakhiwo se-Ni-Ti alloys, izintambo ze-SMA zitshekile ukuze zenze i-actuator.Amamodeli okuhlaziya afanelekile athuthukiswa ukuze kuqondwe izinsimbi eziyisisekelo zokuziphatha okushisayo kwe-SMA ngaphansi kwethonya lamapharamitha ahlukahlukene kanye namajometri ahlukahlukene.Kutholwe isivumelwano esihle phakathi kwemiphumela yokuhlola neyokuhlaziya.
Ucwaningo lokuhlola lwenziwe kumfanekiso oboniswe ku-Fig. 9a ukuze kuhlolwe ukusebenza kwedrayivu ye-bimodal ngokusekelwe ku-SMA.Ezimbili zalezi zakhiwo, amandla akhiqizwa idrayivu (amandla emisipha) kanye nezinga lokushisa locingo lwe-SMA (izinga lokushisa le-SMA), kukalwa ngokuhlola.Njengoba umehluko we-voltage ukhula kubo bonke ubude bentambo ekushayeleni, izinga lokushisa locingo liyakhuphuka ngenxa yomphumela wokushisa we-Joule.I-voltage yokufaka isetshenziswe emijikelezweni emibili ye-10-s (eboniswe njengamachashazi abomvu ku-Fig. 2a, b) nesikhathi sokupholisa se-15-s phakathi komjikelezo ngamunye.Amandla okuvimbela alinganiswa kusetshenziswa i-piezoelectric strain gauge, futhi ukusatshalaliswa kwezinga lokushisa kwentambo ye-SMA kwaqashwa ngesikhathi sangempela kusetshenziswa ikhamera ye-LWIR yezinga eliphezulu lesayensi (bona izici zemishini esetshenziswe kuThebula 2).ibonisa ukuthi phakathi nesigaba se-voltage ephezulu, izinga lokushisa locingo likhuphuka nge-monotonically, kodwa uma kungekho okwamanje okugelezayo, izinga lokushisa locingo liyaqhubeka nokuwa.Ekusetheni kokuhlolwa kwamanje, izinga lokushisa lentambo ye-SMA lehlile phakathi nesigaba sokupholisa, kodwa lalisengaphezu kwezinga lokushisa le-ambient.Emkhiwaneni.I-2e ibonisa isifinyezo sezinga lokushisa kuntambo ye-SMA ethathwe kukhamera ye-LWIR.Ngakolunye uhlangothi, emkhiwaneni.2a ikhombisa amandla okuvimba akhiqizwe uhlelo lokushayela.Lapho amandla emisipha edlula amandla okubuyisela entwasahlobo, ingalo enyakazayo, njengoba kuboniswe kuMfanekiso 9a, iqala ukunyakaza.Ngokushesha nje lapho ukuqalisa kuqala, ingalo enyakazayo ihlangana nenzwa, idale amandla omzimba, njengoba kuboniswe kumfanekiso.2c, d.Uma izinga lokushisa eliphezulu liseduze kokuthi \(84\,^{\circ}\hbox {C}\), amandla amakhulu abonwayo ngu-105 N.
Igrafu ibonisa imiphumela yokuhlolwa kwezinga lokushisa kwentambo ye-SMA namandla akhiqizwe i-SMA-based bimodal actuator phakathi nemijikelezo emibili.I-voltage yokufaka isetshenziswa emijikelezweni emibili eyi-10 (eboniswa njengamachashazi abomvu) nenkathi yokupholisa imizuzwana engu-15 phakathi komjikelezo ngamunye.Intambo ye-SMA esetshenziswe ekuhloleni intambo ye-Flexinol enobubanzi obungu-0.51 mm evela ku-Dynalloy, Inc. (a) Igrafu ibonisa amandla okuhlola atholwe emijikelezweni emibili, (c, d) ibonisa izibonelo ezimbili ezizimele zesenzo sama-activator angalo anyakazayo ku-PACEline CFT/5kN piezoelectric force transducer, (b) umkhawulo wezinga lokushisa obonisa iwaya ngesikhathi segrafu yonke, ikhombisa izinga lokushisa eliphezulu le-SMA phakathi nesikhathi sonke segrafu. isithombe esithathwe ocingweni lwe-SMA kusetshenziswa ikhamera ye-FLIR ResearchIR yesofthiwe ye-LWIR.Imingcele yejiyomethri ecatshangelwe ekuhlolweni inikezwe kuThebula.eyodwa.
Imiphumela yokulingisa yemodeli yezibalo kanye nemiphumela yokuhlola iqhathaniswa ngaphansi kwesimo se-voltage yokufaka engu-7V, njengoba kuboniswe ku-Fig.5.Ngokuya ngemiphumela yokuhlaziywa kwepharamethri futhi ukuze kugwenywe ukuthi kungenzeka ukushisisa ngokweqile kwentambo ye-SMA, amandla angu-11.2 W anikezwe i-actuator.Ugesi ohlelekayo we-DC wasetshenziswa ukuze unikeze i-7V njenge-voltage yokufaka, futhi i-current engu-1.6A ikalwa kuyo yonke intambo.Amandla akhiqizwa idrayivu nezinga lokushisa le-SDR liyakhuphuka uma kusetshenziswa okwamanje.Nge-voltage yokufaka engu-7V, amandla okukhipha aphezulu atholwe emiphumeleni yokulingisa kanye nemiphumela yokuhlola yomjikelezo wokuqala ngu-78 N no-96 N, ngokulandelanayo.Emjikelezweni wesibili, amandla okukhipha aphezulu esilingisa nemiphumela yokuhlola abe ngu-150 N no-105 N, ngokulandelana.Umehluko phakathi kokulinganisa amandla okuvala kanye nedatha yokuhlola kungase kube ngenxa yendlela esetshenziselwa ukukala amandla okuvalwa.Imiphumela yokuhlola eboniswe ku-fig.I-5a ihambisana nesilinganiso samandla okukhiya, nawo alinganiswa lapho shaft yokushayela ixhumene ne-PACEline CFT/5kN piezoelectric force transducer, njengoba kuboniswe kumfanekiso.2s.Ngakho-ke, lapho i-shaft yokushayela ingathintani nenzwa yamandla ekuqaleni kwendawo yokupholisa, amandla ngokushesha abe yi-zero, njengoba kuboniswe ku-Fig. 2d.Ngaphezu kwalokho, amanye amapharamitha athinta ukwakheka kwamandla emijikelezweni elandelayo amanani esikhathi sokupholisa kanye ne-coefficient of convective heat transfer emjikelezweni odlule.Kusukela emkhiwaneni.2b, kungabonakala ukuthi ngemva kwesikhathi sokupholisa sesibili esiyi-15, intambo ye-SMA ayizange ifinyelele izinga lokushisa legumbi futhi ngenxa yalokho ibe nezinga lokushisa eliphakeme lokuqala (\(40\,^{\circ }\hbox {C}\)) emjikelezweni wesibili wokushayela uma kuqhathaniswa nomjikelezo wokuqala (\(25\, ^{\circ}\hbox {C}\)).Ngakho, uma kuqhathaniswa nomjikelezo wokuqala, izinga lokushisa locingo lwe-SMA phakathi nomjikelezo wokushisa wesibili lifinyelela izinga lokushisa lokuqala le-austenite (\(A_s\)) ngaphambili futhi lihlala esikhathini soshintsho isikhathi eside, okuholela ekucindezelekeni namandla.Ngakolunye uhlangothi, ukusabalalisa kwezinga lokushisa phakathi nemijikelezo yokushisisa nokupholisa etholwe ekuhlolweni nasekulingiseni kunokufana okuphezulu kwekhwalithi nezibonelo ezivela ekuhlaziyweni kwe-thermographic.Ukuhlaziywa okuqhathanisayo kwedatha ye-SMA yezintambo ezishisayo ezivela ekuhlolweni nasekulingiseni kubonise ukuvumelana phakathi kwemijikelezo yokushisisa nokupholisa futhi ngaphakathi kokubekezelela okwamukelekayo kwedatha yokuhlola.Izinga lokushisa eliphezulu locingo lwe-SMA, elitholwe emiphumeleni yokulingisa nokuhlolwa komjikelezo wokuqala, ngu-\(89\,^{\circ }\hbox {C}\) kanye \(75\,^{\circ }\hbox { C }\, ngokulandelana ), futhi emjikelezweni wesibili izinga lokushisa eliphezulu lentambo ye-SMA ngu-\{3 {}                                                                 C                                          C  Yayo yezinga lokushisa eliphezulu izinga eliphezulu              eliphezulu  la \circ }\ hbox {C}\).Imodeli ethuthukiswe ngokuyisisekelo iqinisekisa umphumela womphumela wenkumbulo yomumo.Indima yokukhathala nokushisa ngokweqile ayizange icatshangwe kulokhu kubuyekezwa.Ngokuzayo, imodeli izothuthukiswa ukuze ifake umlando wengcindezi wentambo ye-SMA, iyenze ifaneleke kakhulu izinhlelo zokusebenza zobunjiniyela.Amandla okukhipha idrayivu kanye nezindawo zokushisa ze-SMA ezitholwe ku-Simulink block zingaphakathi kokubekezelela okuvumelekile kwedatha yokuhlola ngaphansi kwesimo se-pulse voltage input ye-7 V. Lokhu kuqinisekisa ukulunga nokuthembeka kwemodeli yezibalo ethuthukisiwe.
Imodeli yezibalo yathuthukiswa endaweni ye-MathWorks Simulink R2020b kusetshenziswa izibalo eziyisisekelo ezichazwe esigabeni Sezindlela.Emkhiwaneni.I-3b ibonisa umdwebo webhulokhi wemodeli yezibalo ye-Simulink.Imodeli yalingisa i-voltage engu-7V yokushaya njengoba kuboniswe ku-Fig. 2a, b.Amanani amapharamitha asetshenziswe ekufanisweni abhalwe kuThebula 1. Imiphumela yokulingisa izinqubo zesikhashana ethulwa kuMfanekiso 1 no-1. Izibalo 3a no-4. Kufig.I-4a,b ibonisa i-voltage engenisiwe kuntambo ye-SMA namandla akhiqizwe i-actuator njengomsebenzi wesikhathi. Ngesikhathi sokuguqulwa okuhlanekezelwe (ukushisa), lapho izinga lokushisa lentambo ye-SMA, \(T < A_s^{\prime}\) (izinga lokushisa lokuqala lesigaba se-austenite eliguquliwe), izinga lokushintsha kwengxenye yevolumu ye-martensite (\(\dot{\xi }\)) izoba nguziro. Ngesikhathi sokuguqulwa okuhlanekezelwe (ukushisa), lapho izinga lokushisa lentambo ye-SMA, \(T < A_s^{\prime}\) (izinga lokushisa lokuqala lesigaba se-austenite eliguquliwe), izinga lokushintsha kwengxenye yevolumu ye-martensite (\(\dot{\ xi }\)) izoba nguziro. Во время обратного превращения (нагрева), когда температура проволоки SMA, \(T < A_s^{\prime}\) (температура начала аустенитной модиняценные фазиковы, когда температура проволоки SMA, \(T < A_s^{\prime}\) сть изменения объемной доли мартенсита (\(\dot{\ xi }\)) будет равно нулю. Ngesikhathi sokuguqulwa okuphambene (ukushisa), lapho izinga lokushisa lentambo ye-SMA, \(T < A_s^{\prime}\) (izinga lokushisa lokuqala le-austenite elishintshiwe ngokucindezeleka), izinga lokushintsha kwengxenye yevolumu ye-martensite (\(\dot{\ xi }\ )) izoba nguziro.在反向转变（加热）过程中，当SMA 线温度\(T < A_s^{\prime}\))积分数的变化率（\(\dot{\ xi }\)) 将为零。在 反向 转变 (加热) 中 , 当 当 当 线 温度 \ (t При обратном превращении (нагреве) при температуре проволоки СПФ \(T < A_s^{\prime}\) объемной доли мартенсита (\( \dot{\ xi }\)) будет равно нулю. Ngesikhathi sokuguqulwa okuphambene (ukushisa) ekushiseni kwentambo ye-SMA \ (T < A_s ^ {\ prime}\) (izinga lokushisa le-nucleation yesigaba se-austenite, elilungiswe ngenxa yokucindezeleka), izinga lokushintsha engxenyeni yevolumu ye-martensite (\( \dot{\ xi }\)) izolingana ne-zero.Ngakho-ke, izinga lokushintsha kwengcindezi (\(\dot{\sigma}\)) lizoncika esilinganisweni sokucindezeleka (\(\dot{\epsilon}\)) kanye nezinga lokushisa (\(\dot{T} \) ) kuphela ngokusebenzisa i-equation (1).Nokho, njengoba ucingo lwe-SMA lukhula ezingeni lokushisa neziphambano (\(A_s^{\prime}\)), isigaba se-austenite siqala ukwakha, futhi (\(\dot{\xi}\)) sithathwa njengenani elinikeziwe le-equation ( 3).Ngakho-ke, izinga lokushintsha kwamandla kagesi (\(\dot{\sigma}\)) lilawulwa ngokuhlanganyela ngokuthi \(\dot{\epsilon}, \dot{T}\) kanye \(\dot{\xi}\) lilingana nelinikezwe kufomula (1).Lokhu kuchaza izinguquko ze-gradient ezibonwe ekucindezelekeni okuguquguqukayo kwesikhathi kanye namamephu aphoqelela phakathi nomjikelezo wokushisa, njengoba kuboniswe ku-Fig. 4a, b.
(a) Umphumela wokulingisa obonisa ukusatshalaliswa kwezinga lokushisa kanye nezinga lokushisa elibangelwa ingcindezi ku-SMA-based divalerate actuator.Lapho izinga lokushisa locingo liwela izinga lokushisa lenguquko ye-austenite esigabeni sokushisisa, izinga lokushisa eliguquliwe le-austenite liqala ukwanda, futhi ngokufanayo, lapho izinga lokushisa locingo liwela izinga lokushisa lokushintsha kwe-martensitic esigabeni sokupholisa, izinga lokushisa lenguquko ye-martensitic liyehla.I-SMA yemodeli yokuhlaziya yenqubo yokuqalisa.(Ukuze uthole umbono oningiliziwe wesistimu engaphansi ngayinye yemodeli ye-Simulink, bheka isigaba se-appendix sefayela lokungezelela.)
Imiphumela yokuhlaziywa kokusatshalaliswa kwepharamitha ehlukene ikhonjiswa emijikelezweni emibili ye-voltage yokufaka engu-7V (imijikelezo yokufudumala imizuzwana eyi-10 kanye nemijikelezo yokupholisa phansi eyisekhondi eyi-15).Ngenkathi u-(ac) kanye no-(e) ebonisa ukusatshalaliswa ngokuhamba kwesikhathi, ngakolunye uhlangothi, (d) kanye no-(f) ebonisa ukusatshalaliswa kwezinga lokushisa.Ezimweni ezihambisanayo zokufakwayo, ingcindezi ephezulu ebhekiwe ngu-106 MPa (ngaphansi kuka-345 MPa, amandla okukhipha intambo), amandla angu-150 N, ukukhishwa okuphezulu ngu-270 µm, kanye nengxenye encane yevolumu ye-martensitic ngu-0.91.Ngakolunye uhlangothi, ukuguqulwa kokucindezeleka kanye noshintsho engxenyeni yevolumu ye-martensite enezinga lokushisa kufana nezici ze-hysteresis.
Incazelo efanayo iyasebenza ekuguquleni okuqondile (ukupholisa) kusukela esigabeni se-austenite kuya esigabeni se-martensite, lapho izinga lokushisa le-SMA wire (T) kanye nokushisa kokuphela kwesigaba se-martensite esishintshiwe ukucindezeleka (\(M_f^{\prime}\ )) kuhle kakhulu.Emkhiwaneni.I-4d,f ibonisa ushintsho ekucindezelekeni okudaliwe (\(\sigma\)) kanye nengxenye yevolumu ye-martensite (\(\xi\)) kuntambo ye-SMA njengomsebenzi wokushintsha kwezinga lokushisa kwentambo ye-SMA (T), kuyo yomibili imijikelezo yokushayela.Emkhiwaneni.Umfanekiso 3a ubonisa ushintsho kuzinga lokushisa kwentambo ye-SMA ngokuhamba kwesikhathi kuye ngokushaya kwe-voltage okokufaka.Njengoba kungabonwa esithombeni, izinga lokushisa locingo liyaqhubeka nokukhula ngokunikeza umthombo wokushisa ku-voltage enguziro kanye nokupholisa kwe-convective okulandelayo.Ngesikhathi sokushisa, ukuguqulwa kabusha kwe-martensite kusigaba se-austenite kuqala lapho izinga lokushisa le-SMA wire (T) liwela izinga lokushisa le-austenite nucleation elilungiswe ukucindezeleka (\(A_s^{\prime}\)).Phakathi nalesi sigaba, intambo ye-SMA iyacindezelwa futhi i-actuator ikhiqiza amandla.Futhi ngesikhathi sokupholisa, lapho izinga lokushisa le-SMA wire (T) liwela izinga lokushisa le-nucleation lesigaba se-martensite esishintshiwe ukucindezeleka (\(M_s^{\prime}\)) kukhona ukuguqulwa okuhle kusuka esigabeni se-austenite kuya esigabeni se-martensite.amandla okushayela ayancipha.
Izici eziyinhloko zekhwalithi ye-bimodal drive esekelwe ku-SMA zingatholakala emiphumeleni yokulingisa.Endabeni yokufaka i-voltage pulse, izinga lokushisa locingo lwe-SMA liyakhuphuka ngenxa yomphumela wokushisa we-Joule.Inani lokuqala lengxenye yevolumu ye-martensite (\(\xi\)) isethelwe ku-1, njengoba impahla ekuqaleni isesigabeni se-martensitic ngokugcwele.Njengoba ucingo luqhubeka nokushisa, izinga lokushisa locingo lwe-SMA lidlula izinga lokushisa le-austenite nucleation elilungiswe ukucindezeleka \(A_s^{\prime}\), okuholela ekwehleni kwengxenye yevolumu ye-martensite, njengoba kuboniswe kuMfanekiso 4c.Ngaphezu kwalokho, emkhiwaneni.I-4e ikhombisa ukusatshalaliswa kwemivimbo ye-actuator ngesikhathi, nakufig.5 - amandla okushayela njengomsebenzi wesikhathi.Isistimu ehlobene yezibalo ihlanganisa izinga lokushisa, ingxenyenamba yevolumu ye-martensite, kanye nengcindezi ekhula ocingweni, okuholela ekuncipheni kwentambo ye-SMA namandla akhiqizwa i-actuator.Njengoba kuboniswe emkhiwaneni.I-4d,f, ukuhluka kwe-voltage ngezinga lokushisa nokuhluka kwengxenye yevolumu ye-martensite nezinga lokushisa kuhambisana nezici ze-hysteresis ze-SMA esimweni esilingisiwe ku-7 V.
Ukuqhathaniswa kwemingcele yokushayela kutholwe ngokuhlolwa nokubala kokuhlaziya.Izintambo zazingaphansi kwe-pulsed input voltage engu-7 V imizuzwana engu-10, bese zipholiswa phansi imizuzwana engu-15 (isigaba sokupholisa) emijikelezweni emibili.I-engeli ephiniwe isethwe ukuze ithi \(40^{\circ}\) futhi ubude bokuqala bentambo ye-SMA emlenzeni ngamunye wephinikhodi isethelwe ku-83mm.(a) Ukulinganisa amandla okushayela nge-load cell (b) Ukuqapha izinga lokushisa lentambo ngekhamera ye-infrared eshisayo.
Ukuze uqonde ithonya lamapharamitha angokwenyama emandleni akhiqizwa idrayivu, ukuhlaziywa kokuzwela kwemodeli yezibalo kumingcele ekhethiwe yomzimba kwenziwa, futhi imingcele ibalwa ngokuvumelana nethonya labo.Okokuqala, ukusampula kwamapharamitha wemodeli kwenziwa kusetshenziswa izimiso zedizayini zokuhlola ezilandela ukusatshalaliswa okufanayo (bona Isigaba Esingeziwe Sokuhlaziya Ukuzwela).Kulesi simo, amapharamitha wemodeli afaka i-voltage yokufaka (\(V_{in}\)), ubude bentambo ye-SMA yokuqala (\(l_0\)), i-engeli engunxantathu (\(\alpha\)), i-bias spring constant (\( K_x\ )), i-convective heat transfer coefficient (\(h_T\)) kanye nenombolo yamagatsha afanayo (n).Esinyathelweni esilandelayo, amandla emisipha ephakeme kakhulu akhethwa njengemfuneko yedizayini yocwaningo futhi imiphumela ye-parametric yesethi ngayinye yeziguquguquko emandleni yatholwa.Iziqephu zenkanyamba zokuhlaziya ukuzwela zithathwe kuma-coefficients wokuxhumanisa wepharamitha ngayinye, njengoba kuboniswe ku-Fig. 6a.
(a) Amanani e-coefficient yokuhlobanisa amapharamitha emodeli nomthelela wawo kumandla amakhulu okukhiphayo wamaqembu ahlukile angu-2500 wamapharamitha wemodeli angenhla aboniswa esakhiweni senkanyamba.Igrafu ibonisa ukuhlobana kwezinga kwezinkomba ezimbalwa.Kuyacaca ukuthi \(V_{in}\) iyona kuphela ipharamitha enokuxhumana okuhle, futhi \(l_0\) iyipharamitha enokuxhumana okunegethivu okuphezulu kakhulu.Umthelela wamapharamitha ahlukahlukene ezinhlanganisela ezihlukahlukene ekuqineni kwemisipha ephakeme kakhulu uboniswa kokuthi (b, c).\(K_x\) ububanzi busuka ku-400 kuye ku-800 N/m futhi n ububanzi busuka ku-4 kuye ku-24. I-Voltage (\(V_{in}\)) ishintshile ukusuka ku-4V ukuya ku-10V, ubude bentambo (\(l_{0 } \)) bushintshile ukusuka ku-40 ukuya ku-100 mm, kanye ne-engeli yomsila (\) ( ^ ^\ alpha \ , 2, ^\ alpha) ).
Emkhiwaneni.I-6a ibonisa icebo lenkanyamba lama-coefficients ahlukahlukene okuxhumana kupharamitha ngayinye enezidingo zomklamo wamandla okushayela okuphezulu.Kusukela emkhiwaneni.6a kungabonakala ukuthi ipharamitha ye-voltage (\(V_{in}\)) ihlobene ngokuqondile namandla okukhiphayo aphezulu, kanye ne-coefficient yokudlulisa ukushisa kwe-convective (\(h_T\)), i-flame angle (\ (\alpha\)) , i-spring constant ehlala njalo (\(K_x\)) ihlotshaniswa kabi namandla okukhiphayo kanye nobude bokuqala be-SMA nobude be-mo (inombolo ye-mo) ye-ni__(l) ibonisa ukuhlobana okuqinile okuphambene Endabeni yokuhlobana okuqondile Endabeni yenani eliphakeme le-coefficient ye-voltage coefficient (\(V_ {in}\)) ibonisa ukuthi le parameter inomphumela omkhulu ekuphumeni kwamandla.Okunye ukuhlaziya okufanayo kulinganisa amandla aphezulu ngokuhlola umphumela wamapharamitha ahlukene ezinhlanganisela ezahlukene zezikhala ezimbili zokubala, njengoba kuboniswe ku-Fig. 6b, c.\(V_{in}\) kanye \(l_0\), \(\alpha\) kanye \(l_0\) zinamaphethini afanayo, futhi igrafu ibonisa ukuthi \(V_{in}\) kanye \(\alpha\ ) kanye \(\alpha\) banamaphethini afanayo.Amanani amancane \(l_0\) abangela amandla aphezulu aphezulu.Ezinye iziqephu ezimbili zihambisana noMfanekiso 6a, lapho u-n kanye \(K_x\) ehlotshaniswa kabi futhi \(V_{in}\) ehlotshaniswa kahle.Lokhu kuhlaziya kusiza ukuchaza nokulungisa imingcele enomthelela lapho amandla okukhiphayo, ukushaywa kanye nokusebenza kahle kwesistimu yokushayela kungashintshwa ukuze kuhambisane nezidingo kanye nokusetshenziswa.
Umsebenzi wamanje wocwaningo wethula futhi uphenye amadrayivu e-hierarchical anamazinga angu-N.Esigabeni sokulandelana samazinga amabili, njengoba kuboniswe ku-Fig. 7a, lapho esikhundleni sentambo ngayinye ye-SMA ye-actuator yeleveli yokuqala, ukuhlelwa kwe-bimodal kufinyelelwa, njengoba kuboniswe kumfanekiso.9e.Emkhiwaneni.I-7c ibonisa ukuthi intambo ye-SMA ilinyazwe kanjani engalweni egudlukayo (ingalo eyinsiza) ehamba kuphela ohlangothini longitudinal.Nokho, ingalo eyinhloko enyakazayo iyaqhubeka nokunyakaza ngendlela efanayo nengalo enyakazayo yesiteji sokuqala se-actuator enezigaba eziningi.Ngokuvamile, idrayivu ye-N-stage idalwe ngokufaka esikhundleni sentambo ye-SMA ethi \(N-1\) ngedrayivu yesigaba sokuqala.Ngenxa yalokho, igatsha ngalinye lilingisa idrayivu yesiteji sokuqala, ngaphandle kwegatsha elibamba ucingo ngokwalo.Ngale ndlela, izakhiwo ezifakwe isidleke zingakhiwa ezidala amandla amakhulu izikhathi eziningana kunamandla okushayela okuyinhloko.Kulolu cwaningo, ezingeni ngalinye, ubude bezintambo ze-SMA obuphelele obuyi-1 m bucatshangelwe, njengoba kuboniswe kufomethi yethebula ku-Fig. 7d.Amanje ngocingo ngalunye ekwakhiweni ngakunye ngakunye kanye nomphumela we-prestress namandla kagesi engxenyeni ngayinye yocingo lwe-SMA kuyafana kuleveli ngayinye.Ngokusho kwemodeli yethu yokuhlaziya, amandla okukhiphayo ahlotshaniswa kahle nezinga, kuyilapho ukususwa kuhlotshaniswa kabi.Ngesikhathi esifanayo, kwakukhona ukuhwebelana phakathi kokuhamba kanye namandla emisipha.Njengoba kubonakala emkhiwaneni.7b, kuyilapho amandla amakhulu afinyelelwa enanini elikhulu kakhulu lezendlalelo, ukugudluzwa okukhulu kunakho konke kubonwa kungqimba oluphansi kakhulu.Lapho izinga le-hierarchy lisethwa ukuze lithi \(N=5\), amandla emisipha aphezulu angu-2.58 kN atholwe nemivimbo emi-2 ebhekiwe \(\upmu\)m.Ngakolunye uhlangothi, idrayivu yesiteji sokuqala ikhiqiza amandla angu-150 N ngokushaya okungu-277 \(\upmu\)m.Ama-actuator anamazinga amaningi akwazi ukulingisa imisipha yangempela yebhayoloji, lapho imisipha yokwenziwa esekelwe kuma-alloys enkumbulo yomumo ikwazi ukukhiqiza amandla aphakeme kakhulu ngokunyakaza okunembayo nokucolekile.Imikhawulo yalo mklamo omncane ukuthi njengoba ubuholi bukhula, ukunyakaza kuncipha kakhulu futhi inkimbinkimbi yenqubo yokukhiqiza idrayivu iyanda.
(a) Uhlelo lwe-actuator olunezigaba ezimbili (\(N=2\)) lwenkumbulo yomumo we-alloy luboniswa ekucushweni kwe-bimodal.Imodeli ehlongozwayo ifinyelelwa ngokushintsha intambo ye-SMA esigabeni sokuqala se-actuator enezingqimba ngesinye i-actuator enesiteji esisodwa.(c) Ukumiswa okukhubazekile kwesiteji sesibili se-actuator yezigaba eziningi.(b) Ukusatshalaliswa kwamandla kanye nokugudluzwa kuye ngenani lamazinga kuchaziwe.Kutholwe ukuthi amandla aphezulu e-actuator ahlotshaniswa kahle nezinga lesilinganiso kugrafu, kuyilapho ukushaywa kuhlotshaniswa kabi neleveli yesikali.I-voltage yamanje kanye ne-pre-voltage kuntambo ngayinye ihlala ingashintshi kuwo wonke amaleveli.(d) Ithebula libonisa inombolo yompompi kanye nobude bentambo ye-SMA (fiber) kuleveli ngayinye.Izici zezintambo ziboniswa ngenkomba 1, futhi inombolo yamagatsha esibili (eyodwa exhunywe emlenzeni oyinhloko) iboniswa inombolo enkulu kunazo zonke ekubhaliseni.Isibonelo, ezingeni 5, \(n_1\) ibhekisela enanini lezintambo ze-SMA ezikhona kusakhiwo ngasinye se-bimodal, futhi \(n_5\) ibhekisela enanini lemilenze eyisizayo (exhunywe emlenzeni omkhulu).
Izindlela ezihlukahlukene ziye zahlongozwa abacwaningi abaningi ukuze benze imodeli yokuziphatha kwama-SMA ngenkumbulo yomumo, encike ezicini ze-thermomechanical ezihambisana nezinguquko ze-macroscopic esakhiweni sekristalu esihambisana noshintsho lwesigaba.Ukwakhiwa kwezindlela eziyisisekelo kuyinkimbinkimbi ngokwemvelo.Imodeli ye-phenomenological esetshenziswa kakhulu ihlongozwa yi-Tanaka28 futhi isetshenziswa kakhulu ezinhlelweni zobunjiniyela.Imodeli ye-phenomenological ephakanyiswe u-Tanaka [28] ithatha ukuthi ingxenye yevolumu ye-martensite iwumsebenzi ocacile wokushisa nokucindezeleka.Kamuva, u-Liang no-Rogers29 kanye no-Brinson30 bahlongoza imodeli lapho ukuguquguquka kwesigaba kwakucatshangwa ukuthi kuwumsebenzi we-cosine we-voltage kanye nezinga lokushisa, nokuguqulwa okuncane kumodeli.U-Becker no-Brinson bahlongoze umdwebo wesigaba osuselwe kumodeli ye-kinetic ukuze ubonise ukuziphatha kwezinto ze-SMA ngaphansi kwezimo zokulayisha ngokunganaki kanye noshintsho olungaphelele.I-Banerjee32 isebenzisa indlela ye-dynamics yesigaba se-Bekker kanye ne-Brinson31 ukuze ilingise izinga elilodwa lokukhohlisa inkululeko elithuthukiswe ngu-Elahinia no-Ahmadian33.Izindlela ze-Kinetic ezisekelwe emidwebeni yesigaba, ezicabangela ukuguqulwa kwe-nonmonotonic ku-voltage enezinga lokushisa, kunzima ukuzisebenzisa ezinhlelweni zobunjiniyela.U-Elakhinia no-Ahmadian badonsela ukunaka kulokhu kushiyeka kwamamodeli we-phenomenological akhona futhi baphakamise imodeli ye-phenomenological enwetshiwe ukuze kuhlaziywe futhi kuchazwe ukuziphatha kwenkumbulo yomumo ngaphansi kwanoma yiziphi izimo zokulayisha eziyinkimbinkimbi.
Imodeli yesakhiwo yentambo ye-SMA inika ingcindezi (\(\sigma\)), uhlobo (\(\epsilon\)), izinga lokushisa (T), kanye nengxenye yevolumu ye-martensite (\(\xi\)) yentambo ye-SMA.Imodeli ye-phenomenological constitutive yaqale yahlongozwa ngu-Tanaka28 futhi kamuva yamukelwa ngu-Liang29 kanye no-Brinson30.Okuphuma kokunye kwesibalo kunefomu:
lapho u-E eyimoduli ye-SMA Young encike esigabeni etholwe kusetshenziswa \(\isitayela sokubonisa E=\xi E_M + (1-\xi )E_A\) kanye ne-\(E_A\) kanye \(E_M\) emelela i-Young's modulus ziyizigaba ze-austenitic ne-martensitic, ngokulandelana, kanye ne-coefficient ye-therta expansion (i-T\).Isici somnikelo wenguquko yesigaba sithi \(\Omega = -E \epsilon _L\) futhi \(\epsilon _L\) iwuhlobo lohlobo oluningi olubuyisekayo ocingweni lwe-SMA.
Izibalo ze-dynamics zesigaba ziqondana nomsebenzi we-cosine othuthukiswe ngu-Liang29 futhi kamuva wamukelwa i-Brinson30 esikhundleni somsebenzi womchazi ohlongozwa i-Tanaka28.Imodeli yenguquko yesigaba iyisandiso semodeli ehlongozwe u-Elakhinia kanye no-Ahmadian34 futhi yalungiswa ngokusekelwe ezimweni zenguquko zesigaba ezinikezwe uLiang29 noBrinson30.Izimo ezisetshenziselwa le modeli yenguquko yesigaba zivumelekile ngaphansi kwemithwalo ye-thermomechanical eyinkimbinkimbi.Esikhathini ngasinye sesikhathi, inani lengxenye yevolumu ye-martensite liyabalwa lapho kwenziwa imodeli yezibalo ezihlanganisayo.
I-equation ebusayo yokuguqulwa kabusha, evezwa ukuguqulwa kwe-martensite ukuze i-austenite ngaphansi kwezimo zokushisa, imi kanje:
lapho i-\(\xi\) iyingxenyana yevolumu ye-martensite, \(\xi _M\) iyingxenyana yevolumu ye-martensite etholwe ngaphambi kokushisisa, \(\displaystyle a_A = \pi /(A_f – A_s)\), \ ( \displaystyle b_A = -a_A/C_A\) kanye \(C_A\) - ijika (smater \ _wire) - ijika le-SMA (i-wire _A_S) _f\) - ukuqala nokuphela kwesigaba se-austenite, ngokulandelana, izinga lokushisa.
I-equation yokulawula ukuguqulwa okuqondile, emelwe ukuguqulwa kwesigaba se-austenite kuya ku-martensite ngaphansi kwezimo zokupholisa, yile:
lapho i-\(\xi _A\) iyingxenyana yevolumu ye-martensite etholwe ngaphambi kokupholisa, \(\displaystyle a_M = \pi /(M_s – M_f)\), \(\displaystyle b_M = -a_M/C_M\) kanye \ ( C_M \) - imingcele yokufaka ijika, T - SMA izintambo zokushisa - M_ izinga lokushisa, i-marvement_final \) (izintambo zokushisa ze-M__) ly.
Ngemva kokuba izibalo (3) kanye (4) zihlukanisiwe, izibalo eziguquguqukayo eziphambene neziqondile zenziwa lula zibe yifomu elilandelayo:
Ngesikhathi soshintsho oluya phambili nangemuva \(\eta _{\sigma}\) kanye \(\eta _{T}\) kuthatha amanani ahlukene.Izibalo eziyisisekelo ezihlotshaniswa ne-\(\eta _{\sigma}\) kanye \(\eta _{T}\) zitholiwe futhi kwaxoxwa ngazo ngokuningiliziwe esigabeni esengeziwe.
Amandla ashisayo adingekayo ukuphakamisa izinga lokushisa kwentambo ye-SMA avela kumphumela wokushisa we-Joule.Amandla ashisayo amuncwa noma akhishwe intambo ye-SMA amelelwa ukushisa okucashile koshintsho.Ukulahlekelwa ukushisa ocingweni lwe-SMA kungenxa yokuguqulwa okuphoqelelwe, futhi uma kubhekwa umthelela onganakwa wemisebe, ibhalansi yebhalansi yamandla okushisa imi kanje:
Lapho \(m_{wire}\) okuyisamba esiphelele sentambo ye-SMA, \(c_{p}\) amandla athile okushisa e-SMA, \(V_{in}\) i-voltage esetshenziswa ocingweni, \(R_{ohm} \ ) - ukumelana nesigaba se-SMA, okuchazwa ngokuthi;\(R_{ohm} = (l/A_{cross})[\xi r_M + (1-\xi )r_A]\ ) lapho \(r_M\ ) kanye \(r_A\) kuyisigaba se-SMA resistivity ku-martensite ne-austenite, ngokulandelana, \(A_{c}\) indawo engaphezulu ye-SMA wire is a H (\) imemori ye-SMA.Ukushisa okucashile koshintsho lwentambo, i-T kanye \(T_{\infty}\) izinga lokushisa lentambo ye-SMA nendawo ezungezile, ngokulandelanayo.
Lapho ucingo lwengxubevange yenkumbulo yomumo lusebenza, intambo iyaminyanisa, idale amandla egatsheni ngalinye lomklamo we-bimodal okuthiwa i-fiber force.Amandla ezintambo ku-strand ngayinye yocingo lwe-SMA ndawonye adala amandla emisipha ukuze asebenze, njengoba kuboniswe ku-Fig. 9e.Ngenxa yokuba khona kwesiphethu esichemile, ingqikithi yamandla emisipha ye-Nth multilayer actuator ithi:
Ukufaka esikhundleni \(N = 1\) ku-equation (7), amandla emisipha wesigaba sokuqala se-bimodal drive prototype angatholakala kanje:
lapho u-n eyinombolo yemilenze e-unimodal, \(F_m\) amandla emisipha akhiqizwa ukushayela, \​(F_f\) amandla e-fiber ocingweni lwe-SMA, \(K_x\) ukuqina okuchema.intwasahlobo, \(\alpha\) i-engeli kanxantathu, \(x_0\) iwukusuka kokuqala kwentwasahlobo yokuchema ukuze ibambe ikhebula le-SMA lisesimweni esicindezelekile ngaphambili, futhi \(\Delta x\) uhambo lwe-actuator.
Ukususwa okuphelele noma ukunyakaza kwedrayivu (\(\Delta x\)) kuye nge-voltage (\(\sigma\)) kanye nobunzima (\(\epsilon\)) ocingweni lwe-SMA lwesiteji se-Nth, idrayivu isethelwe ku- (bona Fig. ingxenye eyengeziwe yokuphumayo):
Izibalo ze-kinematic zinikeza ubudlelwano phakathi kokuguqulwa kwedrayivu (\(\epsilon\)) nokugudluzwa noma ukususwa (\(\Delta x\)).Ukuguqulwa kwentambo ye-Arb njengomsebenzi wobude bocingo lwe-Arb lokuqala (\(l_0\)) nobude bentambo (l) noma kunini t egatsheni elilodwa elingashintshiwe kanje:
lapho \(l = \sqrt{l_0^2 +(\Delta x_1)^2 – 2 l_0 (\Delta x_1) \cos \alpha _1}\) itholakala ngokusebenzisa ifomula ye-cosine kokuthi \(\Delta\)ABB ', njengoba kubonisiwe kuMfanekiso 8. Okwesiteji sokuqala sokushayela (\(N)\\\\ De\\\\\\\\\\\\\\\n\n\n\n\n\n), njengoba kubonisiwe kuMdwebo 8. Esiteji sokuqala sokushayela (\(N) =\ futhi \(\ alpha _1\) ithi \(\alpha \) njengoba kuboniswe kuMfanekiso 8, ngokuhlukanisa isikhathi ukusuka ku-Equation (11) nokufaka esikhundleni senani lika-l, izinga lobunzima lingabhalwa ngokuthi:
lapho \(l_0\) kuwubude bokuqala bentambo ye-SMA, l ubude bentambo nganoma isiphi isikhathi t egatsheni elilodwa elingashintshiwe, \(\epsilon\) iwukuwohloka okwakhiwa ocingweni lwe-SMA, futhi \(\alpha \) i-engeli kanxantathu , \(\Delta x\) i-drive offset (njengoba kuboniswe kuMfanekiso 8).
Zonke n izakhiwo ezinesiqongo esisodwa (\(n=6\) kulo mfanekiso) zixhunywe ochungechungeni lokuthi \(V_{in}\) njenge-voltage yokufaka.Isiteji I: Umdwebo oyisikimu wentambo ye-SMA ekucushweni kwe-bimodal ngaphansi kwezimo ze-voltage enguziro Isigaba II: Isakhiwo esilawulwayo siyaboniswa lapho intambo ye-SMA icindezelwa khona ngenxa yokuguqulwa okuphambene, njengoba kuboniswa umugqa obomvu.
Njengobufakazi bomqondo, idrayivu ye-bimodal esekelwe ku-SMA yathuthukiswa ukuze kuhlolwe ukutholwa okulingisiwe kwezibalo eziyisisekelo ngemiphumela yokuhlola.Imodeli ye-CAD ye-actuator yomugqa we-bimodal ikhonjisiwe ku-fig.9a.Ngakolunye uhlangothi, emkhiwaneni.I-9c ibonisa idizayini entsha ehlongozwayo yoxhumo oluzungezayo lwe-prismatic kusetshenziswa i-actuator esekelwe izindiza ezimbili ze-SMA enokwakheka kwe-bimodal.Izingxenye zedrayivu zakhiwe kusetshenziswa ukukhiqiza okungeziwe kuphrinta ye-Ultimaker 3 Extended 3D.Izinto ezisetshenziselwa ukuphrinta izingxenye ze-3D yi-polycarbonate elungele izinto ezimelana nokushisa njengoba iqinile, ihlala isikhathi eside futhi inezinga lokushisa eliphezulu lokushintsha kwengilazi (110-113 \(^{\circ }\) C).Ngaphezu kwalokho, i-Dynalloy, Inc. i-Flexinol shape memory alloy wire yasetshenziswa ekuhlolweni, futhi izakhiwo zezinto ezibonakalayo ezihambisana ne-Flexinol wire zisetshenziswe ekufaniseni.Izintambo eziningi ze-SMA zihlelwa njengemicu ekhona ekuhlelweni kwe-bimodal yemisipha ukuze zithole amandla aphezulu akhiqizwa ama-actuator amaningi, njengoba kuboniswe ku-Fig. 9b, d.
Njengoba kukhonjisiwe kuMfanekiso 9a, i-engeli ebukhali eyakhiwe ucingo lwe-SMA engalweni enyakazayo ibizwa nge-engeli (\(\alpha\)).Ngezinsimbi zetheminali ezinamathiselwe kuma-clamps kwesokunxele nakwesokudla, intambo ye-SMA ibanjwe nge-engeli efiswayo ye-bimodal.Idivayisi yentwasahlobo echemile ebanjwe kusixhumi sasentwasahlobo idizayinelwe ukulungisa amaqembu ahlukene esandiso sentwasahlobo achemile ngokuya ngenombolo (n) yamafayibha e-SMA.Ngaphezu kwalokho, indawo yezingxenye ezihambayo iklanywe ngendlela yokuthi ucingo lwe-SMA luvezwe endaweni yangaphandle ukuze luphole ngokuphoqwa kwe-convection.Amapuleti aphezulu naphansi enhlanganisela ekhiphekayo asiza ukugcina intambo ye-SMA ipholile ngokusikwa okukhishiwe okudizayinelwe ukunciphisa isisindo.Ukwengeza, zombili iziphetho zocingo lwe-CMA zinamathele kumatheminali angakwesokunxele nangakwesokudla, ngokulandelana, ngokusebenzisa i-crimp.I-plunger ixhunywe ekugcineni komhlangano osusekayo ukuze kugcinwe imvume phakathi kwamapuleti aphezulu naphansi.I-plunger iphinde isetshenziselwe ukusebenzisa amandla okuvimbela kunzwa ngokuthintana naye ukuze kulinganiswe amandla okuvimba lapho intambo ye-SMA icushiwe.
Isakhiwo semisipha ye-bimodal SMA ixhunywe ngogesi ochungechungeni futhi inikwa amandla yi-voltage ye-pulse input.Ngesikhathi somjikelezo we-voltage pulse, lapho i-voltage isetshenziswa futhi ucingo lwe-SMA lushiswa ngaphezu kwezinga lokushisa lokuqala le-austenite, ubude bocingo ku-strand ngayinye bufushane.Lokhu kuhlehlisa kwenza kusebenze i-arm subassembly egudlukayo.Lapho i-voltage ineziro kumjikelezo ofanayo, intambo eshisayo ye-SMA yapholiswa ngaphansi kwezinga lokushisa lendawo ye-martensite, ngaleyo ndlela ibuyela endaweni yayo yasekuqaleni.Ngaphansi kwezimo ze-zero zengcindezi, intambo ye-SMA iqale yelulwe ngokungenzi lutho ngesiphethu se-bias ukuze ifinyelele esimweni se-martensitic ehlisiwe.Isikulufu, lapho kudlula khona intambo ye-SMA, sinyakaza ngenxa yokucindezelwa okudalwe ngokusebenzisa i-voltage pulse ocingweni lwe-SMA (i-SPA ifinyelela esigabeni se-austenite), okuholela ekusebenzeni kwe-lever ehambayo.Lapho intambo ye-SMA ihoxiswa, isiphethu sokuchema sidala amandla aphikisayo ngokuqhubeka nokwelula intwasahlobo.Lapho ingcindezi ku-voltage yomfutho iba nguziro, intambo ye-SMA iyanwebeka futhi ishintshe ukuma kwayo ngenxa yokupholisa kwe-convection ngempoqo, ifinyelele esigabeni se-martensitic ephindwe kabili.
Uhlelo oluhlongozwayo lwe-SMA-based linear actuator lunokucushwa kwe-bimodal lapho izintambo ze-SMA zi-engeli.(a) ibonisa imodeli ye-CAD yomfanekiso, esho ezinye zezingxenye nezincazelo zazo zesibonelo, (b, d) imele i-prototype yokuhlola ethuthukisiwe35.Ngenkathi (b) ibonisa ukubuka okuphezulu kwesibonelo esinezixhumi zikagesi neziphethu ezichemile namageji ohlobo olusetshenzisiwe, (d) sibonisa umbono wokubuka wokusetha.(e) Umdwebo wesistimu ye-actuation ewumugqa enezintambo ze-SMA ezibekwe kabili noma kunini t, obonisa isiqondiso nendlela yefayibha namandla emisipha.(c) Uxhumano lwe-prismatic olujikelezayo lwe-2-DOF luphakanyiswe ukuze kusetshenziswe i-actuator enezindiza ezimbili esekelwe ku-SMA.Njengoba kubonisiwe, isixhumanisi sidlulisa ukunyakaza komugqa ukusuka kudrayivu engezansi kuya engalweni ephezulu, kudala ukuxhumana okujikelezayo.Ngakolunye uhlangothi, ukunyakaza kwepheya lamaprism kuyafana nokunyakaza kwedrayivu yesiteji sokuqala se-multilayer.
Ucwaningo lokuhlola lwenziwe kumfanekiso oboniswe ku-Fig. 9b ukuze kuhlolwe ukusebenza kwedrayivu ye-bimodal ngokusekelwe ku-SMA.Njengoba kuboniswe kuMfanekiso 10a, ukusethwa kokuhlola kuhlanganisa ukunikezwa kwamandla kwe-DC okuhlelekayo ukuze kunikezwe amandla kagesi okufakwayo ezintanjeni ze-SMA.Njengoba kuboniswe emkhiwaneni.10b, i-piezoelectric strain gauge (PACEline CFT/5kN) yasetshenziswa ukukala amandla okuvimba kusetshenziswa i-Graphtec GL-2000 data logger.Idatha irekhodwa umsingathi ukuze kuqhutshekwe nocwaningo.Amageji okulinganisa kanye nezikhulisamandla zokushaja zidinga ukunikezwa kwamandla okuqhubekayo ukukhiqiza isignali kagesi.Izimpawu ezihambisanayo ziguqulwa zibe amandla okukhipha amandla ngokusho kokuzwela kwenzwa ye-piezoelectric force kanye neminye imingcele njengoba kuchazwe kuThebula 2. Uma i-voltage pulse isetshenziswa, izinga lokushisa locingo lwe-SMA liyakhuphuka, okwenza ucingo lwe-SMA lucindezele, okubangela ukuthi i-actuator ikhiqize amandla.Imiphumela yokuhlolwa kokuphuma kwamandla emisipha nge-pulse voltage input ye-7 V iboniswa kufig.2a.
(a) Isistimu ye-actuator esekelwe ku-SMA yasungulwa ekuhlolweni kokulinganisa amandla akhiqizwe i-actuator.Iseli lomthwalo likala amandla okuvimbela futhi linikwa amandla ngugesi ongu-24 V DC.Ukwehla kwamandla kagesi angu-7 V kusetshenziswe kubo bonke ubude bekhebula kusetshenziswa ugesi we-GW Instek ohlelekayo we-DC.Intambo ye-SMA iyashwabana ngenxa yokushisa, futhi ingalo ephathekayo ithinta iseli lomthwalo futhi isebenzise amandla okuvimba.Iseli lokulayisha lixhunywe kusilogger sedatha ye-GL-2000 futhi idatha igcinwa kumsingathi ukuze kuqhutshekwe nokucubungula.(b) Umdwebo obonisa uchungechunge lwezingxenye zokusetha kokuhlola ukuze kukale amandla emisipha.
Ama-alloys enkumbulo yomumo ajatshuliswa amandla ashisayo, ngakho izinga lokushisa liba ipharamitha ebalulekile yokufunda isimo senkumbulo yomumo.Ngokuhlola, njengoba kuboniswe ku-Fig. 11a, ukucabangela okushisayo nokulinganisa izinga lokushisa kwenziwa ku-prototype SMA-based divalerate actuator.Umthombo we-DC ohlelekayo usebenzise i-voltage yokufaka ezintanjeni ze-SMA ekusetheni kokuhlola, njengoba kuboniswe kuMfanekiso 11b.Ukushintsha kwezinga lokushisa kwentambo ye-SMA kukalwe ngesikhathi sangempela kusetshenziswa ikhamera ye-LWIR enesinqumo esiphezulu (FLIR A655sc).Umsingathi usebenzisa isofthiwe ye-ResearchIR ukurekhoda idatha ukuze kuqhutshekwe nokucubungula ngemva kokucubungula.Uma kusetshenziswa i-voltage pulse, izinga lokushisa locingo lwe-SMA liyakhuphuka, okwenza intambo ye-SMA inciphe.Emkhiwaneni.Umfanekiso 2b ubonisa imiphumela yokuhlolwa yezinga lokushisa lentambo ye-SMA ngokuqhathaniswa nesikhathi se-pulse ye-voltage yokufaka engu-7V.