Wearable handwriting input device using magnetic field

(1)

Wearable handwriting input device using magnetic field

著者 Han Xinying

著者別名韓, 新瑩

journal or

publication title

博士学位論文要旨論文内容の要旨および論文審査結果の要旨／金沢大学大学院自然科学研究科

volume 平成21年6月

page range 55‑59

year 2009‑06‑01

URL http://hdl.handle.net/2297/26909

(2)

氏名学位の種類学位記番号学位授与の日付学位授与の要件学位授与の題目

韓新榮博士（工学）

博甲第１０５４号平成２０年９月２６日

課程博士(学位規則第４条第１項）

ＷＥＡＲＡＢＬＥＨＡＮＤＷＲＩＴＩＮＧＩＮＰＵＴＤＥⅥＣＥＵＳＩＮＧＭＡＧＮＥＴＩＦＩＥＬＤ（磁気を利用したウエアラブル手書き文字入力デバイス）

関啓明（理工研究域・准教授）

神谷好承（理工研究域・教授)，木村春彦（理工研究域・教授)，

立矢宏（理工研究域・教授)，宮崎猛(理工研究域・准教授）

論文審査委員（主査）

論文審査委員（副査）

AZDsZmcr

hourrescarchwcproposedawearablehandwritinginputdeviceusingmagnetic fieldnlisdevicerequiresmountingapennanentmagnetontofingertipanddetecting themagneticfieldgeneratedbythemagnetthroughmagneticsensorsatthewristofthe otherhand・Thepositionofmagnetiscalculatedbythcvectorofthemagneticfieldwith geomagnetismCancellation・Wemadeprototypedeviceandsucceeｄｅｄｔｏｇｃｔｔｈｅｈａｎｄｗｒｉｔｍｇｉ叩utcharactenTheinfluenccsofmisaligmnentofmagnctandnoisein circuitareinvestigatcdbysimulationsandexperiments．

LIntmduction

Asmfbnnationtecllnologywas developedquicklylmanykindsofinput deviceshavebeendeveloped・Theymake

ourlivesmuchmorecomfOrtableand

convenient・Ｏｎｔｈｅｏｔｈｅｒｈａｎｄ，these deviceshavemanydisadvantages．］For example,keyboardistoobigtocarryand requirestrainingtogctusedtoit・Mouse ncedsaplanctooperate、Ibuchpanelis goodbutrequiresapaneltoworkon,and itsworkingspaceislimitedwithinthe paneLVirtualkeyboardneedｓａｐｌａｎｅｔｏｐｕｔｕｓｅｒ,ｓｈａｎｄｓａｎｄｈａｓｔｏｂｅｆｉｘｅｄｓｏｍｅｗｈｅｒｅ・Vbiceinputhasbeen developedgreaｔｌｙｂｕｔｉｔｄｏｃｓｎｏｔｗｏｒｋｗｅｌｌｉｎｎｏｉｓｙenvironmenｔａｎｄｎｅｅｄｓ

ｍｕｃｈｔｉｍｅｔｏｂｅｕｓｅｄｔｏｉｔ・AndfOrelder

person，post-natalvisuallyimpairedand thosewhoarenotskilledinoperationof computeLfCwdevicesarcavailable．

Filrthermore，fewdevicesaredeveloped fOrthewearablecomputing・

TherefOrewehaveproposedanew

devicetofitthedemandabove・Ｉｔｉｓａｂｌｅ

ｔｏｂｅｕｓｃｄｂｙａｌｍｏｓｔｅｖｅｒｙone,including post-natalvisuallyimpaired，peopleｗｈｏａｒｅｎｏｔｕｓｅｄｔｏｃｏｍｐｕｔｅＬａｎｄｔｈｏｓe workinginnoisyenvironmcnt・This deViceｄｏｅｓｎｏｔｎｅｅｄａｎｙｐｌａｎｅｏｒｐａｎｅｌ，

justneedstobefixedontouser,shands・

Ａｎｄｕｓｅｒｃａｎｂｅｕｓｅｄｔｏｉｔｗｉｔｈｏｕｔａｎｙ trainingevenuscrgetitjustnow．

－５５－

(3)

H(昨芸[3r響の－m］ ^（１）

Ｈｅｒｃｍｉｓｔｈｅｕｍｔｖｅｃｔｏｒｏｆｍａｇｎｅｔｉｃｍomentofmagnet,whichshouldbemCK，

y，ｚ)．misthemagneticmomentof magnet・risthelocationvectorofmagnet，

ａｎｄｉｔｓｖａｌｕｅｉｓＬｔｈｅｄｉｓｔｍｃｅｂｅｔｗｅｅn magnetandmagneticsensoL

Whenthemagnetlocatesat(x,ｙＰ)in themagneticsensororientedcoordinate，

mshouldbe(1,0,0),andrshouldbc(_x，

-ｙｐ)．

（Ｈｘ,Ｈ,,Ｈz)＝

（Ｋ・ｚｘ２－ｙ２５，３Ｋ. ^ｊＯノ _{5,0）（２）}

２．Pmposeddevice

Writil1宵charactersonpalmwith

］ｏＢＩｒＩｏｎｃ

、

Figllmageofproposeddevicc Fig､１ｓｈｏｗｓｔｈｅｗｈｏｌｅｉｍａｇｅｏｆｏｕｒｄｅｖｉｃｅ・Theinputdeviceweproposed consistsofapennanentmagnctwhichis mountedonuser，sfinger，twomagnctic sensorsandthcirperipheralcircuitsto detectthemagneticfieldsgcneratedby thcmagnet，ａｎＡ/Dconvertcrwhich convertstheoutputvoltagesignalof magneticsensorintodigitaloneto inputtocomputer，andacomputerto calculatethepositionofmagnetand visualizethehandwritingchamcteL

S･Positioningcalculation

BefOrecalculatmgthepositionof magnet，weneedtoknowthemagnetic fieldgeneratedbyit､Magnetlocatesat(x，

y)innlagncticsensororicntedcoordinate willgeneratemagneticfieldwhicllcanbe gottenbyEqs.(1)-(2).Itsinlageisshown inFigZ

（x2＋ｙ２)ｚ（x2＋y2)２

１nourdeviceweadopttwomagnetic sensorstodetectthepositionofmagnet withgeolnagnetismcancellationThe positionofmagnetcanbeyicldedbythe fO11owingcquationsthroughthe differenceofoutputsoftwomagnetic sensors・Relationshipbetweenmagnet andoutputsoftwomagneticsensorsis sｈｏｗｎｉｎＦｉｇ３・Theycanbeyieldedby Eqs.(3)-(4)

ダダ

AIllbient field

／、､②，

、シ・

ぞ:i>i、

．、

Magnetic

ｍＪ

／

ｃｆｉｅｌｄ

、０１ｓｔ孔ｃ皿ⅥＶ

分．

_ぐみ

_Magnetic

Fig.３Imageofpositioningcalculation

､叱免･口...△へ＿､▲■｡｡｡.～も．､－．－．A.．...□...づぃ..｡.＿ザ①､－－．～..←...．,ﾛﾛﾁﾞｹﾞﾁﾞｹﾞｹﾞゴタナヂグタ

、■･も.、.

Fig.２Magneticfieldgeneratedbymagnet 血`-Ｍが一二｝

^。

^（３）

[jrz+(y＋`/)2]２Cf+ゾ)２ /(（(xj)＝Ｋ･｛

－５６－

(4)

fUnctionF(x,y)〈e・

Weselect(0,0.001)astheinitialpoint inSD-methodaｎｄｐｉｓＺ,ｅｉｓｌｅ－３ｉｎｏｕｒ

ｄｅｖｉｃｅ．

刀(xウル3K.｛ｘＯＭ）ｘ)′５｝

^Ｓ

（４）

［x2＋(y+c/)2]２（xz＋y2)２

Here，Kisthecoefficientabout magneticmomcntinourdevice.(x,ｙ)is thcpositionofmagnctinmagneticsensor

Aorientedcoordinate・disthedistance betwcentwomagneticsensors・

Becauseitisdifficulttosolve

eqUations(3)-(4)，wcadoptstcepcst descentmethod（SD-method）inour system

lnSD-methodcalculationstartsatan

arbitrarypoint(xo,ｙｏ)．Wetakeaseries ofstepsuntilwearesatisfiedthatweare closeenoughtosolutionWhenwetakea step,wechoosethcdirectionof(f1x,f1y)．

Ａｎｄwcassumethatthetargetfmction

is：

３.Prototypedevice

２－axismagneticsensorHoneywell⑪

HMC-1022isadoptedinourdevice・We

exploithterface②CBI-3133BasA/D

converter、Neodymiumtypemagnet TBuchino⑪51-421isselectedtomount ontouser,sfingertip・Wedcsigneda

mounterfOrit．Ｃ＆DIbchnologies③

ＮＭＡＯ５０５Ｓｉｓｕｓｅｄｉｎｏｕｒｄｅｖｉｃｅａｓ

ｐｏｗersupplymodule、ＴｈｅＰＣＢｏｆｏｕｒｄｅｖｉｃｅｉｓｓｈｏｗｎｉｎＦｉｇ４Ａ/Dconverter，

powersupplymoduleandcomputerare notincludedinthephotos・ＴｈｅＰＣＢｉｓｍｏｕｎｔｅｄｏｎｔｈｅｗｒｉｓｔｂｙａｍｏunter6

F(x,)ﾉ)-Z?(x,)')+矛(〃） ⁽⁵⁾

Firstlyweselectanarbitrarypoint(xo，

yo)，andcalculatethetargetfimction Tｈｅｎｗｅｗｉｌｌｃｏｍｐａｒｅｗｉｔｈｔｈｅｖａｌｕｅｏｆ targetfUnctionande，ｗｈｅｒｅeisthe accuracyparameterJfFCo,ｙｏ)<e,then

thecalculationisoverandwefindthe

result・IfFCKo,ｙｏ)>e,ｗｅｗｉｌｌｇｏｔｏｎｅｘｔ

ｓｔｅｐ

Ｔｈｅｋ+１(k=0,1,2,…,、)stepcanbc yieldedbyfO11owingequatio､：

|小犀Ｍ+塚ｃｗ何 ^{Ｆ(x脾)ﾉﾙ）．}

|量鰍１１+に’

Fig4Photosofprototypedevice 4.Inputhandwritingchamcters

WCexploitaregulatedDCpower

supplyNipponStabilizerhdustry③

MSA18-5todoexpcriments・ＷＣｄｉｄｅｘｐｅｒｉｍｅｎｔｓｔｏｇｅｔｔｈｅｖａｌｕｅｏf coefficientK・Finallywefinditsvalueas

OOOO31、

Afterthatwetrytogetthehandwriting inputcharacteLAndtheresultiｓｓｈｏｗｎｉｎＦｉｇ５．

ＨｅｒｅＦｘ，Fyarethepartialdifferential oftargetfUnctionF(x,y).pisaparameter ofsteepcstmethod,whichcancontrolthe specdofconvergence、Thecalculation

shouldbecontinueduntilthetarget

－５７－

(5)

withthemagneticsensors、Maybcitwill rotatcaroundy，zaxis，ｏｒｏｆｆＳｅｔａｎｄｍｃｌｉｎｅｆｒｏｍｔｈｅｐｌａｎｅｏfmagnetic sensors・Properlyitalsomayrotatc aroundxaxis，butitwillnotbringany

errorsbccauseofthecharacteristicof

lnagneticficldgencratedbythema印et・

WeinvestigatedthesefOurkindsof misalignmentofmagnetbysimulations andexperiments、FinallywefOundthat rotationaroundzaxiswillbringgreat errortoinputtingresult・Whenthe misalignmentanglewhichisaroundz axisincreases，thcerrorbecomesmucll bigg則proportionatewiththedistancc betweenmagnetandmagneticscnsoLIt willconfUseusmuclliftllemisalignment angleistoobig・Sorotationofmagnet aroundzaxisshouldbeavoidedduring usage・Ｔｈｅexampleofmisalignmentis showninFig.7．

Ⅱ咄】IIII

Fig.５hputtedhmdwritingcharacter

Wedidexperimenttoinvestigatethe positionaccuracyofourdevice・Hcre magnetissetto30pomtsintherectangle withthecomcrof(-004,0.05)and(0.04, 0.15)[m]mlenwetrytogctitsposition byourdevice，Realpositionsand expcrimentalreｓｕｌｔｓａｒｅｓｈｏｗｎｍＦｉｇ６・

Whengeomagnetismcancellationworks，

themaximumerrorofpositionofmagｎｅｔｉｓａｂｏｕｔｌＯｎｎａｔｔｈｃｕｐｐｅｒｃｏｍｃｒｏfthe rectangle，whichisevidentlysmaller61t willnotconfilseusinhandwritinginput

atall．

０．１８

Ｙ；傭

0．１５

0.14

0．１２

Fig7Comparisonofnonnalmputand

Inisalignmentinput

0.1

0.08

⑪､Ｎｏｉｓｅｉｎｃｉｒｃｕｉｔ

ｌｎｏｒｄｅｒｔｏｍａｋｅｏｕｒdevicecompact，

wehavetodecreasethedistancebetween

twomagneticsensors・HoweveLasthe positionofmagnetiscalculatedbythe differenceofoutputsofsensors,wehavc tokeepthisdifferencebiggerthannoise inourcircuit，TherefOre，wedid experimentstoknowthcrangeofnoisein thecircuit,anditisshowninnblel．

0.06

0.04

-0.08-0.06－０．０４-0.02００．０２０．０４０．０６０．０８ CRealpositionpExperi8T吃ntnithgeomagnetismcamcellaticn ＸⅢ

Fig6Experimentalresult

S・Misalignmentofmaどnet

Asthemagnetismountedonuser，s fingerinourdcvice，duringusageitis difficulttokeeptheparallelrelationship

－５８－

ロ

● ロ

◆ ロ

● ロ

◆ ロ

◆

◆ ロ

◆ ◆

。

◆ ロ

◆

□

◆

■

◆ ◆ ◆

□

◆

［◆ ◆

□

◆

。

◆

◆ ◆ ◆

ロ ◆

ロ ^◆

● ロ

◆ ８ロ◆ロ◆

(6)

rtlble1Rangeofnoises 7.Conclusion

hthisrescarchwesuccecdtomakea

prototypehandwritinginputdeviceusmg magneticfield・SD-methodisprovedto beusefilltocalculatethepositionof magnet,Wesuccecdtoinputhandwriting cllaractcrsbyourdevice・Misalignment andnoiseindeviceareinvestigatedd

0.006274 lＵＯ８９８４ -0.005664 ).(川)IＩ

DmingusagethefUrthestpointinthe palmissupposedtobe(-0.06,0.13)ｏｒ (0.06,0.13）［､]・FromEqs.(3)-(4)we

concludethattheminimumtheoretical distancebetweentwosensorsｓｌｌｏｕｌｄｂｅｌ８Ｓｍｍ

学位論文審査結果の要旨

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－５９－

Range(+/-） ^{Ｘａｘｉｓ} ^{Ｙａｘｉｓ} +(v） ^0.006274 ^0.008984

■■

Wearable handwriting input device using magnetic field

Wearable handwriting input device using magnetic field

著者 Han Xinying

著者別名 韓, 新瑩

journal or

publication title

博士学位論文要旨 論文内容の要旨および論文審査 結果の要旨／金沢大学大学院自然科学研究科

volume 平成21年6月

page range 55‑59

year 2009‑06‑01

URL http://hdl.handle.net/2297/26909

氏名 学位の種類 学位記番号 学位授与の日付 学位授与の要件 学位授与の題目

韓新榮 博士（工学）

博甲第１０５４号 平成２０年９月２６日

課程博士(学位規則第４条第１項）

ＷＥＡＲＡＢＬＥＨＡＮＤＷＲＩＴＩＮＧＩＮＰＵＴＤＥⅥＣＥＵＳＩＮＧＭＡＧＮＥＴＩ ＦＩＥＬＤ（磁気を利用したウエアラブル手書き文字入力デバイス）

関啓明（理工研究域・准教授）

神谷好承（理工研究域・教授)，木村春彦（理工研究域・教授)，

立矢宏（理工研究域・教授)，宮崎猛(理工研究域・准教授）

論文審査委員（主査）

論文審査委員（副査）

AZDsZmcr

LIntmduction

Asmfbnnationtecllnologywas developedquicklylmanykindsofinput deviceshavebeendeveloped・Theymake

ourlivesmuchmorecomfOrtableand

ｍｕｃｈｔｉｍｅｔｏｂｅｕｓｅｄｔｏｉｔ・AndfOrelder

person，post-natalvisuallyimpairedand thosewhoarenotskilledinoperationof computeLfCwdevicesarcavailable．

Filrthermore，fewdevicesaredeveloped fOrthewearablecomputing・

TherefOrewehaveproposedanew

devicetofitthedemandabove・Ｉｔｉｓａｂｌｅ

justneedstobefixedontouser,shands・

Ａｎｄｕｓｅｒｃａｎｂｅｕｓｅｄｔｏｉｔｗｉｔｈｏｕｔａｎｙ trainingevenuscrgetitjustnow．

H(昨芸[3r響の－m］ （１）

Ｈｅｒｃｍｉｓｔｈｅｕｍｔｖｅｃｔｏｒｏｆｍａｇｎｅｔｉｃ ｍomentofmagnet,whichshouldbemCK，

y，ｚ)．misthemagneticmomentof magnet・risthelocationvectorofmagnet，

ａｎｄｉｔｓｖａｌｕｅｉｓＬｔｈｅｄｉｓｔｍｃｅｂｅｔｗｅｅn magnetandmagneticsensoL

Whenthemagnetlocatesat(x,ｙＰ)in themagneticsensororientedcoordinate，

mshouldbe(1,0,0),andrshouldbc(_x，

-ｙｐ)．

（Ｈｘ,Ｈ,,Ｈz)＝

（Ｋ・ｚｘ２－ｙ２ ５，３Ｋ. ｊＯノ 5,0）（２）

２．Pmposeddevice

Writil1宵charactersonpalmwith

、

S･Positioningcalculation

BefOrecalculatmgthepositionof magnet，weneedtoknowthemagnetic fieldgeneratedbyit､Magnetlocatesat(x，

y)innlagncticsensororicntedcoordinate willgeneratemagneticfieldwhicllcanbe gottenbyEqs.(1)-(2).Itsinlageisshown inFigZ

（x2＋ｙ２)ｚ （x2＋y2)２

、シ・

ぞ:i>i、

Magnetic

分．

Magnetic

Fig.３Imageofpositioningcalculation

､叱免･口...△へ＿､▲■｡｡｡.～も．､－．－．A.．...□...づぃ..｡.＿ザ①､－－．～..←...．,ﾛﾛﾁﾞｹﾞﾁﾞｹﾞｹﾞゴタナヂグタ

Fig.２Magneticfieldgeneratedbymagnet 血`-Ｍが一二｝

（３）

[jrz+(y＋`/)2]２Cf+ゾ)２ /(（(xj)＝Ｋ･｛

－５６－

fUnctionF(x,y)〈e・

Weselect(0,0.001)astheinitialpoint inSD-methodaｎｄｐｉｓＺ,ｅｉｓｌｅ－３ｉｎｏｕｒ

ｄｅｖｉｃｅ．

刀(xウル3K.｛ｘＯＭ）ｘ)′５｝

（４）

［x2＋(y+c/)2]２（xz＋y2)２

Here，Kisthecoefficientabout magneticmomcntinourdevice.(x,ｙ)is thcpositionofmagnctinmagneticsensor

Aorientedcoordinate・disthedistance betwcentwomagneticsensors・

Becauseitisdifficulttosolve

eqUations(3)-(4)，wcadoptstcepcst descentmethod（SD-method）inour system

lnSD-methodcalculationstartsatan

arbitrarypoint(xo,ｙｏ)．Wetakeaseries ofstepsuntilwearesatisfiedthatweare closeenoughtosolutionWhenwetakea step,wechoosethcdirectionof(f1x,f1y)．

Ａｎｄwcassumethatthetargetfmction

is：

３.Prototypedevice

２－axismagneticsensorHoneywell⑪

HMC-1022isadoptedinourdevice・We

exploithterface②CBI-3133BasA/D

converter、Neodymiumtypemagnet TBuchino⑪51-421isselectedtomount ontouser,sfingertip・Wedcsigneda

mounterfOrit．Ｃ＆DIbchnologies③

ＮＭＡＯ５０５Ｓｉｓｕｓｅｄｉｎｏｕｒｄｅｖｉｃｅａｓ

著者別名韓, 新瑩

博士学位論文要旨論文内容の要旨および論文審査結果の要旨／金沢大学大学院自然科学研究科

氏名学位の種類学位記番号学位授与の日付学位授与の要件学位授与の題目

韓新榮博士（工学）

博甲第１０５４号平成２０年９月２６日

ＷＥＡＲＡＢＬＥＨＡＮＤＷＲＩＴＩＮＧＩＮＰＵＴＤＥⅥＣＥＵＳＩＮＧＭＡＧＮＥＴＩＦＩＥＬＤ（磁気を利用したウエアラブル手書き文字入力デバイス）

H(昨芸[3r響の－m］ ^（１）

Ｈｅｒｃｍｉｓｔｈｅｕｍｔｖｅｃｔｏｒｏｆｍａｇｎｅｔｉｃｍomentofmagnet,whichshouldbemCK，

（Ｋ・ｚｘ２－ｙ２５，３Ｋ. ^ｊＯノ _{5,0）（２）}

（x2＋ｙ２)ｚ（x2＋y2)２

_Magnetic

^（３）

ｐｏｗersupplymodule、ＴｈｅＰＣＢｏｆｏｕｒｄｅｖｉｃｅｉｓｓｈｏｗｎｉｎＦｉｇ４Ａ/Dconverter，

powersupplymoduleandcomputerare notincludedinthephotos・ＴｈｅＰＣＢｉｓｍｏｕｎｔｅｄｏｎｔｈｅｗｒｉｓｔｂｙａｍｏunter6

F(x,)ﾉ)-Z?(x,)')+矛(〃） ⁽⁵⁾

|小犀Ｍ+塚ｃｗ何 ^{Ｆ(x脾)ﾉﾙ）．}

MSA18-5todoexpcriments・ＷＣｄｉｄｅｘｐｅｒｉｍｅｎｔｓｔｏｇｅｔｔｈｅｖａｌｕｅｏf coefficientK・Finallywefinditsvalueas

Afterthatwetrytogetthehandwriting inputcharacteLAndtheresultiｓｓｈｏｗｎｉｎＦｉｇ５．

withthemagneticsensors、Maybcitwill rotatcaroundy，zaxis，ｏｒｏｆｆＳｅｔａｎｄｍｃｌｉｎｅｆｒｏｍｔｈｅｐｌａｎｅｏfmagnetic sensors・Properlyitalsomayrotatc aroundxaxis，butitwillnotbringany

themaximumerrorofpositionofmagｎｅｔｉｓａｂｏｕｔｌＯｎｎａｔｔｈｃｕｐｐｅｒｃｏｍｃｒｏfthe rectangle，whichisevidentlysmaller61t willnotconfilseusinhandwritinginput

concludethattheminimumtheoretical distancebetweentwosensorsｓｌｌｏｕｌｄｂｅｌ８Ｓｍｍ

Range(+/-） ^{Ｘａｘｉｓ} ^{Ｙａｘｉｓ} +(v） ^0.006274 ^0.008984

(v） ^-0.010815 ^-0.005664