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Welcome to the fischertechnik World of ROBOTICS 4

Some General Information 5

Electricity 5

AboutthisActivityBooklet 5

Robot,ArtificialHumans? 6

ROBOTICS,(Almost)EverythingAutomatic 7

Component Explanations 8

EncoderMotors 8

XSMotor 9

LEDs 9

LensTipLamp 9

Phototransistor 10

Pushbutton 10

HeatSensor(NTC) 11

CameraModule 11

ROBOTICSTXTController 12

A Few Tips 13

First Steps 14

Starter Models 15

Pedestrianlight 15

Handdryer 16

TemperatureControl 18

Barrier 19

"CameraMan" 20

SwivelingCamera 22

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Mobile Robots - The Next Challenge 23

MobileRobot 23

HindranceDetector 27

HindranceDetectorwithCamera 28

TrailSearcher 30

DetectionRobot 33

SoccerRobotwithMovementControl 35

SoccerRobot 38

Trouble Shooting 43

InterfaceTest 43

CablesandWiring 43

LooseConnection 43

ShortCircuits 44

PowerSupply 44

ErrorsintheProgram 44

CameraFunction 44

LastSourcesforHelp 45

And what else can I do? 46

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Welcome to the fischertechnik World of ROBOTICS

Hello!

Wearehappyyouhavechosenthe"ROBOTICSTXTDiscoverySet"constructionsetfromfisch-ertechnik.Becausewiththisconstructionsetyoucanconductmanyinterestingexperimentsandsolveexcitingtasks.

Readthisdigitalbookletandtrytheexperimentsandtasks,tolearnstep-by-stephowyoucancontrolandprogramsimpleaswellascomplicatedmachinesandrobotsusingtheROBOTICSTXTControllerfromfischertechnik.

Learningisaprocessofbuildingthingsupfromafoundationanditisnotpossibletostartwiththemostdifficultthingsrightaway,eventhoughtheymaybealittlebitmoreinterestingthanthemoresimpletasks.Thisiswhywehavestructuredtheexperimentsandtasksinthisbookletsothatyoulearnsomethingdifferentwitheverynewtaskandcanthenusethisasthebasisforthenexttask.

Sodon'tworry,wewillstartwithsmallthingsandthenworktogethertoprogresstothebigrobots.

WehopeyouhavealotoffunandsuccessnowexperimentingwithyourROBOTICSTXTDiscoverySet.

Yourteamfrom

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Some General Information

Beforewereallygetstartedwiththeconstructionset,youstillneedtoknowafewthings.Eventhoughthecomponentswewillworkwithareveryrobust,ifyoudonothandlethemproperly,theycanbedamagedundercertaincircumstances.

Electricity

Asyoucertainlyknow,alotofthecomponentsintheROBOTICSTXTDiscoverySetuseelectricpower.Andyouknowitisnecessarytobeparticularlycarefulnottomakeanymistakeswhenworkingwithelectricalcomponents.Thatiswhyyoushouldalwaysreadtheassemblyinstructionsverycarefullywhenwiringtheelectricalcomponents.

Neverconnectthepositiveandnegativepolesdirectlytooneanothertopreventashort-circuit.ThiscandamagetheROBOTICSTXTControllerortherechargeablebattery.

Thesubjectsofelectricityandelectronicsarejustasinterestingasrobotics(whichiswhatthisconstructionsetisabout)andthereisaconstructionsetfromfischertechnik,whichdealsspecificallywiththesesubjects.Ifyouareinterestedinthis,youwillalsohavejustasmuchfunwithour"PROFIElectronics"constructionsetaswiththeROBOTICSTXTDiscoverySet.

About this Activity Booklet

ThisPDFactivitybooklethasanumberoffunctions,whicharenotpresentintheprintedbookletandwhichmayalreadybefamiliartoyoufromtheInternet.

▯ Links within the Booklet

Whensomethingismentionedsomewhereinthetext,whichisexplainedinmoredetailatanotherpointinthisbooklet(forexample,components),thetextappearsindarkblueandunderlined.Youcanclickonthetexttomoveautomaticallytothepagecontainingtheexplanation.Thisiscalleda"crossreference."

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▯ Background Infos

Insomecasesinthisbooklet,therearetermsorforeignwords,whichmayrequireexplanation.Thesetermsaredisplayedingreenandunderlined.Ifyoutouchthetextwiththemousepointer,awindowappearswithanexplanation.

▯ Link Outside of this Booklet

AfewlinksrequireanInternetconnection(forexample,thefischertechnikwebsite),oraninstalledROBOPro(forconnectiontotheROBOProonlinehelp).Thesetermsaredisplayedinlightblueandunderlined.

▯ Pictures

Apictureiswortha1000words.Youhavecertainlyheardthissentencebefore.Andbecausethiscertainlycontainsalotoftruth,youcandisplayapicturebytouchingthewordsinbrownandunderlinedtoseeapictureshowingwhatismeantinthetext.

▯ The ROBO Pro Icon

Thisisalwayslocatedinthevicinityoftasks.Thismakessense,becauseassoonasyouclickonit,asuitableexampleprogramopenswithapossiblesolution.

Allexampleprogramsarelistedunder C:\Programs (x86)\ROBOPro\Example programs\ROBO TX Automation Robots.[Translatorsnote:HavethesedirectorynamesbeenprogrammedinEnglish?Ifnot,theywillhavetoremaininGerman.]

Robot, Artificial Humans?

Whatisyourfirstthoughtwhenyouheartheword"robot?"Haveyoueverseenarobot?Inamovieorontelevision?Orperhapsarealone?

Therearemanydifferenttypesofrobots.Somerobotslookabitlikeahuman,whileothershaveonlyoneormorearms.So,whatexactlymakesarobotarobot?

Thedictionarystates:"Robotsarestationaryormobilemachines,whichperformsettasksaccordingtoacertainprogram."

click-me.rpp

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ROBOTICS, (Almost) Everything Automatic

Thus,robotsaremachinescontrolledbyaprogram.Andwecallthiscontrolofmachines(orinourcasemodels)"ROBOTICS."

The"ROBOTICSTXTDiscoverySet"providesyouwithawonderfulstarttolearnaboutthissubject.Thisisbecausetheconstructionsetcontainseverythingyouneedtobuildandcontrolmanydifferentmachines.

YoucancreatetheprogramsforcontrolofthemodelsonaPCwiththeaidoftheROBOPro4.0(orhigher)softwareandthentransferthemtotheROBOTICSTXTControllerusingtheUSBorBluetoothconnection.Thecontrollerthencontrolsoroperatesthemodelaccordingtotheprogramyouhaveprepared.

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Component Explanations

The construction set contains all of the followingFirst,itcontainsnumerousfischertechnikbuildingblocks,aswellasmotors,indicatorlightsandsensorsandcoloredassemblyinstructionsforbuildingvariousmodels.

Afteryouhaveunpackedallthebuildingblocks,itisnecessarytofirstassembleafewcomponentssuchascablesandplugsbeforeyoucanreallygetstarted.Detailsaregivenintheassemblyinstructionsunder"AssemblyTips."Itisbesttodothisfirst.

ActuatorsActuatorsareallcomponents,whichcanperformsometypeofaction.Thismeansthattheybecome"active"insomewaywhentheyareconnectedtoelectricpower.Inmostcasesyoucanseethisdirectly.Amotorruns,anindicatorlightilluminatesandsoforth.

Encoder Motors

Weusethetwoencodermotors,containedintheconstructionset,todriveourrobots.Atfirstglance,thesearenormalelectricmotors,designedforavoltageof9voltsandmaximumcurrentinputof0.5amperes.

Buttheencodermotorscandomore:Inadditiontotheconnectionforthepowersupplyforthemotor,theyhaveanotherconnectorforathree-pinconnectioncable,whichisusedincombinationwithaso-calledencodertomeasuretherotationofthemotor.

Thisencoderworksthesamewayasaspeedometeronabicycle.Amagnet(inmostcasesforabicyclelocatedononeofthespokes)passesbyasensor(attachedtotheforkofthebicycleinmostcases)witheachrevolutioncausingthesensortogenerateapulse.Thesepulsescanbecounted,and,inthecaseofaspeedometer,forexample,multipliedbythecircumferenceofthetire.Thisgivesusthedistancetraveled.

Theencodersonthefischertechnikencodermotorsgeneratethreepulseseachtimethemotorshaftrevolvesonce.Andbecausetheencodermotorsalsohaveagearboxwithatransmissionratioof21:1

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(read"21to1"),onerevolutionoftheshaftcomingoutofthegearbox,correspondsto21x3=63encoderpulses.

XS Motor

TheXSmotorisanelectricmotor,exactlyaslongandhighasafischertechnikbuildingblock.Inaddition,itisverylight.Thismeans,youcaninstallitatpointstoosmallforthebigmotors.

BothgearboxesincludedintheconstructionsetfitperfectlyontheXSmotor.

TheXSmotorisdesignedforasupplyvoltageof9voltsandamaximumcurrentof0.3amperes.

LEDs

TwoLEDsarecontainedintheconstructionset.Theycanbeusedinavarietyofways.Forexampleassignallightsinatrafficlight,asflashinglightsonarobotorforbetterilluminationofanimagesuppliedbythecameraalsoprovidedintheconstructionset.

TheLEDsaredesignedforavoltageof9voltsandconsumeapproximately0.01amperesofcurrent.

Caution! When connecting LEDs to the power supply, always pay particular attention to correct polarity. Connect the positive pole to the red marking on the LED.

Lens Tip Lamp

Thisincandescentbulbcontainsalenstofocusthelight.ItlooksverysimilartoanLED.Becarefulnottomixthemup.Onthelenstiplampthepolaritymakesnodifference-thisiswhythesocketisnotmarked.Youneedthelenstiplamptobuildalightbarrierincombinationwiththephototransistor.

Thelenstiplampisdesignedforavoltageof9voltsandcurrentofapprox.0.15amperes.

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SensorsSensorsaresotospeakthecounterparttotheactuators.Thisisbecausetheydonotperformanyactions,butreacttocertainsituationsandevents.Forexample,apushbuttonreactswhenpressed,allowinganelectriccurrenttofloworinterruptingitsflow.Aheatsensorreactstothetemperatureinitssurroundings.

Phototransistor

Phototransistorsarealsocalled"lightsensors“.Thisisa"feeler"thatreactstobrightness.

Foralightbarrierthisisthecounterparttothelenstiplamp.Whenthereisahighdegreeofbrightness,thatiswhenthetransistorreceiveslightfromthelenstiplamp,itconductselectricity.Ifthebeamoflightisinterrupted,itdoesnotconductanyelectricity.

Caution! When connecting the phototransistor to the power supply, pay particular attention to correct polarity. Connect the positive pole to the red marking on the phototransistor.

Pushbutton

Thepushbuttoncouldalsobecalledatouchsensor.Pressingtheredbuttonactuatesaswitchmechanicallyallowingelectricitytoflowfromcontact1(middlecontact)tocontact3.Atthesametimethecircuitbetweencontacts1and2isinterrupted.Soyoucanusethepushbuttonintwodifferentways:

As a "normally open switch" (NO or push-to-make switch)

Contacts1and3areconnected.

Pushbuttonswitchpressed:Electricityflows.Whenthepushbuttonisnotpressed:Electricitydoesnotflow

As a "normally closed switch" (NC or push-to-break switch)

Contacts1and2areconnected.

Pushbuttonswitchpressed:Noelectricityflows.Whenthepushbuttonisnotpressed:Electricityflows.

3

1

2

3

1

2

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Heat Sensor (NTC)

Thiscomponentisaheatsensorformeasuringtemperatures.At20°Citselectricalresistanceis1.5kΩ(kiloohms,butpronounced'kil-ohms').NTCstandsforNegativeTemperatureCoefficient.Thissimplymeansthattheresistancevaluedecreaseswhenthetemperatureincreases.

Theinformationprovidedbythesensors,forexample,bright/dark,pressed/notpressedandtemperaturevalue,can,aswewillseelater,betransmittedbytheROBOTICSTXTControllertoaPCwhereitcanbeusedincombinationwiththesoftwaretoprogramamotortodriveafanwhenalightbarrierisinterrupted.

Camera Module

Thecameramoduleisaparticularlyversatiletypeofsensor.Theimageresolutionis1megapixel(meaningthateachimageconsistsofonemillionimagedots).ConnectthecameratothelargeUSBport(USB1)onyourROBOTICSTXTController.TheimagesfromthecameracanbetransferredtothePCandviewedonthemonitor.Thisallowsyoutoseewhatyourrobotisdoingatanyparticulartime.MoreovertheROBOTICSTXTControllercanprocesstheimagestherebyrecognizingmotion,colorsandtracks,allowingyoutocontrolyourrobotmodelaccordingly.ItisalsopossibletoconnectthecameradirectlytoaUSBinterfaceonyourPCandprocesstheimageswiththeROBOProsoftware.Thispossibilityisalsousedbyafewmodels.

Youcanfocusthecameraimagebyturningthecameralens.

ROBO Pro 4.x SoftwareROBOProisagraphicprogramminginterfaceforcreatingprogramsfortheROBOTICSTXTController.

A"graphicprogramminginterface"allowsyoutocompileprogramsvisuallywiththeaidofgraphicsymbolsinsteadof"writing"themoutby

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handlineforline.Anexampleofsuchaprogramisshownattheleft.

TheprocedureforcreatingsuchaprogramisdescribedindetailintheChapter"FirstSteps".TheROBO Pro HelpfeaturealsoshowshowthisworksinChapters3and4.

ThissoftwarehasalreadybeeninstalledonyourPCtogetherwiththisactivitybooklet.

ROBOTICS TXT Controller

TheROBOTICSTXTControlleristheheartofthisROBOTICSconstructionset.Itcontrolsactuators,andevaluatestheinformationfromthesensors.

ForthispurposetheROBOTICSTXTControllerhasnumerousterminalsforconnectiontothecomponents.TheinstructionmanualfortheROBOTICSTXTControllerdescribeswhichcomponentscanbeconnectedtowhichconnectionsandthefunctionsoftheconnections.

ThecolortouchscreenallowsconvenientoperationofyourROBOTICSTXTController.ThecameracontainedintheconstructionsetcanbeconnectedtotheUSBhostport(USB-1).TheintegratedBluetoothandWLANinterfaceisaparticularlyinterestingspecialfeature.ItallowsyoutocompleteawirelesslinkbetweenyourPCandtheROBOTICSTXTController.

YoucandefinehowthecontrollerinteractswiththeindividualcomponentsandwhattheyaretodoindetailintheprogramyouwritewiththeROBOProsoftware.

Power Supply (not included)Asyouknow,manyofthecomponentsintheROBOTICSTXTDiscoverySetneedelectricitytooperate,sonaturallyyoualsoneedapowersupply.

ThefischertechnikAccuSetisbestsuitedforthis.Itisnotincludedintheconstructionset.

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A Few Tips

Experimenting makes the most fun when the experiments also work. This is why you should follow a few basic rules when building the models.

Work carefullyTake your time and look precisely at the assembly instructions for the model. If you have to look for an error later, this will take much longer.

Check the movement of all partsWhen putting models together continually check to see if parts, which have to move, move easily.

Use Interface TestBefore starting to write a program for a model, you should test all parts connected to the ROBOTICS TXT Controller, using the interface test feature in ROBO Pro. How this works is described in the ROBO Pro help in Chapter 2.4.

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First Steps

Nowthatyouhavemadeallofthepreparationsandreadtheinformation,youcanfinallystartworking.

Thischapterdescribeshowto:

▯ buildthefirstsimplemodel,aventilatingfan,andconnectittotheROBOTICSTXTController,

▯ connecttheROBOTICSTXTControllertothepowersupplyandPC,

▯ loadtheROBOProSoftwareandtestthemodel,

▯ loadandstartaROBOProprogram,and

▯ createandstartyourfirstsimpleprogramwithROBOPro

Clickhere,toseethefirst,easy-to-understandsteps.

SinceyouwillbeworkingparticularlywiththeROBOProSoftwareinadditiontothefischertechnik

componentsthemselves,youshouldbefamiliarwiththedetailsforwritingprograms.AndbecausethisisexplainedveryclearlyinChapters3and4oftheROBO Pro Help,it

isbestatthispointtocontinuebyworkingthroughthesechapterscarefully.

Thefollowingtipalsoapplieshere:Takeyourtimeandconcentrate;thenyouwillhavethatmuchmorefunwiththemodelslater.

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Starter Models

AfterreadingthroughChapters3and4intheROBO Pro Help,youwillbeabletoprogramsomeofthemodelsintheconstructionset.Let'sgetstarted.ROBOProhasvariouslevels,whichyoucanselectonthemenubar.WewillstartwithverysimpleprogramsatLevel1.Wheneveryouhavefinishedbuildingandwiringamodel,checkwhetherallinputsandoutputsontheROBOTICSTXTControllerareproperlyconnectedandifthesensors,motorsandlightsallfunctionproperlywiththeaidoftheinterface test.

Pedestrian light

Apedestrianlighthasbeeninstalledinfrontofyourhouse.Sincethetechnicianfromthetrafficlightcompanydoesn'thavemuchtime,youoffertoprogramthetrafficlightcontrolforhim.

Themanexplainstoyouhowthecontrolissupposedtowork.Butfirst,buildthemodel.

Task: (Level1)

Thetrafficlightshouldberedinitially.WhenpushbuttonI1ispressedbyapedestrianthetrafficlightshouldchangetoyellowthreesecondslaterandafteranadditionalfoursecondstored.Thegreenphaseistolastfor10seconds,beforethelightturnsredagain.

Programming Tips:

ThevariousLEDsareassociatedwiththefollowingoutputsontheTXTController.

▯ Red–M1

▯ Green–M2

Turntheindicatorlightsonandoffoneafteranothertoobtainthedesiredsequence.

Youcanloadthefinishedprogrambyclickingonthepictureontheright. Pedestrian_light.rpp

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Hand dryer

Inthebathroomatyourschool,newhanddryershavebeeninstallednexttothesinks.Theseareequippedwithlightbarriersforswitchingthefanonandoff.

First,buildthemodelasdescribedintheassemblyinstructions.

Task 1: (Level 1)

Nowitisnecessarytoprogramthehanddryersothatassoonasthelightbarrierisinterruptedthefanswitchesonandthenbackoffagainafter5seconds.

Programming Tips:

IntheprogramsequencefirstswitchonthelightforthelightbarrieratoutputM2.

Thenwaitonesecondtoallowthephototransistortimetoreacttothelight.Thelightbarriershouldthenworkproperly.

Thencheck(interrogate)thephototransistoratInputI1.Ifthevalueis"1"(lightbarriernotinterrupted),theinputshouldbeinterrogatedcontinuouslyinaloop.

Assoonasthevaluechangesto"0"(lightbarrierinterrupted),switchmotorM1onandthenbackoffafter5seconds.

Thenreturntotheloopforinterrogatingthephototransistor.

Starttheprogramwiththestartbuttonandcheckwhetheritworksthewayyouwant.Ifitdoesworkright,you'reonyourwaytobecomingaprofessionalROBOProprogrammer.

Ifitdoesn'twork,trytofindoutwhy.

Theinterface testallowsyoutocheckwhetherallinputsandoutputsworkproperlyandiftheyareconnectedcorrectly.

Whiletheprogramisrunning,youcanfollowtheprogramsequencewiththeredbuildingblocks.Thisallowsyoutoquicklyseewhereanerrorhascreptin.

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Finallyyoucancompareyourprogramwiththefinishedexampleprogram,whichcanbecalledwiththeiconontheright.

Afteryouhavetakenthishurdle,wewanttochangethetaskslightly:

Task 2: (Level 1)

Theschoolprincipalisalwaysinterestedinsavingenergyanddoesn'tlikethehanddryertocontinuerunningafteryourhandsaredry.Heasksyoutorewritetheprogramsothatthefanshutsoffassoonasyoupullbackyourhands.That'snotaproblemforyou,isit?

Programming Tips:

Asinthefirstprogram,itisnecessarytointerrogatethephototransistorI1.Ifthevalueis"0,"switchmotorM1onandifthevalueis"1"switchmotorM1offandsoforth.

Forthistask,thereisalsoacompleteprogramjustincase:

Handdryer_1.rpp

Handdryer_2.rpp

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Temperature Control

Athomewhereyoulive,anewairconditioningsystemhasbeeninstalled.Ofcourse,youimmediatelyaskedtheplumberhowthetemperaturecontrolworks.Hewashappytoexplaintoyouthatatemperaturesensorcontinuallymeasuresthetemperature.Assoonasamaximumvalueisexceeded,theairconditioningisswitchedon.However,ifthetemperatureisbelowtheminimumvalue,theairconditioningisswitchedoffandtheheatingturnedon.Nowyouneedtotrytoprogramacontrolcircuitbasedonthe"temperaturecontrol"model.Butfirst,buildthemodel.

Task: (Level 1)

TheheatingissimulatedbylenstiplampM2.ThefanatoutputM1servesasthe"airconditioningunit".AnNTCthermistoratinputI8isusedtomeasurethetemperature.

Programthemodelsothataboveacertaintemperaturevaluetheheatingisshutoffandthefanisturnedon.Thisistocoolthehouseuntilaminimumvalueisreached.Thenthefanistobeshutoffandtheheatingturnedon.

Programming Tips:

Please note!TheresistanceoftheNTCthermistordecreaseswithincreasingtemperature.Therefore,theuppertemperaturelimitisthesmallestvalueforI8.Thefanshouldswitchonwhenthislimitisreached.ThelowertemperaturelimitisthelargestvalueforI8.Theheatingshouldswitchonwhenthislimitisreached.

YoucanseethevalueofI8atroomtemperatureusingtheinterface test.TurnontheindicatorlightM2andobservehowmuchthevaluedecreases.Nowswitchonthefantofindouthowmuchthevalueincreases.Usethisasabasisforselectingthelimitsforheatingandcooling.

Youcanopenthefinishedprogrambyclickingontheiconontheright.

Temperature_control.rpp

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Barrier

Suchabarrierisfrequentlylocatedattheentranceorexittoaparkinglot.First,buildthemodelasdescribedintheassemblyinstructions.

Ourbarriercouldbeattheexit.

Task: (Level 2)

Whenacarapproachesthebarrier,itinterruptsalightbarrier.Thisshouldopenthebarrier,leaveitopenacertaintime(e.g.5seconds)andthencloseitagain;howeveronlywhenthelightbarrierisnotinterrupted,becauseotherwisethebarriercoulddamageacarlocatedexactlybelowthebar.Thetrafficlightshouldturngreentoshowthecardriverthatthebarrierisopenandredwhenitisclosed.

Programming Tips:

Useasubroutineforthe"opening"and"closing"operationsforthebarrier(seealsoROBO Pro HelpChap.4).

ForthispurposesetROBOProtoLevel2.

Youcanopenthefinishedprogrambyclickingontheiconontheright.

Barrier.rpp

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"Camera Man"

Nowwewanttotakealookattheinterestingsubjectofcamerasandimageprocessingforthefirsttimeinthisactivitybooklet.Forthispurposebuildthe"cameraman"modelasdescribedintheassemblyinstructionsandconnectthecameradirectlytoyourPCwithaUSBcable.Thecamerawillberecognizedandtheassociatedcameradriverinstalledautomatically.

NowstarttheROBOProsoftware.

Task 1:

PlacethecameramaninfrontofyourPCandletROBOProshowyouwhatthecamera"sees".

Programming Tips:

TodothisitisnotevennecessarytowriteaROBOProprogram.SimplyopenanewprograminROBOPro,gotothe"camera"tab,setthecameraconnectionto"PC"thereandclick"Switchoncamera".

Youcanfocustheimagebyturningthelensonthecamera.

Task 2: (Level 3)

Nowyoucanprogramthecameramantoreacttomotion.Assoonassomeonewalksthroughtheimage,aredlightconnectedtooutputM1shouldflashthreetimesontheTXTController.

Programming Tips:

ConnecttheTXTControllertoyourPCusingasecondUSBinterface.

ConnectanLEDwithredcovertooutputM1ontheTXTController.

Switchtolevel3inROBOPro.RefertotheROBO Pro HelpinChap.5toseetheadditionalfunctionsavailablethere.

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Drawarectangleofthedesiredsizeinthecamera"Motion"sensorfieldinROBOPro.

Theinteractivefieldformotionrecognition,whichcanbeopenedbyright-clickingwiththemouseontheinsertedsensorfield,allowsyoutosethowintensethemotionmustbetoactuatethesensorandhowextensivethemotionmustbeinrelationtotheentiresensorfield,forittoreact.Thebestwayistotryitwiththedefaultvaluesfirstandthenlaterchangethesettingstoseethereaction.

CreatearoutineinROBOProforcheckingwhetherthesensorfieldhasrecognizedamotion.Tointerrogatethesensorfield,usethecamerainputelementfromLevel3inROBOProandusealooptocheckwhethermotionispresent.

Interrogationof"MotionC"input (Changecontrast).Isthevalue >0?Ifso,thelightshouldflash.

FurtherinformationonthecamerasensorfieldsisgiveninROBO Pro HelpChap.11.

Youcanopenthefinishedexampleprogramhere.

Camera_man.rpp

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Swiveling Camera

Nextyoucanbuildasurveillancecameraforyourroom.First,buildthemodelasdescribedintheassemblyinstructions.

Task: (Level 3)

Thiscameraisdrivenbyanencodermotortorepeatedlyturnitslightlybeforecheckingifanythingmovesintheroom.Ifso,itshouldtriggeranalarmontheTXTControllerloudspeaker;ifnothingmoves,itshouldcontinuetoturnslightlybeforecheckingagain.

Afterreachingtheendoftheswivelrange,itshouldreturntoitsinitialpositioninsmallincrements.

Programming Tips:

Thecamerashouldfirstmovetoitsinitialposition(untilpushbuttonI1isdepressed).

Thenitshouldrepeatedlymoveacertainnumberofpulsesintheotherdirection.Youcaneasilycheckhowmanypulsesarepracticalperrotationwiththeaidoftheinterface tests.

Usethecamera"Motion"sensorelementtocheckwhetheranythingchangesintheimage.Ifso,triggeranalarmontheTXTControllerloudspeaker,see(ROBO Pro Help).

Repeatthisoperationuntilthecamerareachestheendofitsswivelrange,thenmovebackintheotherdirectiontolimitswitchI1.

Hereisoursolutionforthistask:

ThismodelcanbeoperatedindependentlyofthePCinthedownloadmode.Itistheperfectsurveillancecameratokeeptrespassersoutofyourroom.

Swiveling_camera.rpp

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Mobile Robots - The Next Challenge

Mobile Robot

Withthismodel,wewanttofindouttogetherhowyoucancontrolamovingrobot.Howdoyougetittomove,howdoesthesteeringworkandcanyouperhapsimproveitsprecision?Wewillanswerthesequestionswiththehelpofthetasksinthischapter.

Butfirstofcourse,youhavetoputtherobottogether.Asalways,youwillfindthedescriptionintheassemblyinstructions.

Takeyourtimeputtingittogether.Lookcloselyatthedrawingsintheassemblyinstructionsandthewiringaswell.IfyoudonotconnectthecomponentstotheROBOTICSTXTControllerasdescribedintheassemblyinstructions,therobotmaynotbehavelikeyouexpect.

Afterassembly,checkallcomponentsconnectedtotheROBOTICSTXTControllerwiththeROBOProsoftwareinterface test.Whenthemotorsturncounterclockwise,therobotshouldmoveforwards.

DirectionofmotionDirectionofrotation,

motor1Directionofrotation,

motor2

Forwards Left LeftBackwards Right Right

Left Left RightRight Right LeftStop Stop Stop

Task 1: Simply Straight Ahead

Havetherobotmovestraightaheadfor3seconds(notonatable,dangeroffallingoff!)andthenstraightbackfor3seconds.

Didtherobotreallycomebacktoitsstartingpoint?

Repeattheprogramseveraltimesandobserveiftherobotreal-lymovespreciselystraightaheadandback.

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ProgrammingTips:

Evenifthistaskiseasyforyou,wewouldliketomakeafewsuggestions:

The Steering

Evenifitisfuntowatchtherobotmovestraightahead,itissomewhatmonotonous.That'swhy,itisnowtimetolearntomoveinacurve.Andhowisthatdone?Verysimple:

Task 2: Also moving in a curve

Lettherobotmovestraightaheadagainforthreeseconds(bothmotorsturningatthesamespeed)thenchangethedirectionofrotationoftherightmotor(M1)foronesecondandthenlettherobotmovestraightaheadagainforthreeseconds(meaningbothmotorsatthesamespeedinthesamedirection).

Findouthowlongyouhavetoletthemotorsrunindifferentdirectionstomaketherobotturn90°.

Programming Tips:

Forthis,changethewaitingtimeafterthecommandforchangingthedirectionofthesecondmotor.

Youcanopenthefinishedprogramasusualbyclickingontheiconontheright.

Task 3: Moving through a figure

Nowthatyouknowhowlongitisnecessarytoreversethedirectionofrotationofamotortomaketherobotturntotherightorleft,programtherobotsothatitmovesinarectangle,returningtoitsstartingposition.

Makeamarktocheckiftherobotreallymovespreciselytoitsstartingposition.

Mobile_robot_1.rpp

Mobile_robot_2.rpp

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Programming Tips:

Youcancreateasubroutinefor"turningacorner."Thiskeepsthemainprogramclearer.

Youprobablyalreadyhavethesolutiontothetaskinyourhead.Buthereisanotherrecommendation,justincase:

Always the same, but not exactly?

Youhaveprobablynoticedthattherepetitionaccuracyoftherobotcouldbeimproved.Evenwhenitperformspreciselythesametaskseveraltimes,theresultisnotalwaysthesame.Thisisduetovariousreasons.Oneoftheseisthatbothmotorsdonotrotateatexactlythesamespeed.Forexample,thegearboxforonemotorcanrunwithmorefrictionthantheothermotor.Andbecausebothmotorsareoperatedatthesamevoltage(ninevolts),thismakesonemotorrotateslowerthantheother.Since,inthepast,wehavecontrolledourrobotusingwaitingtimes,perhapsonewheelhasrotatedfartherduringthistimethantheotherone.

Thus,thesolutionwouldbetohavebothmotorsrotateatexactlythesamespeed.Andthisispreciselywhatencodermotorsdo.

Task 4: Using Encoder Motors

Repeatthelasttaskusingtheencodermotorelementsinsteadofthenormalmotoroutputandwaitingtimeelements.HowtousetheseisdescribedintheROBOProhelpinChap.12.6.

Programming Tip:

Withtheencodermotorelementyoucancontrolbothmotorssimultaneouslywithoneprogramelement.Withthedistanceentryfieldyoucanseteachmotortoturnexactlythedistanceitissupposedto.

Mobile_robot_3.rpp

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Youcanopenthesolutionsuggestionsasusualbyclickingontheiconsontheright.

AnadditionalprogramelementisnotrequiredinROBOProtocountthepulsesatthehighspeedcounterinputsC1-C4.ThecounterinputC1isautomaticallyassignedinternallytomotorM1;M2isconnectedtoC2andsoforth.

Note:Ifthemodeldoesnotmovestraightaheadinspiteofusingtheencodermotorelementsthecausecanbethemodelitself.Forexample,ifahubnut,whichtransferstheforcefromtheaxletothewheels,isnottightenoughtheaxleslipsandthemodelmovesinacurveeventhoughthemotorsarerotatingatthesamespeed.Thereforebesurethehubnutsaretightenedwell.

Mobile_robot_1_sync.rpp

Mobile_robot_2_sync.rpp

Mobile_robot_3_sync.rpp

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Hindrance Detector

Yourrobotcannowmovestraightaheadandturn.Anduptonowitdoesthispreciselyasdescribedinyourprogram.

However,arobotshouldactuallybeabletoreactasindependentlyaspossible.Thisiswhywenowwanttohaveitreacttoobstacleswiththeaidabumper.

First,buildthemodelasdescribedintheassemblyinstructions.

Task:

Thehindrancedetectorshouldmovestraightahead.Assoonasithitsanobstaclewithitsleftbumper,itshouldstop,movebackashortdistance,turnslightlytotherightandthencontinuetomovestraightahead.Ifithitsanobstaclewithitsrightbumper,itshouldmovearoundtheobstacletotheleftinthesamemanner.

Programming Tips:

Leftbumper:PushbuttonI6;Rightbumper:PushbuttonI5

Useasubroutineforeachofthevariousactions:forwards/reverse,goaroundtoleft/right.

Ensurethattherobotdoesnotmovethesamenumberofpulseswhenmovingtotherightandtotheleft;otherwiseitcouldgetintoacornerandnotbeabletogetout.Howeverifthenumberofpulsesisdifferent,itwillbeabletoworkitswayoutofacorner.

Youcanfindthefinishedprogramhere:

Hindrance_detector.rpp

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Hindrance Detector with Camera

Nowyoucanequipyourmobilerobotwithacamerasoitcanseewhereitisgoingandallowyoutocontrolitbyremotecontrol.Todothissimplytakethehindrancedetectorandinstallacameraasdescribedintheassemblyinstructions.ThecameracanbeconnectedtotheUSB-1interfaceontheTXTController.

Task 1:

Firsttherobotshouldbehaveinexactlythesamemannerasthehindrancedetectorwithoutcamera.Inadditionitshouldstopandturnaroundwhenyouholdaredcardinfrontofit.

Usethecamera"Color"sensorfieldforcolorrecognitionanddrawitlargeenoughthatitsareacoversthemajorportionofthecameraimage.

Thensettherobotparameterssothatitmovesstraightaheadaslongasaredcardisnotdetectedandnohindranceispresent.Youcanusethehindrancedetectionfromthe"Hindrancedetectorprogram".

Itisbesttouseyourownsubroutineforcheckingthecolor.Checkthecamerainputtodetermineiftheredvalueisgreaterthangreenandblueandifthecolorislighterthanblack.

Usethesmallredcardcutfromthelargecuttingtemplateintheconstructionset.

The"sensorvalues"inthecamerawindowinROBOProshowthecolorvaluefortheredcard.

Againyoucanseeoursolutionhere:

Note:Avoiddirectsunlight.Therobotmayconfusesunlightwiththeredcard.Particularlybrightsunlightwithahighpercentageofred.

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Task 2: Remote control of robot

Note:ThistaskrequiresaWLANconnectionbetweentheTXTControllerandyourPC.TheprocessforcompletingthisconnectionisdescribedintheinstructionmanualfortheTXTController.

Tips:

AftersuccessfullycompletingtheWLANconnection,opentheappropriateprogramwiththeicon.

Changetothecontrolpanelandlookfortheinterfaceforremotecontrolofthemodelthere.

Starttheprogramintheonlinemode.Nowyoucanusethevariousbuttonsontheremotecontroltocontroltherobotandyoucanalsoseewhereitisgoing.Ifyouoverlookanobstacle,itwillbedetectedbythebumperandthemodelwillautomaticallymovebackashortdistance.

Havefunexploringthearea!

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Trail Searcher

Withthismodelthecameraisusedtomaketherobotmovealongaline.Theamazingpartoftrailsearchingwiththecameraisthat,inadditiontorecognizingwhetheratrackispresent,itcanalsodetectitsprecisepositionandoutputitinthecameraimage.Thisallowstherobottoreactandeithermovestraightahead,whenthetrailisexactlyinthemiddleoftheimageorcorrectitsmotiontotheleftorright,whenthetrailisnotinthemiddle.

Theobjectiveisfortherobottofindtheblacklineandmovealongit.

Butonethingatatime.First,itisnecessarybuildthetrailsearchermodel.Naturallytheassemblyinstructionsdescribehowtodothis.

Afteryouhavecompletedthemodel,youshouldcheckitwiththeinterface testtoensurethatallcomponentsareproperlyconnectedtotheROBOTICSTXTControllerandareworkingcorrectly.

Task 1: Recognition of a trail

Programtherobotsothatitfollowsastraightblacktrailwhenplacedonit.Ifitlosesthetrailoritends,therobotshouldstop.Usetheobstaclecoursefromtheconstructionsetforthistask.

Programming Tips:

Usetheobstaclecoursefromtheconstructionsettotesttheblacktrail.

SetthecamerasothatthetrailisinproperfocusintheROBOProcamerawindow.

Usethecamera"Line"sensorfieldfordetectingthetrail.Itconsistsofastraightlineinthecameraimage,locatedacrosstheimagefromlefttorightwithascalefrom-100to+100.0ispreciselyinthemiddle.

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Furtherinformationonthecamera"Line"sensorfieldisgiveninROBO Pro HelpChap.11.

Nowyoucancheckthepositionofthetrailinyourprogram.

▯ Ifitislocatedbetween–10and+10therobotshouldmovestraightahead(M1andM2=left:v=5)

▯ Between–11and–40itshouldcorrectslightlytotheleft(M1left:v=5,M2left:v=2)

▯ Between+11and+40itshouldcorrectslightlytotheright(M1left:v=2,M2left:v=5)

▯ Atvalues<–40itshouldcorrectstronglytotheleft(M1left:v=5,M2right,v=3)

▯ Atvalues>+40itshouldcorrectstronglytotheright(M1right:v=3,M2left,v=5)

▯ Ifitloosesthetrail,itshouldstop.

Youcanfindthefinishedprogramhere:

Yourrobotcannowreact.Howeveritwouldbeevenbetterifyourrobotwouldturnaroundattheendofthetrailinsteadofjuststopping.

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Task 2: Turning around at the end of the trail and following it back

Expandyourprogramtoincludeafunction,sothatwhentherobotgetsoffthetrailitturnsaroundandreturns.

Programming Tips:

Thereareseveralpossibilitiesforcorrectingthedirection.Youcanstoponemotorandlettheotheronecontinuetorunorhaveonemotorrotateoppositethedirectionofmovement.Experimenttodeterminewhichmethodisbetter.

Hereisoursuggestedsolution:

So!Nowyourrobotcanmoveonvisual"rails".Theonlydisadvantageisthatyoufirsthavetosetitontherail.Wewanttochangethis.Therobotshouldsearchforitstrailonitsown.

Task 3: Finding the trail and following it

Writea"search"subroutinetomaketherobotsearchforablacktrailifitdoesnotfindonewhentheprogramstarts.Forthispurpose,therobotistofirstmoveinacircleforonetime.Ifitdoesnotfindatrailwhenitdoesthisitshouldmovestraightaheadforashortdistance.Assoonastherobotdetectsatrail,itshouldfollowit.Ifthisdoesn't,thesearchshouldstartoverfromthebeginning.Afterithasmovedinacircle10timeswithoutfindingatrail,itshouldstopandflashthreetimes.

Programming Tips:

Incaseyouarenotexactlyontherighttrail,hereisoursuggestedsolution:

Trail_searcher_2.rpp

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Detection Robot

Onthismodelwenowwanttocombineanumberofcamerafunctions.Therobotshouldbeabletolookforwardtodetectitssurroundings,howeveritshouldalsobecapableoflookingdownandfollowingthevariouscoloredtrailsontheobstaclecourseincluded.Moreoveritshouldalsocollectthe"temperaturedata"foritssurroundingsusingitsNTCthermistor.

First,buildthemodelasdescribedintheassemblyinstructions.

Task 1: The robot should function as follows:

Firstplaceitontheblacktrail.Itshouldmovealongittoitsend.Thenitshouldturnaroundandmoveintheoppositedirection.Afterreachingtheendoftheblacktrailwherethetrailiswider,itshouldraisethecameraandlookforward.Ifyouthenholdaredorgreencardinfrontofit,itshouldfirstfollowtheblacktrailandthenturnontotheredorgreentrail.Beforemovingoff,itagainmeasurestheambienttemperatureandsendsittotheTXTControllerdisplay.

Youcancutthesmallcoloredcardsoutofthelargecuttingtemplateintheconstructionset

Programming Tips:

ThisprogramisintendedtoshowyoueverythingthatispossiblewithROBOPro.Sinceweknowthatprogrammingisnotallthatsimple,justloadthepreparedprogramandtryitout:

Task 2:

The"Trail"subroutineisresponsibleforcontrollingtheencodermotorwhilefollowingatrail.Compareitwiththesubroutinefromthetrailsearchermodel.Whatdifferencesdoyousee?

Detection_robot.rpp

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Solution:

Thesubroutineforthedetectionrobotisconsiderablymorecomplicatedthanforthetrailsearcher.Itcontainsacontrolfunctionwhichmakesthedegreetowhichthedirectioniscorrecteddependentonthedistancefromthemiddleofthetrail.Incomparison,thetrailsearcherdifferentiatedonlybetweenstraightahead,minorcorrectionandmajorcorrection.Creatingsuchacontrolfunctionrequiresagreatdealofprogrammingexperience(suchasourprofessionalprogrammershave).Butthecontrolresultsarealsosignificantlybetterthanwiththetrailsearchermodel.Inthefutureyoucansimplyusethissubroutineforyourownprograms,andbehappythatitworkssowell.

Task 3:

Ifyouhaveasmartphone(withAndroidoperatingsystem),youcanuseittocontrolthedetectionrobot.YoucandownloadtheappforthisfromtheGooglePlaystore.Itiscalled"TXTCamdroid“.ConnecttheTXTControllertoyoursmartphoneviaWLANtogetstarted.Youcanseewhatthecameraseesonyoursmartphonedisplay.Youcancontrolthemodelwithdifferentkeysandsenditondiscoverytrips.Havefun!

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Soccer Robot with Movement Control

HaveyoueverheardabouttheRoboCup?ThisistheSoccerWorldCupforrobots.Itisheldina

differentcountryeveryyear.Therearevariousleaguesforvarioustypesofrobots.DetailedinformationisavailableontheRoboCuphomepagehttp://www.robocup.org

Twosuggestionsforconstructionofasoccerrobotaregivenintheassemblyinstructions.

Itisjustasagileasourotherrobots,butinadditionithasalightbarrierfordetectingaballandtriggeringa"kickingmechanism."Nowwecanequipandcontroltherobotswiththecamerainanumberofdifferentways.

First,buildthesoccerrobotwithmovementcontrolasdescribedintheassemblyinstructions.

Thenyoucanprogramitand"train"ittoperformafewballtricks.And,asalwaysyoushouldusetheinterface testtoseeifthemodelfunctionsproperlybeforestartingtheprogramming.

Usetheorangetabletennisballincludedintheconstructionsetfortheball.

Note:Itmaybenecessarytoadjustthepushbutton,usedasalimitswitchfortheleverontheactuatingmechanism,sothatitisdepressedwhentheleverisforward,howeverdoesnotblocktheleversimultaneously.

Withthisrobotthecameraislocatedonitsownstandnexttothemodel,notinstalledonthemodelitself.ItshouldbepluggeddirectlyintotheUSMportonthePC.

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Task 1: "There, he has the ball and shoots . . ."

Thefirststepistoteachtheelectronicballwizardtoshoottheballassoonasitisdetectedbythelightbarrier.Experimentalittlewiththe"shootingspeed."Ashortpausebetween"detection"and"shooting"maypossiblyleadtoanimprovement.

Programming Tips:

ForthistaskitisfirstnecessarytoconnecttheTXTControltoyourPCusingtheUSBcable.Aswiththehanddryeryoushouldwaitafewsecondsafterthelens tip lampswitchesonbeforecheckingthephototransistoronthelightbarrier.

Beingatrainerisnoteasy.Ifyourrobotplayerdoesnotobeyyou,perhapsyoucangetitsattentionwithourprogramsuggestion.

Butsincearealballwizardshouldbeabletodomorethanjustapenaltyshootout,wewanttoexpandthecapabilitiesofoursoccerrobotabit.

Task 2: Motion control for soccer robot

Nowwewanttoprogramthesoccerrobottoreacttomotionsyoumakeinfrontofthecamera.Whenyouwavewithyourlefthand,itshouldmovetotheleft;ifyouwavewithyourrighthanditshouldturntotheright.Ifyouwavewithbothhandsinthemiddleoftheimage,itshouldmovestraightahead.Whenthelightbarrierdetectstheball,itshouldshoot,naturallyintothegoalifpossible.

Programming Tips:

Note:ForthistaskitisnecessarytoconnecttheTXTControltoyourPCviaWLANorBluetooth.

Eventhoughthistaskmaysoundsomewhatdifficultinitially,youhavealreadyusedmostofthefunctionsforthisprogramwithyourotherrobots.

Soccer_robot_movement_control_1.rpp

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Usethreecamera"Motion"sensorfieldsforcontrolofthemotion.Positiononeoftheseinthemiddleofthecameraimage,oneontheleftandoneontheright.Placethecamerainfrontofyourmonitorwhereyoucaneasilyreachthethreeareasinthecamerawindowwithyourarmswithoutthesensorfieldsreactingunintentionally.Forthispurposeplacethefieldspreferablyintheupperhalfofthecamerasurface.

Thensimplyhaveyourprograminterrogatethethreesensorfieldstodeterminewhichofthefieldshasdetectedmotionandactuatetherobotaccordinglytomovetotheleft,rightorstraightahead.YouhavealreadyprogrammedtheshootingmechanisminTask1.Youcanintegratethisintoyourprogram.

ThenstarttheprogramintheROBOProonlinemode.ThecameraimageistransferredtothePCovertheUSBinterface;therobotcontroliswirelessviaBluetoothorWLAN.

Forthismodelyouonlyneedthegoalfromthesoccerstadiumincludedwiththeconstructionset.Youcouldalsousethe"sideboards"tokeeptheballfromrollingaway.Howevertheyareactuallyrequiredfororientationoftherobotonlyafterbuildingthenextmodel.Andnow,havefun"waving"andshootinggoals.

Onceagainwealsohavearecommendedsolutionforthisprogram.

*seealsoROBO Pro Help,Chap.11.

Soccer_robot_movement_control_2.rpp

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Soccer Robot

Althoughitisveryamusingtocontrolthesoccerrobotbywavingyourarms,arealsoccerrobotshouldbeabletokicktheballintothegoalbyitself.Nowwewanttoteachhimtodothisbyinstallingthecameradirectlyontherobot.

Onceagaintheassemblyinstructionsdescribehowtodothis.

ConnectthecameratotheUSB-1interfaceontheTXTController.

Theentiresoccerstadiumisrequiredforthismodel.Itconsistsoftheunprinted,whiterear,youalreadyusedfortheobstaclecourseforthetrailsearcherandthedetectionrobotaswellasthesideboardsprintedwithblackstripesandthegoal.

Therobotneedsthepurewhitebackgroundtodetecttheorangeballwiththecamera"Ball"sensorfield.

Theblackstripesonthesideboards,whichhaveadifferentappearanceoneachside,allowtherobottodetectwhereitisontheplayingfieldandwherethegoalis.Thestripesontherearwallofthegoalshowtherobotwheretoshoot,whenithastheball.

Task 1:

Aswiththedetectionrobot,thisrobotisnoteasytoprogram.ThereforestartbytryingouttheprogramprovidedbyloadingitontheTXTController.

Hereisoursuggestedsolution:

Tips:

Adjustthelensonthecamerasothatthestripesonthegoalsideboardsinthestadiumarefocusedwhentherobotisattheoppositeendofthestadium.

Soccer_robot.rpp

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Positiontherobotinthestadiumandthenthrowaballontotheplayingfield.Therobotwillsearchfortheball,attempttocatchitandshootitinthedirectionofthegoalassoonasithasturnedtofacethegoal.Withalittlelucktherobotwillshoottheballintothegoal.

Task 2:

TrytounderstandhowtheballdetectionworksbasedonthedescriptionintheROBOProhelp.

Solution:

The"Ball"sensorfielddetectsacoloredballonthewhitebackground.Itoutputsthepositionofthecenterpointoftheballinthesensorfield.SeealsoROBO Pro Help,Chap.11.

Similartothetrailsearcher,0isexactlyinthemiddlebetweenrightandleft.Intheverticaldirectionthevaluegoesfrom0toanautomaticallycalculatedmaximumheight.Therobotselectsitsdirectionofmotiondependingonwheretheballislocated.

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Task 3:

Whichcamerasensorelementdoestheprogramusetoevaluatestripesonthesideboards?

Solution:

The"line"sensorelementisused.Incontrasttothetrailsearcher,threelinesensorsarelocatedfromtoptobottominthecamerawindowtodetectthethreehorizontalstripesonthesideboards.Therobotusestheirwidthtocalculatewhereitispresentlylocatedandwhereitneedstomoveto.

Moreoverthestripesallowittorecognizewhenitistooclosetothesideboardandtostopbeforecollidingwiththesideboard.

Task 4:

Two"Exclusion"sensorfieldsarepresentintheROBOProcamerawindowforthisrobot.Canyouimaginewhatthesearefor?

Solution:Thesesensorfieldssupplementthesensorfieldforballrecognition.Theexclusionareasarenotevaluatedwhenlookingfortheball.Thiscanbehelpful,whenobjectssuchasthephototransistorforthesoccerrobotarelocatedintheimageandcouldbemistakenfortheball.

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How does the robot find its way around the playing field?

Maybeyouhavewonderedhowtherobotfindsitswayaroundtheplayingfieldusingthestripecodesonthesideboards.Asamatteroffact,thisisnotasimpleoperation,butitworksaccordingtothefollowingprinciple.

Infacttherobotiscapableofdeterminingitspositionontheplayingfieldtoanaccuracyofapproximately2 cmandanangleofapprox.5degreesbasedonthesideboards.Forthispurposetherobotmeasurestheheightofthesideboardsatvariouspointsandusesthisheighttocalculatethedistancesandthenfinallytheangleandabsoluteposition.Thisprocessisknownastriangulation.

Thesideboardsalwayshave3blackstripeswith2whitestripesinbetween.Oneoftheblackstripesiswiderthantheotherstripes.Thisallowstherobottorecognizewhichsideboardiswhich.Alltotaledthereare5differentsideboardpatterns,oneforeachsideoftheplayingfieldandoneforthegoal.

Moreovertherobotusesthecountingpulsesfromtheencodermotorstocalculatethepositionandanglebetweentriangulationoperations.

Thisprocessisknownasodometry.Odometryismorepreciseforshorttimesanddistances.Howeverithasthedisadvantagethaterrorsaccumulateinthecourseoftime.Forthisreasonthedataobtainedbyodometryiscorrectedusingthedatafromtriangulation.

Thesoccerrobotprogramhastwosubroutinesforthesecalculations:thetriangulationandodometrysubroutines.Ifyouwouldlike,takeacloserlookatthem.Butdon'tbealarmed!Theylookprettycomplicated;andtheyare.

Ifeverythinglookstootheoreticalforyou,don'tworry.Simplyusetheprogramprovided,beamazedathowitworksandmakeabetwithyourfriends,howmanytimestherobotwillhavetotrybeforemakingagoal.

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Here are a few more tips on the playing field:

Ensurethatalargegapisnotpresentbetweenthefloorandthesideboards.Otherwisethecameracouldthinkthegapisastripeandthecalculationofthepositionwouldbewrong.

Topreventthisitisimportantforyoutofoldtheedgesexactlyandensurethattheplayingfieldisplacedonalevelsurface.Inadditionyoucanalsoplacebooksorotherobjectsalongtheoutsidesofthesideboardstohelpholdthemdown.

Iftheballcontinuouslyrollstowardonecornerorfrequentlystopsagainstoneofthesideboards,youcanleveltheplayingfieldbyplacingflatobjectssuchasnewspapers,schoolnotebooks,cardboard,etc.underthecornerssotheballwillrollbacktothemiddleinsteadofstoppingagainstthesideboard.Thiswillputmoreactionintothegame!

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Trouble Shooting

Ifthingsdon'tworkrightfromtheverystartthereisusuallyasimplereason.But,itisnotalwayseasytofind.That'swhywewanttogiveyousomeinformationhereaboutpossiblesourcesoferrors.

Interface Test

Onceagainhereouradvice:CheckeachindividualcomponentforproperfunctionwiththeaidoftheROBOProinterface tests.

Cables and Wiring

Ifanelectricalcomponentdoesnotworkatall,checkthecableusedtoconnectittotheROBOTICSTXTControlleragain.Forthispurposeusethecabletoconnectthelenstiplamptothebattery.Ifthebulblightsupthecableshouldbeokay.

Anothersourceoferrorsareincorrectlyinstalledplugs(forexample,agreenplugonaredcable).

Alsocheckthat"+"and"-"arecorrectlyconnected.Forthispurpose,compareyourmodelwiththeillustrationsintheassemblyinstructions.

Loose Connection

Acomponent,whichworkssometimesanddoesn'tworkatothertimes,probablyhasalooseconnectionsomewhereinthewiringforthecomponent.

The most frequent causes for this are:

▯ LoosePlugs

Whentheplugsforthecablesaretooloose,thatiswobblyinthejacksockets,theydonotprovidesufficientcontact.Inthiscaseyoucancarefullybendthecontactspringsapartatthefrontontheaffectedconnectorsusingascrewdriver.Justalittle,sotheplugsareheldfirmlyinthejacksocketswhenyouplugthemin.

▯ PoorContactbetweenCableandPlug

Alsocheckthecontactbetweenthestrippedendsofthecableintheconnectorandtheconnectoritself.Itmaybesufficienttotightenthescrewsintheconnectorslightly.

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Short Circuits

Whenapositiveandnegativeconnectiontouchoneanotheryouhaveashortcircuit.ThebatteryaswellastheROBOTICSTXTControllerhaveabuilt-infusetokeepthemfrombeingdamagedbyashortcircuit.Theysimplyswitchoffthepowersupplyforawhile.Naturally,yourmodelwillnotworkanymoreeither.

Thecauseforashortcircuitcanbeeitheramistakeinthewiringorscrewswhichhavenotbeentightenedsufficientlyintheconnectors.Theycantouchwhentheconnectorsarepluggedin,causingashortcircuit.That'swhyyoushouldalwayscompletelyscrewinthescrewsandplugintheplugssothatthescrewscannottoucheachother.

Power Supply

Shortinterruptionsormotors,whichruntooslowly,usuallyindicatealowbattery.Inthiscase,youshouldchargetherechargeablebatterywiththebatterycharger.ThebatteryiscompletelychargedwhentheredLEDonthechargerstopsflashingandilluminatescontinuously.

Errors in the Program

Evenifnoonelikestoadmitit:Everyonemakesmistakes.Andespeciallywithcomplexprograms,anerrorcancreepinquitequickly.

Ifyourmodelstilldoesn'tdowhatyouwantittoafteryouhavecheckedeverythingonthemodelitselfandhaveremediedanyfaults,youshouldalsocheckyourprogram.Gothroughitlineforlinetoseeifyoucanfindtheerror.

Youcanalsowatchtheprogramrunningonthemonitorintheonlinemode,whichmeanswiththeROBOTICSTXTControllerconnectedtothePC.Theprogramelementactiveatanygivenmomentishighlightedallowingyoutoalwaysseethepointwheretheprogramisandwheretheerroroccurs.

Camera Function

Thecameraworksbestwhenthelightisgood.

Light too low:Itcannotrecognizecolorormotioninthedark.

Remedy:LEDstoilluminatethecamerafieldofvision.

Light too bright:Excessivelight-directsunlightforexample-changesthecolorvalueandcontrastsothatthelinedetectorcannolongerrecognizethelinessatisfactorily.

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Remedy:Avoiddirectsunlightorreducethelightbypullingthedrapesorclosingtheshutters.

Other remedies:Usethesoftwaretoadaptthecameraproperties.ThiscanbeaccomplishedwiththeROBOProsoftwareinthepropertyfieldsforthecamerasensors.Hereitispossible,forexample,tosetthesensitivityforrecognitionofanobjectandadaptittothesurroundings.DetailsaregiveninROBOProHelpChapter11.

Last Sources for Help

If,inspiteofallthis,youhavenotfoundtheerror,therearestilltwopossibilitiesforobtaininghelp:

▯ EmailHelp

Sendanemailtofischertechnikdescribingtheproblem.

Ouremailaddressis:info@fischertechnik.de.

▯ InternetHelp

YoucanalsovisitourwebsiteontheInternetathttp://www.fischertechnik.de.Thesiteincludesaforumwhereyouarecertaintofindhelp.Inaddition,youcanalsobecomeamemberofthefischertechnikFanClubatnocharge.

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And what else can I do?

Wasthateverything?No,ofcoursenot.Theexperimentsandmodelsyoutriedoutinthisbookletshouldonlybethebeginning.Your"firstattemptstowalk"sotospeakinthegiganticandexcitingrealmof"ROTBOTICS".

WhatwehaveshownyouhereisonlyaverysmallportionofthepossibilitiesofferedbyyourROBOTICSTXTControllerandthefischertechnikcomponents.Andnowitisyourturn.Youcangiveyourfantasyfreereinandsimplybuildwhatyoufeellike.

Ifyoudon'thaveanyideasforyourowncompletemodelthenjusttakealookatthemodelsinthisbooklet.Perhapssomethingwilloccurtoyouhowtobuildamodeldifferently.Oryoucanchangethefunctionofamodel.

Forexampleyoucouldfastenapentothemobilerobot,sothatitcanbemovedupanddownallowingittowriteonalargepieceofpaperwhiletherobotismovingacrossit.Thenyoucandrawthefigurestherobotmovesthrough.Thisturnsyourmobilerobotintoadrawingmachine.

Youcanalsouseathickfelt-tippentodrawyourownobstaclecourseonapieceofpaperandhavetherobotmovethroughit.AndifyourfriendshaveaROBOTICSTXTController,youcandoevenmoreinterestingthings.Youcanrunracestoseewhoserobotcanmasteragivenobstaclecoursefaster.And,inadditiontoallowingyourPCtocommunicatewiththeROBOTICSTXTController,theBluetoothinterfacecanalsobeusedtoconnectanumberofcomputerswithoneanother.Then,forexample,youcouldprogramtworobots,toreacttooneanother.Ordancewitheachother.AgreatdealofinterestinginformationonthissubjectisgiveninChapters4.5and7intheROBO Pro Help.

Not finished yet

Fantasy

Changing the present

Drawing machine

Racing with friends

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DoesyourcomputerhaveaWLANinterface?IfsoyoucanconnecttheROBOTICSTXTControllertothecomputerusingWLANinsteadofaUSBcable.Ifnot,youcanbuyaUSBWLANstickanduseitforwirelessconnectionbetweenyourROBOTICSTXTControllerandPC.ThisisdescribedintheinstructionmanualfortheROBOTICSTXTControllersandathttp://www.fischertechnik.de.

So,whatareyouwaitingfor?Getstarted!Inventandexperiment!Anddon'tbebotheredbylittlesetbacks.Patienceandperseveranceareprimaryfactorsforexperimenting.Therewardafterthisisafunctioningmodel.

Wehopeyouhavelotsoffuntryingoutyourownideas.

Wireless freedom

Persistence pays off