毕业设计（论文）单片机温度控制英文文献

毕业设计（论文）单片机温度控制英文文献TEMPERATURECONTROLUSINGAMICROCONTROLLERANINTERDISCIPLINARYUNDERGRADUATEENGINEERINGDESIGNPROJECTJAMESSMCDONALDDEPARTMENTOFENGINEERINGSCIENCETRINITYUNIVERSITYSANANTONIOTX78212ABSTRACTTHISPAPERDESCRIBESANINTERDISCIPLINARYDESIGNPROJECTWHICHWASDONEUNDERTHEAUTHORSSUPERVISIONBYAGROUPOFFOURSENIORSTUDENTSINTHEDEPARTMENTOFENGINEERINGSCIENCEATTRINITYUNIVERSITYTHEOBJECTIVEOFTHEPROJECTWASTODEVELOPATEMPERATURECONTROLSYSTEMFORANAIRFILLEDCHAMBERTHESYSTEMWASTOALLOWENTRYOFADESIREDCHAMBERTEMPERATUREINAPRESCRIBEDRANGEANDTOEXHIBITOVERSHOOTANDSTEADYSTATETEMPERATUREERROROFLESSTHAN1DEGREEKELVININTHEACTUALCHAMBERTEMPERATURESTEPRESPONSETHEDETAILSOFTHEDESIGNDEVELOPEDBYTHISGROUPOFSTUDENTSBASEDONAMOTOROLAMC68HC05FAMILYMICROCONTROLLERAREDESCRIBEDTHEPEDAGOGICALVALUEOFTHEPROBLEMISALSODISCUSSEDTHROUGHADESCRIPTIONOFSOMEOFTHEKEYSTEPSINTHEDESIGNPROCESSITISSHOWNTHATTHESOLUTIONREQUIRESBROADKNOWLEDGEDRAWNFROMSEVERALENGINEERINGDISCIPLINESINCLUDINGELECTRICALMECHANICALANDCONTROLSYSTEMSENGINEERING1INTRODUCTIONTHEDESIGNPROJECTWHICHISTHESUBJECTOFTHISPAPERORIGINATEDFROMAREALWORLDAPPLICATIONAPROTOTYPEOFAMICROSCOPESLIDEDRYERHADBEENDEVELOPEDAROUNDANOMEGATMMODELCN390TEMPERATURECONTROLLERANDTHEOBJECTIVEWASTODEVELOPACUSTOMTEMPERATURECONTROLSYSTEMTOREPLACETHEOMEGASYSTEMTHEMOTIVATIONWASTHATACUSTOMCONTROLLERTARGETEDSPECIFICALLYFORTHEAPPLICATIONSHOULDBEABLETOACHIEVETHESAMEFUNCTIONALITYATAMUCHLOWERCOSTASTHEOMEGASYSTEMISUNNECESSARILYVERSATILEANDEQUIPPEDTOHANDLEAWIDEVARIETYOFAPPLICATIONSTHEMECHANICALLAYOUTOFTHESLIDEDRYERPROTOTYPEISSHOWNINFIGURE1THEMAINELEMENTOFTHEDRYERISALARGEINSULATEDAIRFILLEDCHAMBERINWHICHMICROSCOPESLIDESEACHWITHATISSUESAMPLEENCASEDINPARAFFINCANBESETONCADDIESINORDERTHATTHEPARAFFINMAINTAINSTHEPROPERCONSISTENCYTHETEMPERATUREINTHESLIDECHAMBERMUSTBEMAINTAINEDATADESIREDCONSTANTTEMPERATUREASECONDCHAMBERTHEELECTRONICSENCLOSUREHOUSESARESISTIVEHEATERANDTHETEMPERATURECONTROLLERANDAFANMOUNTEDONTHEENDOFTHEDRYERBLOWSAIRACROSSTHEHEATERCARRYINGHEATINTOTHESLIDECHAMBERTHISDESIGNPROJECTWASCARRIEDOUTDURINGACADEMICYEAR199697BYFOURSTUDENTSUNDERTHEAUTHORSSUPERVISIONASASENIORDESIGNPROJECTINTHEDEPARTMENTOFENGINEERINGSCIENCEATTRINITYUNIVERSITYTHEPURPOSEOFTHISPAPERISTODESCRIBETHEPROBLEMANDTHESTUDENTSSOLUTIONINSOMEDETAILANDTODISCUSSSOMEOFTHEPEDAGOGICALOPPORTUNITIESOFFEREDBYANINTERDISCIPLINARYDESIGNPROJECTOFTHISTYPETHESTUDENTSOWNREPORTWASPRESENTEDATTHE1997NATIONALCONFERENCEONUNDERGRADUATERESEARCH1SECTION2GIVESAMOREDETAILEDSTATEMENTOFTHEPROBLEMINCLUDINGPERFORMANCESPECIFICATIONSANDSECTION3DESCRIBESTHESTUDENTSDESIGNFINALLYSECTION5OFFERSSOMECONCLUSIONS2PROBLEMSTATEMENTTHEBASICIDEAOFTHEPROJECTISTOREPLACETHERELEVANTPARTSOFTHEFUNCTIONALITYOFANOMEGACN390TEMPERATURECONTROLLERUSINGACUSTOMDESIGNEDSYSTEMTHEAPPLICATIONDICTATESTHATTEMPERATURESETTINGSAREUSUALLYKEPTCONSTANTFORLONGPERIODSOFTIMEBUTITSNONETHELESSIMPORTANTTHATSTEPCHANGESBETRACKEDINAREASONABLEMANNERTHUSTHEMAINREQUIREMENTSBOILDOWNTOALLOWINGACHAMBERTEMPERATURESETPOINTTOBEENTEREDDISPLAYINGBOTHSETPOINTANDACTUALTEMPERATURESTRACKINGSTEPCHANGESINSETPOINTTEMPERATUREWITHACCEPTABLERISETIMESTEADYSTATEERRORANDOVERSHOOTALTHOUGHNOTEXPLICITLYAPARTOFTHESPECIFICATIONSINTABLE1ITWASCLEARTHATTHECUSTOMERDESIREDDIGITALDISPLAYSOFSETPOINTANDACTUALTEMPERATURESANDTHATSETPOINTTEMPERATUREENTRYSHOULDBEDIGITALASWELLASOPPOSEDTOSAYTHROUGHAPOTENTIOMETERSETTING3SYSTEMDESIGNTHEREQUIREMENTSFORDIGITALTEMPERATUREDISPLAYSANDSETPOINTENTRYALONEAREENOUGHTODICTATETHATAMICROCONTROLLERBASEDDESIGNISLIKELYTHEMOSTAPPROPRIATEFIGURE2SHOWSABLOCKDIAGRAMOFTHESTUDENTSDESIGNTHEMICROCONTROLLERAMOTOROLAMC68HC705B166805FORSHORTISTHEHEARTOFTHESYSTEMITACCEPTSINPUTSFROMASIMPLEFOURKEYKEYPADWHICHALLOWSPECIFICATIONOFTHESETPOINTTEMPERATUREANDITDISPLAYSBOTHSETPOINTANDMEASUREDCHAMBERTEMPERATURESUSINGTWODIGITSEVENSEGMENTLEDDISPLAYSCONTROLLEDBYADISPLAYDRIVERALLTHESEINPUTSANDOUTPUTSAREACCOMMODATEDBYPARALLELPORTSONTHE6805CHAMBERTEMPERATUREISSENSEDUSINGAPRECALIBRATEDTHERMISTORANDINPUTVIAONEOFTHE6805SANALOGTODIGITALINPUTSFINALLYAPULSEWIDTHMODULATIONPWMOUTPUTONTHE6805ISUSEDTODRIVEARELAYWHICHSWITCHESLINEPOWERTOTHERESISTIVEHEATEROFFANDONFIGURE3SHOWSAMOREDETAILEDSCHEMATICOFTHEELECTRONICSANDTHEIRINTERFACINGTOTHE6805THEKEYPADASTORM3K041103HASFOURKEYSWHICHAREINTERFACEDTOPINSPA0PA3OFPORTACONFIGUREDASINPUTSONEKEYFUNCTIONSASAMODESWITCHTWOMODESARESUPPORTEDSETMODEANDRUNMODEINSETMODETWOOFTHEOTHERKEYSAREUSEDTOSPECIFYTHESETPOINTTEMPERATUREONEINCREMENTSITANDONEDECREMENTSTHEFOURTHKEYISUNUSEDATPRESENTTHELEDDISPLAYSAREDRIVENBYAHARRISSEMICONDUCTORICM7212DISPLAYDRIVERINTERFACEDTOPINSPB0PB6OFPORTBCONFIGUREDASOUTPUTSTHETEMPERATURESENSINGTHERMISTORDRIVESTHROUGHAVOLTAGEDIVIDERPINAN0ONEOFEIGHTANALOGINPUTSFINALLYPINPLMAONEOFTWOPWMOUTPUTSDRIVESTHEHEATERRELAYSOFTWAREONTHE6805IMPLEMENTSTHETEMPERATURECONTROLALGORITHMMAINTAINSTHETEMPERATUREDISPLAYSANDALTERSTHESETPOINTINRESPONSETOKEYPADINPUTSBECAUSEITISNOTCOMPLETEATTHISWRITINGSOFTWAREWILLNOTBEDISCUSSEDINDETAILINTHISPAPERTHECONTROLALGORITHMINPARTICULARHASNOTBEENDETERMINEDBUTITISLIKELYTOBEASIMPLEPROPORTIONALCONTROLLERANDCERTAINLYNOTMORECOMPLEXTHANAPIDSOMECONTROLDES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SSEDRESOLUTIONOFTHESEISSUESGENERALLYREQUIRESKNOWLEDGEBEYONDTHATACQUIREDININTRODUCTORYCOURSESBUTREALISTICALLYACCESSIBLETOADVANCEUNDERGRADUATESTUDENTSESPECIALLYWITHTHEADVICEANDSUPERVISIONOFFACULTYDESIRABLEFEATURESOFTHEPROBLEMFROMAPEDAGOGICALVIEWPOINTINCLUDETHEUSEOFAMICROCONTROLLERWITHSIMPLEPERIPHERALSTHEOPPORTUNITYTOUSEFULLYAPPLYINTRODUCTORYLEVELMODELINGOFPHYSICALSYSTEMSANDDESIGNOFCLOSEDLOOPCONTROLSANDTHENEEDFORRELATIVELYSIMPLEEXPERIMENTATIONFORMODELVALIDATIONANDSIMULATIONFORDETAILEDPERFORMANCEPREDICTIONALSODESIRABLEARESOMEOFTHETECHNOLOGYRELATEDASPECTSOFTHEPROBLEMINCLUDINGPRACTICALUSEOFRESISTIVEHEATERSANDTEMPERATURESENSORSREQUIRINGKNOWLEDGEOFPWMANDCALIBRATIONTECHNIQUESRESPECTIVELYMICROCONTROLLERSELECTIONANDUSEOFDEVELOPMENTSYSTEMSANDPRINTEDCIRCUITDESIGNREFERENCES1MLANGSDORFMRALLDSCHUCHMANNANDPRINEHARTTEMPERATURECONTROLOFAMICROSCOPESLIDEDRYERIN1997NATIONALCONFERENCEONUNDERGRADUATERESEARCHAUSTINTXAPRIL1997POSTERPRESENTATION2MOTOROLAINCPHOENIXAZTEMPERATUREMEASUREMENTANDDISPLAYUSINGTHEMC68HC05B4ANDTHEMC144891990MOTOROLASEMICONDUCTORAPPLICATIONNOTEAN4313MOTOROLAINCPHOENIXAZHC05MCULEDDRIVETECHNIQUESUSINGTHEMC68HC705J1A1995MOTOROLASEMICONDUCTORAPPLICATIONNOTEAN12384MOTOROLAINCPHOENIXAZHC05MCUKEYPADDECODINGTECHNIQUESUSINGTHEMC68HC705J1A1995MOTOROLASEMICONDUCTORAPPLICATIONNOTEAN12395MOTOROLAINCPHOENIXAZRAPIDINTEGRATEDDEVELOPMENTENVIRONMENTUSERSMANUAL1993RAPIDWASDEVELOPEDBYPEMICROCOMPUTERSYSTEMSINC单片机温度控制JAMESSMCDONALD工程科学系三一大学德克萨斯州圣安东尼奥市78212摘要本文所描述的是作者领导由四个三一大学高年级学生组成的团队进行的一个跨学科工程项目的设计该项目的目标是设计一个气室内温度控制系统该系统的要求是当实际气室的温度阶跃响应时规定范围内的温度进入气室后稳定时的温度误差和超调量必须少于一个绝对温度本组学生开发设计是基于摩托罗拉MC68HC05系列单片机该问题的教学价值也通过某些步骤的关键描述在本文说明研究结果表明解决该方案需要具有广泛的工程学科知识包括相关电子机械和控制系统工程的知识1引言该设计项目来自一个实际应用问题一个关于显微镜载玻片干燥剂温控器欧米茄CN390温度控制器而这个设计的目标是研发一个自定义的通用温度控制系统取代欧米茄系统一个以更低的成本实现相同功能的自定义控制器就像欧米茄系统一样并不需要能够全方位的处理各种问题该载玻片干燥机的机械布局如图1所示干燥机的主体是一个足够大的绝缘充气室里面依次存放着薄纸包着的石蜡为了使石蜡保持适当稳定性载玻片气室的温度必须维持稳定第二个气筒电子围绕元件设有一个电阻加热器一个温度控制器以及一个安装在干燥机上的风扇是为了把风吹过加热器把热量带到载玻片气室图11载玻片干燥机的机械布局自199697学年来本文作者带领四位三一大学工程科学系的高年级学生开展此项目的研究本文的目的说明了提出一些问题并详细阐述学生的一些解决方案而且讨论了这种类型的跨学科设计项目在教学方面应用的问题这份学生报告曾经在1997年全国本科毕业生研讨会上提出过并讨论过第2节给出该设计的更多详细情况包括性能规格第3节具体学生的设计第4节是论文的主体讨论该设计在教学应用方面的实施问题最后第5节全文总结2问题阐述该项目基本的思想是设计一个自定义温度控制系统来取代相关的欧米茄CN390温度控制器温度时通常保持在一个稳定的常数但重要的是阶跃变化可以被合理的跟踪因此主要要求如下可以对空气室的温度进行设定同时显示设定值和实际温以及在设定温度值情况下可接受范围内的跟踪阶跃变化稳态误差超调量设定温度接口范围精度6099C1C设定温度显示范围精度6099C1C室内温度显示范围精度准确度6099C1C1C室内温度阶梯响应范围稳定状态精度稳定状态最大超调设定时间到16099C1C1C120S表1温度控制器的规格说明尽管表1部分说明并不明确但是它清楚的反映了人们对数字显示器在设定值和实际温度的要求和温度应该通过数值输入来设定而不是通过电位器设置3系统设计根据微控设计数字温度显示和单点输入的要求可能是最合适的图2为学生的设计框图图22温度控制器硬件结构图摩托罗拉MC68HC705B16简称6805是系统的核心它通过一个简单的4键小键盘对温度进行设定同时使用两个显示驱动控制7段LED数码管来显示定值和气室温度的测量值所有这些输入和输出信号与6805的并行口相连气室的温度值使用预校准热敏电阻测量并通过6805的数模转换输入最后6085的脉冲宽度调制PWM输出用来驱动一个继电器以控制线性电阻加热器的闭合和断开图3更详细的显示了6805的接口和电子器件使用暴风3K041103型号四键键盘通过PA0PA3端口进行数据输入其中一个重要的功能是进行模式切换两种模式固定模式和运行模式在固定模式下其他两个键用于设定温度一个增加一个减少第四个按键暂无作用LED显示屏由哈里斯半导体ICM7212进行驱动通过PB0PB6端口与芯片相连作为输出热敏电阻由电压分频器驱动通过AN0针脚八个模拟输入端口中的一个相连最后PLMA针脚两个PWM输出端口中的一个驱动加热继电器图23单片机原理图图3单片机原理图是关于用软件实现温度控制算法保持温度显示以及改变键盘输入响应这将不会在本文详细讨论因为这并不是本文的重点也没有编译完成软件部分还没有确定控制算法但很可能是一个简单的比例控制比PID算法简单一些控制设计的问题将在第四节讨论设计过程虽然该项目的本质是建立一个恒温器但它有许多很好的契机可以供教学借鉴高级工程本科教育的知识只是能够让学生们具有解决问题的能力然而很多情况下实际情况却和理论有些不同不过这些不是问题参与这个项目的设计将获得很多设计方面的宝贵经验本节的其余部分着眼于其他的几个方面41节讨论系统的一些特征简化系统热性能的数学模型以及一些简单理论的证明42节介绍确定实际控制算法43节指出控制设计程序的一些不足并通过模拟环境指出怎样克服问题41数学模型集总元件热系统符合线性控制适用于载玻片干燥机的问题图4显示了二阶集总元件热量模型的载玻片干燥机状态变量是温度TA是箱内空气的温度TB是箱子本身的温度该系统输入功率等于QT的热量和环境温度T的和MAMB分别对应空气和箱子的质量CA和CB则分别是其对应热量M1和M2分别是空气与箱子间以及箱子与外界间的传热系数图4集总元件热模型由图4可以推出线性状态方程拉普拉斯变换1和2等式并整理TAS有趣的是可以推出一个开环的热系统方程其中K是一个常数DS是一个二阶的多项式KZ以及系数DS和在1和2等式中出现的系数功