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机械工程系2010年推免硕士研究生面试综合测试试题编号姓名评分一、将下面的英文段落翻译成中文1.ThedevelopmentofCAMsystemscanbecharacterizedbycreatingmoreandmoreintegratedproducts,moreandmorecostlyandinconvenientinexploitation.Suchsystemcontainsalotoffunctionsofferedtousers,whicharerarelyusedindailyactivity.2.Programmableautomatedproductionsystemsareusedinlow-andmedium-volumeproduction.Thepartsorproductsaretypicallymadeinbatches.Toproduceeachnewbatchofadifferentproduct,thesystemmustbereprogrammedwiththesetofmachineinstructionsthatcorrespondtothenewproduct.Thephysicalsetupofthemachinemustalsobechanged:Toolsmustbeloaded,fixturesmustbeattachedtothemachinetable,andtherequiredmachinesettingsmustbeentered.Thischangeoverproceduretakestime.Consequently,thetypicalcycleforagivenproductincludesaperiodduringwhichthesetupandreprogrammingtakesplace,followedbyaperiodinwhichthebatchisproduced.Examplesorprogrammableautomationincludenumericallycontrolled(NC)machinetools,industrialrobots,andprogrammablelogiccontrollers.3.Amachineformedbyamechanismincludingseveraldegreesoffreedom,oftenhavingtheappearanceofoneorseveralarmsendinginawristcapableofholdingatooloraworkpieceoraninspectiondevice.Inparticular,itscontrolunitmustuseamemorizingdeviceandsometimesitcanusesensingoradaptationappliancestakingintoaccountenvironmentandcircumstances.Thesemultipurposemachinesaregenerallydesignedtocarryoutarepetitivefunctionandbeadaptedtootherfunctions.二、简要回答以下问题1)齿轮传动轮齿主要的失效形式有哪几种？2)螺纹联接的主要类型有哪几种？3)切削加工中精基准的选择原则包括哪些？4)零件在车床三爪卡盘上定位加工外圆表面时，限制了哪几个自由度？5)PLC的基本组成有哪几部分？PLC的扫描循环包含哪几个步骤？6)步进电机在大负载和高速下容易出现什么问题，在低速下容易出现什么问题？7)单片机的局部总线有哪几种？三、这些零件的结构均存在问题，请修改在图中，并简要说明理由。33.54