基于单片机的金属探测器的设计学生：指导教师：内容摘要：本文着重介绍了一种基于AT89S52单片机控制的智能型金属探测器的硬件组成、软件设计、工作原理及主要功能。该金属探测器以AT89S52单片机为核心，采用线性霍尔元件UGN3503作为传感器，来感应金属涡流效应引起的通电线圈磁场的变化，并将磁场变化转化为电压的变化，单片机测得电压值，并与设定的电压基准值相比较后，决定是否探测到金属。系统软件采用汇编语言编写。在软件设计中，采用了数字滤波技术消除干扰，提高了探测器的抗干扰能力，确保了系统的准确性。此外，文中还对影响金属探测器的灵敏度与稳定性的因素进行了探讨，认为仪器的工作频率、检测线圈的尺寸及匝数等是影响灵敏度的主要因素;而应用现场的环境温度、湿度及线圈的制作工艺和供电电源的稳定程度是仪器稳定性的影响因素。关键词：单片机金属探测器线性霍尔元件电磁感应灵敏度Designforvendingmachine'sPLCsystemAbstract:Thispaperdescribesthecompositionofhardwareandsoftware,workingprinciplesandthefunctionsofanintelligentmetaldetectorwhichmainlyconsistsofAT89S52Single-ChipMicrocomputerandlinearHall-EffectSensor.TheequipmentadoptsUGN3503Ulinearhall-effectsensorasprobetodetectthemagneticfieldchangeofthecentreofasearchcoilresultedfromeddycurrenteffectandturnthismagneticfieldchangeintovoltagechange.TheSingle-ChipMicrocomputermeasuresthepeakvalueofvoltageandcomparesitwithreferencevoltage.Thendeterminewhetherdetectmetelornot.Incaseofdetectionofametallicmass,theMetalDetectorporvidesanacousticalandopticalalarm.Thesystemssoftwareadoptstheassmblerlanguagetobewritten.Insidethesoftware,thedigitalfiltertechnologyisutilizedtoeliminatethejamming.Sothestabilityofsystemandmeasuringveracityareimproved.TheeffectofallfactorsonsensitivityandstabilityofMetelDetetorarediscussedinthispaper.Itisconcludedthattheoperatingfrequency,thesizeofthesearchcoilandturnsarethemainfactorseffectedonthesensitivityoftheinstrument:theenvironmenttemperatureandhumidityinsite,thewindingtechnologyofcoilsandthestabilityofpowersupplyarethefactorseffectedonstabilityofinstrument.KEYWORDS:Single-ChipMicrocomputermetaldetectorlinearhall-effectsensorelectric-magneticinductionsensitivity目录TOC\o"1-3"\h\z\uHYPERLINK\l"_Toc288037327"前言…………………………………………………………………………………….1HYPERLINK\l"_Toc288037328"1分析探测金属的理论根据………………………………………………………………...2HYPERLINK\l"_Toc288037329"1.1理论描述………………………………………………………………….…………..2HYPERLINK\l"_Toc288037330"1.1.1线圈介质条件变化............................................