ElectronicpowersteeringsystemWhatitisElectricallypoweredsteeringusesanelectricmotortodriveeitherthepowersteeringHYPERLINK"http://www.indiacar.com/infobank/epc.htm"\t"_top"hydraulicpumporthesteeringlinkagedirectly.Thepowersteeringfunctionisthereforeindependentofenginespeed,resultinginsignificantenergysavings.Howitworks:ConventionalpowerHYPERLINK"http://www.indiacar.com/infobank/epc.htm"\t"_top"steeringsystemsuseanengineaccessorybelttodrivethepump,providingpressurizedfluidthatoperatesapistoninthepowersteeringgearoractuatortoassistthedriver.Inelectro-hydraulicsteering,oneelectricallypoweredsteeringconceptusesahighefficiencypumpdrivenbyanHYPERLINK"http://www.indiacar.com/infobank/epc.htm"\t"_top"electricmotor.Pumpspeedisregulatedbyanelectriccontrollertovarypumppressureandflow,providingsteeringeffortstailoredfordifferentdrivingsituations.Thepumpcanberunatlowspeedorshutofftoprovideenergysavingsduringstraightaheaddriving(whichismostofthetimeinmostworldmarkets).DirectelectricsteeringusesanelectricmotorattachedtotheHYPERLINK"http://www.indiacar.com/infobank/epc.htm"\t"_top"steeringrackviaagearmechanism(nopumporfluid).Avarietyofmotortypesandgeardrivesispossible.Amicroprocessorcontrolssteeringdynamicsanddrivereffort.Inputsincludevehiclespeedandsteering,wheeltorque,angularpositionandturningrate.WorkingInDetail:A"steeringsensor"islocatedontheinputshaftwhereitentersthegearboxhousing.Thesteeringsensorisactuallytwosensorsinone:a"torquesensor"thatconvertssteeringtorqueinputanditsdirectionintovoltagesignals,anda"rotationsensor"thatconvertstherotationspeedanddirectionintovoltagesignals.An"interface"circuitthatsharesthesamehousingconvertsthesignalsfromthetorquesensorandrotationsensorintosignalsthecontrolelectronicscanprocess.Inputsfromthesteeringsensoraredigestedbyamicroprocessorcontrolunitthatalsomonitorsinputfromthevehicle'sHYPERLINK"http://www.indiacar.com/infobank/epc.htm"\t"_top"speedsensor.Thesensorinputsarethencomparedtodeterminehowmu