3. HARDWARE DESCRIPTION3.1 DC Motor: DC motors are configured in many types and sizes, including brush less, servo, and gearmotor types. A motorconsists of a rotor and a permanent magnetic field stator. The magneticfield is maintained using either permanent magnets or electromagnetic windings. DC motors aremost commonly used in variable speed and torque.Motion and controls cover a wide range of components that in some way are used togenerate andor control motion. Areas withinthis categoryinclude bearings andbushings,clutches and bra!es, controls and drives, drive components,encoders and resolves, "ntegratedmotioncontrol, limit switches, linear actuators, linear androtarymotioncomponents, linearposition sensing, motors #both AC and DC motors$, orientation position sensing, pneumatics andpneumatic components, positioning stages, slides and guides, power transmission #mechanical$,seals, slip rings,solenoids,springs. Motors are the devices that provide the actual speed and torque in a drive system. Thisfamily includes ACmotortypes #single and multiphasemotors, universal, servo motors,induction, synchronous, andgearmotor$ andDCmotors#brushless, servomotor, andgearmotor$ as well as linear, stepper and air motors, and motor contactors and starters."n any electric motor, operation is based on simple electromagnetism. A current%carryingconductor generates a magnetic field& when this is then placed in an e'ternal magnetic field, itwill e'perience a force proportional to the currentin the conductor, and to the strength of thee'ternal magnetic field. As you are well aware of from playing with magnets as a !id, opposite#(orth and )outh$ polarities attract,while li!e polarities #(orth and (orth, )outh and )outh$repel. The internal configuration of a DC motor is designed to harness the magnetic interactionbetweenacurrent%carryingconductor andane'ternal magnetic fieldtogenerate rotationalmotion.*et+s start by loo!ing at a simple ,%pole DC electric motor #here red represents a magnetorwindingwitha-(orth-polarization, whilegreenrepresentsamagnet orwindingwitha-)outh- polarization$..very DCmotor has si' basic parts %% a'le, rotor #a.!.a., armature$, stator, commutator,field magnet#s$, and brushes. "n most common DC motors #and all that /eamers will see$, thee'ternal magneticfieldis producedbyhigh%strengthpermanent magnets0. Thestator is thestationary part of the motor %% this includes the motor casing, as well as two or more permanentmagnet polepieces.Therotor#togetherwiththea'leandattachedcommutator$rotateswithrespect to the stator. The rotor consists of windings #generally on a core$, the windings beingelectrically connected to the commutator. The above diagram shows a common motor layout %%with the rotor inside the stator #field$ magnets.Thegeometryofthebrushes, commutator contacts, androtorwindingsaresuchthatwhenpowerisapplied, thepolaritiesoftheenergizedwindingandthestatormagnet#s$aremisaligned, and the rotor will rotate until it is almost aligned with the stator+s field magnets. Asthe rotor reaches alignment, the brushes move to the ne't commutator contacts, and energize thene't winding. 1iven our e'ample two%pole motor, the rotation reverses the direction of currentthroughtherotorwinding, leadingtoa-flip-oftherotor+smagneticfield, anddrivingit tocontinue rotating. "n real life, though,DCmotors will always have more than two poles #three is a verycommon number$. "n particular, this avoids -dead spots- in the commutator. 2ou can imaginehowwithour e'ampletwo%polemotor, if therotor ise'actlyat themiddleof its rotation#perfectly aligned with the field magnets$, it will get -stuc!- there. Meanwhile, with a two%polemotor, there is a moment where the commutator shorts out the power supply #i.e., both brushestouch both commutator contacts simultaneously$. This would be bad for the power supply, wasteenergy, and damage motor components as well. 2et another disadvantage of such a simple motoris that it would e'hibit a high amount of torque3 ripple- #the amount of torque it could produce iscyclic with the position of the rotor$. )o since most small DC motors are of a three%pole design, let+s tin!er with the wor!ingsof one via an interactive animation #4ava)cript required$52ou+ll notice a few things from this %% namely, one pole is fully energized at a time #buttwo others are -partially- energized$. As each brush transitions from one commutator contact tothe ne't, one coil+s field will rapidly collapse, as the ne't coil+s field will rapidly charge up #thisoccurswithinafewmicrosecond$. 6e+ll seemoreabout theeffectsofthislater, but inthemeantime you can see that this is a direct result of the coil windings+ series wiring5There+s probably no better way to see how an average dc motor is put together, than by7ust opening one up. 8nfortunately this is tedious wor!, as well as requiring the destruction of aperfectly good motor.This is a basic 9%pole dcmotor, with , brushes and three commutator contacts.3.2 L293D IC (DC MOTOR DRIVER)::"18;.5 *,