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WWW.MWFTR.COM EECE404 Senior Design II Electrical and Computer Engineering Instructor: Dr. Charles Kim HOWARD UNIVERSITY
Senior Design Final Report Autonomously Mobile Air Purifier
Submitted by: Raymond Jones Warren Spencer Kenneth Booker Von Miles Charles Brown
Instructor: Dr. Charles Kim Date Submitted:04/23/2014
Seenior Deesign Final Report ͟͠͞ ͟͢ Mobile e Air Purrifier We certiffy that this is i an accurate Final Rep port and we are in agreeement that tthis report is an accurate representation of the project. p
________ ____________ ___________ ____________ __________________________________________________ Name N Sign ature Daate
________ ____________ ___________ ____________ __________________________________________________ Name N Sign ature Daate
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I ceertify that thiis report is an n accurate representation n of the projeect and I apprrove it.
________ ____________ ___________ ____________ __________________________________________________ Advisor/Instru A uctor Name Sign ature Daate
Seenior Deesign Final Report ͟͠͞ ͟͢ Conten nts Introducttion .................................................................................................. .................................................. 3 Problem Formulation n and Curren nt Status of Art .................................... .................................................. 4 nts and Crite eria of the Design D Requiirements .......................... .................................................. 5 Constrain Solution Generation and Selectio on of Top De esign ................................. .................................................. 7 Implementation of the Top Design............................................................ ................................................ 10 Performa ance Analysiis and Evalua ation of the Project ........................... ................................................ 13 Simulattion/Experimental ............................................................................ ................................................ 13 Evaluattion against th he design req quirements .............................................. ................................................ 14 Conclusio on ..................................................................................................... ................................................ 15 Recommendations ........................................................................................ ................................................ 15 ces..................................................................................................... ................................................ 17 Referenc Appendix x ......................................................................................................... ................................................ 18 Arduino o Mega 2560 Code ........................................................................... ................................................ 18 Copy Of O Final Proposal ................................................................................ ................................................ 23
Seenior Deesign Final Report ͟͠͞ ͟͢ Introduction The T air inside the home is generally dirrtier than air outside sincee a house is a closed-off environm ment. For thosse with allerg gies or asthm ma this poses a big problem m. Forced airr and heatingg systems only o circulatee dust particles and other pathogens arround the houuse. Currentt air purifierss in
the market are station nary or just oscillate o from m side to sidde like a fan.. There is a hhigh chance that the air pu urifier is justt filtering thee available air a in the room m and, thereefore, more aair purifiers may have to be b installed to filter the whole w house---depending on the size of course. M Most purifierrs today aree always running and hav ving to buy multiple m is a major inconnvenience too the customerr. With mucch thought, th he idea to make m a mobilee purificatioon device cam me about aftter looking at a the design ns for the auttomatic vacu uum. The moobile air purrifier will bee relatively thhe same con ncept except instead of cleaning c the floors this ddevice will bee cleaning thhe air. Air A purifiers are a devices th hat eliminate contaminantts from the aiir, thereby innstigating a cleaner, safer s environm ment. These devices are commonly c m marketed as bbeing beneficial to allergyy sufferers and asthmatiics, and at reducing or eliiminating seccond-hand toobacco smokee. Commercial grade air purifiers are manufactureed as either small stand-allone units orr larger units that can be affixed to o an air handller unit (AHU U) or to an HVAC H unit foound in the m medical, industrial, and commercial industriess. Air purifierrs may also be b used in inddustry to rem move impurities such as C CO
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from air before b processsing. Dust, pollen, p pet daander, mold sspores, can aact as allergenns, triggeringg allergies in i sensitive people. p With the advancem ment in technnology, air ppurifiers are bbecoming increasing gly capable of o capturing a greater num mber of bacteerial, virus, aand DNA dam maging particulattes. Air puriffiers are used to reduce the concentratiion of these aairborne conttaminants annd can be useful for people who w suffer fro om allergies and asthma. T There are maany types of aair purifiers; the mmonly used are s a filter--based purification whichh trap airbornne particles bby size exclussion. most com Air is forced through a filter and th he filter physsically capturres particles aand electroniic air cleanerrs use
Seenior Deesign Final Report ͟͠͞ ͟͢ an active electronicallly enhanced media m to com mbine elemennts of both ellectronic air ccleaners and passive mechanical m fillters designs.
Proble em Formulation and a Currrent Stattus of Arrt I.. Understan nding Probllem: Air po ollutants aree hazardous to those innhabiting thhe air space. EP PA states thaat some toxicc chemicals released r in thhe air such ass benzene or vinyl chloridde are highly toxic and can cause cancerr, birth defeccts, long term m injury to thhe lungs, as well as brainn and mage. Each day, d air pollu ution causes thousands off illnesses leaading to lost days at worrk and nerve dam school. III. Identified Need: A sy ystem that iss able to purrify the air reeliably, efficciently, selecttively and simplly. IIII. Research h the Statuss of Art: Cu urrently, in thhe market thhere are alreeady high-tecch air purifiers.
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Airocide A
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Oreck O Airstinccts
Note: Observations sh howed that bo oth air purification units aare stationaryy and are lim mited to one rroom. V. Determin ne our Requ uirements: We W want to fu further improove on the cuurrent air purrifiers IV by makin ng them ablle to detect air-quality in i multiple rooms and move towarrds the sourrce of corrupted d air by using a wide range of traansmitters, ssensors, receeivers, a moobility kit, aand a processorr. Maneuverrability, Reliaability, cost efficiency, e annd simplicityy are the goalls to reach foor this system’s design.
As A of today, Air purificaation comes in many foorms such aas UV germ micidal irradiation, activated carbon mesh hes, ionizers,, and much more; m howevver, none thatt was researcched seemed to be o the markeet are stationnary and it is interestingg to note how w this mobile. So far, all air purifiers on
Seenior Deesign Final Report ͟͠͞ ͟͢ project’s idea has not been implem mented as off yet. Here aare some exam mples of currrent stationaary air purifiers:
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Airocide—the A e harmful gaasses emitted d by productts in the hom me (cleaningg supplies, ppaints, ev ven air fresh heners) are concentrated d in the purrifier’s denssely packed matrix of hhighly reeactive cataly ysts that destrroy the patho ogens on conntact. Nothingg captured, nnothing cleanned.
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Oreck O AirInsttinct 200—haas a sensor th hat checks thhe particles inn the air passsing through it and au utomatically changes the airflow rate of the purifieer.
Constrraints an nd Criterria of the e Design Require ements The T system iss required to o be fully auttomated and,, in order to do that, we need a base with a motor, a motor con ntroller, ultraasonic sensorrs, IR Beacoons, and a M Microcontrolleer. We plann to have thiss device locaate various aiir-quality sen nsor arrays iinstalled around the hom me that read unclean air a using a gas sensor an nd a dust sensor. The arrray will havee its own beaacon and microcon ntroller.
The desig gn schematicc is the follo owing imagee:
Seenior Deesign Final Report ͟͠͞ ͟͢
The curreent design off the device has the follo owing constrraints: •
Poor maneuverability: Due D to the usee of only onee ultrasonic sensor the ddevice has m many blind spots in n which it wo ould not deteect obstructioon a certain angle away from it.
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No N selectivity y: On ECE day d we only used one sennsor array foor a demo; hhowever, if w we were w to have two arrays and a both werre activated tthe device w would not knnow which one had a higher precedence p to t go toward ds.
Seenior Deesign Final Report ͟͠͞ ͟͢ •
Motor M controller inefficieency: As of right r now thee device hass a motor conntroller that is on nly able to spin s the moto or forward. The second motor contrroller does nnot have this prroblem thankfully.
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Energy E inefficiency: Thee IR beaconss we got did not have a location/proxximity detection feeatures that would w allow w the beacon to know whhen they werre in close prroximity of eeach otther. As a reesult when th he device go ot close to thhe sensor arrray’s beacon it would spiin arround contin nuously searching for thee IR Beaconn location; thherefore, neeedlessly ex xpending en nergy.
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Floor restricteed: There sh hould only bee one mobilee air purifierr system in a one story home. It wou uld not be co ost effective to buy multiiple mobile aair systems; furthermoree, at th his point it may m cause co ommunicatio on problems..
Solutio on Generation and Selecction of T Top Desiign A great engin neering soluttion is one no ot only based on demandd but also fuunctionality, simplicity y of use, com mpliance to necessary n sttandards andd its capabilitties. Consideering these objectivee functions helped h to soliidify the idea of what th e mobile airr purifier shoould be able to do. To geenerate a greeat mobile aiir purifier, alll of the objeective functions were im mplemented iin the design off the mobile air purifier. In n terms of itss functionaliity, the mobiile air purifieer must sensse when the aair-quality inn a given env vironment reeaches valuees below an assigned a threeshold valuee. Furthermoore, when thee airquality value goes beelow the threeshold, the mobile m air puurifier must aalso successffully travel ffrom nt location to o the vicinity y of whereveer the poor aair-quality reeading is deteected; that iss, its curren provided d that the terrrain is flat an nd agreeablee enough for the device tto travel on w without caussing
Seenior Deesign Final Report ͟͠͞ ͟͢ any problems. When multiple areeas report vaalues below tthe thresholdd value, the mobile air purifier design d must be able to diistinguish wh hich area, iff any, has thee greatest degree of air pollution n. Another A key feature f in the mobile air purifier dessign is its useer interface. The mobile air purifier must m have an n easy interfaace that will allow the usser to set hiss desired threeshold valuee that will alertt the mobile air purifier that t the air within w a certaain area is poolluted. Alsoo, the user interface will allow the user to eaasily turn thee mobile air purifier on aand off. The mobile air purifier must m be capaable of avertiing obstacles in its direcct path and comply with the latest standardss for purificaation rate.
The follo owing table depicts d the objective o fun nctions that w we desired thhe mobile air purifier to fulfill.
Seenior Deesign Final Report ͟͠͞ ͟͢ After A selectin ng the objecttive function ns that the moobile air purrifier will meeet, the next phase of solution gen neration is to o choose whiich device coomponents bbest fit the reequirements of gn. In trying to select an appropriate chassis for tthe mobile aiir purifier deesign, the coost, the desig maneuveerability, max ximum paylo oad, reliabiliity and poweer consumpttion were alll criteria used to distinguish the best option. o Deveeloping a deccision matrixx and ranking the variouus options maade it even easiier to decidee which chassis was best. Likewise, iin selecting a device thatt would deteect obstacless in the path of the mobille air purifieer, the cost, ppower consuumption, reliability, compatib bility, accuraacy, range an nd ease of prrogramming are all factoors that weiggh into the decision. The T following g table depiccts the variou us options foor the robot chassis and their scores based on certain criteeria. = not good, 2= ok, 3= grreat 1=
Seenior Deesign Final Report ͟͠͞ ͟͢ The T following g table depiccts the variou us options foor obstacle ddetection andd their scores based on certain criteeria. 1= = not good, 2= ok, 3= grreat
Implem mentatio on of the e Top De esign The T decision matrix helpeed in selectin ng the best pparts for the mobile air-qquality desiggn. The PING G ultrasonicc sensor is ussed to detect obstacles upp to 3 meterss away from m the base. Thhis sensor haas an output pin that is co onnected to the microcoontroller whiich in turn caalculates the distance an object is away from the t mobile air purifier. T Two 12VDC C motors are connected too the uk1122 motor m contro oller which, in i turn, is alsso connectedd to the samee microcontrroller. The
Seenior Deesign Final Report ͟͠͞ ͟͢ microcon ntroller send ds signals to the t motor co ontroller thatt commands the motors tto go forwarrd, stop or sp pin opposite of each otheer. An IR traansceiver is aalso seated oon the mobille air purifier chassis, acting a as a co ompass that will direct the t base to a given air-quuality sensorr array. A 122V, 7amph baattery suppliies power to the motors.
The T following g image is of the compleeted robot chhassis with aall componennts mounted.
As A for the air-quality senssor array, thee MQ 135 ggas sensor waas chosen inn the final implemen ntation of th he solution du ue to its abillity to detectt a wide rangge of problem m gases including g smoke, ben nzene and am mmonia. Thee IR beacon on the air-quuality sensorr array matcches the IR beeacon on the mobile air purifier p basee. When the ttwo IR beacons detect each other, thhe mobile aiir purifier will respond by b traveling to the locati on of the airr-quality sennsor array.
Seenior Deesign Final Report ͟͠͞ ͟͢ The T following g image is of the compleeted air-quallity sensor arrray with all componentss mounted.
The T combinattion of air-qu uality sensorr array and tthe mobile aiir purifier baase is what makes th he complete design d of thee mobile air purifier. Wiith the air-quuality sensorr array, the bbase can sensee the condition of the airr in multiple rooms simuultaneously.
Seenior Deesign Final Report ͟͠͞ ͟͢ The T following g image is of the compleeted robot chhassis and aiir-quality sennsor array.
Perforrmance Analysis A and Evaluation o of the Prroject Simulatio on/Experim mental The T autonomously mobile air purifierr has three m main operatinng functionss; that is, it detects co ontaminantss in the air arround it, mov ves autonom mously throuugh its enviroonment and purifies the t air. In ord der to accom mplish these objectives aand also meeet the specifications laid out in the dessign of the device, d a suitte of tests wiill be develooped and impplemented. T These tests w will occur durring differen nt stages of the t design’s execution. L Listed below w are some off the tests thhat will be ap pplied and expectations:: Parts tesst
Seenior Deesign Final Report ͟͠͞ ͟͢ Before an ny part or co omponent is used in the execution e off the design, it will be riggorously testted to make sure s it functiions properly y. Each part is expected to work in ccompliance w with its factoory standard.. Obstruction sensing g and reroutting test The device senses ob bstructions a certain distaance away fr from its surfaace. Once the device classifiess something as an obstru uction, it calcculates anothher route to ttravel along..
Sensory test The device sensed th he level of co ontaminants in the air annd then traveels to that desstination if possible.
Speed off mobility teest The device move at the t speed speecified in thee design speecifications.
Battery life l test The device function continuously c y at the batteery life speciified in the ddesign speciffications.
Evaluatio on againstt the design requirem ments The T system ev valuation reacches the goall that we requuired and thaat fully autom mated and to do that we need a base with w a motor, a motor conttroller, ultras onic sensors, IR Beaconss, and a ocessor. We plan to have this device locate activatted air-quality ty sensor arraays installed Micropro around th he home that read unclean n air using gaas sensors andd dust sensorrs. The arrayy will have itts own beaccon and micro oprocessor.
Seenior Deesign Final Report ͟͠͞ ͟͢ Conclu usion We W believe th hat the devicce will have the t highest eefficiency inn removing pparticles from m the indoor en nvironment. It will signifficantly redu uce indoor aiir pollution aand the ensuuing haze rissk if operated properly. Th he device wiill be cost-efffective, not only in purcchase, but also in maintenaance (power,, filter chang ge, etc.). Thee mobility off the device w will reduce iindoor haze pollution n in multiple rooms in thee house/aparrtment settinng. The mostt practical usse of the purrifier will be to o reduce indo oor pollution n in one or tw wo rooms onnly; most suuitable, parennts and childdren’s sleeping rooms. The air purifier will w spend most m of the ddaytime in roooms during high outdooor pollution n levels. For those living in an area with w high bacckground paarticle concenntrations, as present in n most metro opolitan areaas, this desig gn will be recommendedd to permaneently improvve indoor qu uality.
Recom mmendattions For future fu iteratio ons of this prroject, there are a few thhings we recoommend. W We recommennd the follow wing: •
Finding a way y to implement multiple sensor arrayys within thee system.
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Adding A a ring g of ultrason nic sensors arround the baase so that thhe device hass a better scoope of vision.
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Replacing R thee motor conttroller that iss only able too give a forw ward responsse with one tthat caan give a rev verse respon nse.
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In nstalling pro oximity senso ors to the system so thatt the device kknows exacttly how closee it is to o the air-quaality sensor arrays. a
Seenior Deesign Final Report ͟͠͞ ͟͢ By doing g these chang ges, the true objective off providing cclean air arouund the hom me will be achieved d.
Seenior Deesign Final Report ͟͠͞ ͟͢ Refere ences Works W Cited "How to use 315Mhzz RF transmiitter and receeiver modulees with arduuino." BUILD D CIRCUIT.. N.p., N n.d. Weeb. 23 Apr. 2014. 2 . "HowStu uffWorks "H How Air Puriifiers Work"." HowStuffW fWorks. N.p.,, n.d. Web. 223 Apr. 20144. . "Oreck ® AirInstincct® 200." Oreck. N.p.,, n.d. Web. 223 Apr. 20144. . "PING)))) Ultrasonic Distance Seensor." Paralllax Inc. N.pp., n.d. Web.. 23 Apr. 2014. . "Pololu IR I Beacon Transceiver." T " Pololu IR Beacon B Trannsceiver. N.pp., n.d. Web. 23 Apr. 20114. . "REX-14 4D Round Robot Base w/ w HP Encod ders." REX-1 4D Round R Robot Base w w/ HP Encodders. N.p., N n.d. Weeb. 23 Apr. 2014. 2 . "airocidee® Better Air. A Better Life.â„¢." L Airrocide. N.p.,, n.d. Web. 223 Apr. 20144. .
MLA form matting by BibMe.org. B
Seenior Deesign Final Report ͟͠͞ ͟͢ Appen ndix Arduino Mega M 2560 0 Code //Ultrason nic Sensor In nput int pingPiin1 = 4; //motor2 int FWB = 43; int ENB = 41; int BWB = 39; //motor1 int FWA= =35; int ENA= =33; int BWA= =31; //IR Beaccon Input int IRN=13; int IRS=1 12; int IRE=1 11; int IRW= =10; //Receiveer Pair Input void setup p () { Serial.beegin(9600); pinModee(ENA, OUT TPUT); pinModee(FWA, OUT TPUT); pinModee(BWA, OUT TPUT); pinModee(ENB, OUT TPUT); pinModee(FWB, OUT TPUT); pinModee(BWB, OUT TPUT); pinModee(IRN, INPU UT); pinModee(IRS, INPUT T); pinModee(IRE, INPUT); pinModee(IRW, INPU UT); } //ultrason nic sensor disstance result in i inches long inch hes1; //desired distance thatt the base sho ould stop awaay from an obbject int stoppiing_distance = 20; void loop p() { if(digitallRead(IRN) == = LOW) { beacon_ _detected(IR RN); } else if(diigitalRead(IR RS) == LOW W) {
Seenior Deesign Final Report ͟͠͞ ͟͢ beacon_ _detected(IR RS); } else if(diigitalRead(IR RE) == LOW W) { beacon_ _detected(IR RE); } else if(d digitalRead(IR RW) == LOW W) { beacon_ _detected(IR RW); } else { loiter_aalgorithm(); } } long PING_SIG(int piingPin) { // The PIING))) is trig ggered by a HIGH H pulse of o 2 or more m microsecondds. // Give a short LOW pulse beforehand to ensu ure a clean HIIGH pulse: pinModee(pingPin, OU UTPUT); digitalW Write(pingPin,, LOW); delayMiccroseconds(2 2); digitalW Write(pingPin,, HIGH); delayMiccroseconds(5 5); digitalW Write(pingPin,, LOW); pinModee(pingPin, IN NPUT); long duraation = pulseeIn(pingPin, HIGH); H // Accord ding to Paralllax's datasheet for the PIN NG))), there are // 73.746 6 microseconds per inch (i.e. sound traavels at 11300 feet per // second d). This gives the distance travelled by y the ping, ouutbound // and retturn, so we divide d by 2 to o get the distaance of the obbstacle. // See: htttp://www.paarallax.com/d dl/docs/prod/acc/28015-P ING-v1.3.pddf delay(10 00); return du uration / 74 / 2; } void loiteer_algorithm(() { inches1 = PING_SIG G(pingPin1); // N = NO O MOVEME ENT // P = BA ASE CAN PA ASS //CONDIITION 1 -- N boolean condition1 = (inches1 <= = stopping_diistance); //COND DITION 2 -- P boolean condition2 = (inches1 > stopping_dist s tance);
Seenior Deesign Final Report ͟͠͞ ͟͢ //N if (condittion1 == true) { while(in nches1 <= sto opping_distan nce) { spin(); inches1 = PING_SIIG(pingPin1)); } stop_no ow(); } //P else if (co ondition2 == true) { while(in nches1 > stop pping_distancce && digitaalRead(IRN) == HIGH & && digitalReaad(IRS) == H HIGH && digitaalRead(IRE) == HIGH && & digitalReaad(IRW) == HIGH) { forwarrd(); inchess1 = PING_S SIG(pingPin1); } stop_now w(); }else; } void beaccon_detected d(int Beacon) { inches1 = PING_SIG G(pingPin1); //if the no orth beacon is i detected an nd the path issn't clear, loiiter around if (Beaco on == IRN && & inches1 <= < stopping_d distance) { stop_no ow(); loiter_aalgorithm(); } //if north h beacon is deetected and th he path is cleear, go forwaard else if (B Beacon == IR RN && inchees1 > stoppin ng_distance) { inchess1 = PING_S SIG(pingPin1); while((inches1 > sto opping_distaance && digiitalRead(IRN N) == LOW) { forward(); inchees1 = PING_ _SIG(pingPin n1); } stop_now(); } else if (B Beacon == IR RS) { while (d digitalRead(IIRN) == HIG GH && (digitalRead(IRS ) == LOW||ddigitalRead(IRE) == LOW||dig gitalRead(IRW W) == LOW W)) {
Seenior Deesign Final Report ͟͠͞ ͟͢ spin(); } inches1 1 = PING_SIG G(pingPin1); while( inches1 i > sto opping_distan nce && digittalRead(IRN N) == LOW) { forward(); inchess1 = PING_S SIG(pingPin1); } stop_no ow(); } else if (B Beacon == IR RE) { while (diigitalRead(IR RN)== HIGH H && (digitalRead(IRS) = == LOW||diggitalRead(IRE E) == LOW||dig gitalRead(IRW W) == LOW W)) { spin(); } inches1 1 = PING_SIG G(pingPin1); while( inches1 i > sto opping_distan nce && digittalRead(IRN N) == LOW) { forwarrd(); inchess1 = PING_S SIG(pingPin1); } stop_now(); } else if (B Beacon == IR RW) { while (diigitalRead(IR RN)== HIGH H && (digitalRead(IRS) = == LOW||diggitalRead(IRE E) == LOW||dig gitalRead(IRW W) == LOW W)) { spin(); } inches1 1 = PING_SIG G(pingPin1); while( inches1 i > sto opping_distan nce && digittalRead(IRN N) == LOW) { forwarrd(); inchess1 = PING_S SIG(pingPin1); } stop_no ow(); } else; } void forw ward() { //left mottor forward digitallWrite(ENB, HIGH); digitallWrite(FWB,, HIGH); digitallWrite(BWB, LOW);
Seenior Deesign Final Report ͟͠͞ ͟͢ //rightt motor forwaard digitallWrite(ENA,, HIGH); digitallWrite(FWA, HIGH); digitallWrite(BWA A, LOW); } void spin n() { //left mottor forward digitalW Write(ENB, HIGH); H digitalW Write(FWB, HIGH); H digitalW Write(BWB, LOW); //right motor m backw ward digitalW Write(ENA, HIGH); H digitalW Write(FWA, LOW); digitalW Write(BWA, HIGH); } void stop_now() { //left mo otor stop digitalW Write(ENB, HIGH); H digitalW Write(BWB, HIGH); digitalW Write(FWB, HIGH); H //right motor m stop digitalW Write(ENA, HIGH); H digitalW Write(FWA, HIGH); digitalW Write(BWA, HIGH); }
Seenior Deesign Final Report ͟͠͞ ͟͢ Copy Of Final Prop posal HOWAR RD UNIVERSSITY
Sen nior Design D n Fin nal Proposal Au utonom mously Mobile Air P Purifierr
Subm mitted b by: Rayymond Jones Warrren Spencer Kenneth Booker Von V Miles Chaarles Brown
Seenior Deesign Final Report ͟͠͞ ͟͢
Table of o Conten nts Objective ......................................................................................................... ................................................ 26 Introduction .................................................................................................... ................................................ 26 Background ..................................................................................................... ................................................ 26 S ......................................................................................... ................................................ 27 Problem Statement Problem Formulation F ...................................................................................... ................................................ 27 Status of Art A .................................................................................................... ................................................ 28 Current Syystem Drawb back .............................................................................. ................................................ 28 Engineering Approache es ................................................................................. ................................................ 29 S ............................................................................................. ................................................ 29 Initial Solution System m diagram........................................................................................... ................................................ 30 Alternaative Approacches/Compon nents ........................................................ ................................................ 30 Require ed Knowledge e and Course Work ...................................................... ................................................ 31 Feasibilityy of Design ........................................................................................ ................................................ 32 Goals ................................................................................................................ ................................................ 32 Design Re equirements ...................................................................................... ................................................ 32 Movem ment................................................................................................... ................................................ 32 Sensorss ........................................................................................................ ................................................ 33 Purifierr ........................................................................................................ ................................................ 34 Air Quaality Detection System ...................................................................... ................................................ 34 Specificattions .................................................................................................. ................................................ 35 Goal Requ uirements ......................................................................................... ................................................ 36 Cost .............................................................................................................. ................................................ 36 Software ...................................................................................................... ................................................ 37 Hardwaare .................................................................................................... ................................................ 37 Testing an nd Verification Plan .......................................................................... ................................................ 38 Regulattions.................................................................................................. ................................................ 40 Project Management M ...................................................................................... ................................................ 40 Roles ............................................................................................................. ................................................ 40
Seenior Deesign Final Report ͟͠͞ ͟͢ Timelin ne....................................................................................................... ................................................ 40 Deliverables................................................................................................. ................................................ 41 Conclusio on ....................................................................................................... ................................................ 41 Reference es ...................................................................................................... ................................................ 43
Seenior Deesign Final Report ͟͠͞ ͟͢ Objectivve This T proposal is meant to present p and give g details onn the developpment of ourr electronic design. The devicce will be ablle to move arround on its own o while filltering the airr along the w way. The aim m is to improve upon u the efficiency of airr purification devices withh the hopes thhat this projeect will be seeen as something g that could actually a go on n the market.
Introdu ction There T is an auttomatic vacuu um that cleans the floor whhile being ablle to avoid, m move around aand go under certain obstacless. However, there t is no aiir purifier likke this on the market. Moost air purifieers are stationary y and generally oscillate from fr side to side s just like a fan. There is a high chhance that theese air purifies are a just filterin ng the availaable air in thee room. Addiitional purifieers may havee to be installed to filter the whole w house depending on n the size of the living sppace. The mobbile purificattion device thhat we came up with w is design ned to hold an nd supply pow wer to an exissting purifier, but is also abble to move aaround obstacles for maximum m space efficieency and deteect areas wherre air is denseest.
Backgro ound The T air inside the t home is generally g dirtiier than air ouutside since a house is a cloosed-off environment. Air puriffiers are used to reduce the concentratioon of these airrborne contam minants and caan be useful forr people who suffer s from alllergies and asthma. a Theree are many typpes of air puriifiers; the moost commonly y used are filtter-based puriification whicch traps airboorne particles by size excluusion. Air is fo forced through a filter and thee filter physicaally captures particles. Eleectronic air cleaners use ann active electroniccally enhanced d media to co ombine elemeents of both ellectronic air ccleaners and ppassive mechaanical filters dessigns. For thosse with allerg gies or asthmaa this poses a big problem. Forced air annd heating syystems only circu ulate dust partticles and other pathogens around the hoouse. Purifierrs are devicess that eliminatte contaminaants such as dust, d pollen, pet p dander and d mold sporess from the airr, thereby creaating a cleaneer,
Seenior Deesign Final Report ͟͠͞ ͟͢ safer enviironment. Witth the advanccement in tech hnology, the ppush for moree advanced aiir purificationn units is being made m but puriffiers have nott yet been auttonomously m mobile.
Problem m Statemen nt Typical T home air purifiers are a generally stand-alone uunits which, bby nature, havve a restrictedd coverage area and theirr rated for maaximum coverrage area is bbased on a squuare room connsidering no obstructio ons to the airfflow and no aiir contaminattion problemss. Our air puriifier will be aable to detect tthe airflow paatterns and the size and shaape of a room m while maneuuvering arounnd obstructionns, all factors that affect cov verage area.
Problem m Formula tion I. Undersstanding Pro oblem: Air po ollutants are hazardous too those inhabiiting the air sspace. EPA states that somee toxic chemicals released in the air such as benzenne or vinyl chhloride are higghly toxic annd can cause can ncer, birth deffects, long term m injury to th he lungs, as w well as brain aand nerve dam mage. Each daay, air pollution causes thousaands of illnesses leading to o lost days at work and schhool.
II. Identified Need: A system that is able to purrify the air.
III. Resea arch the Stattus of Art: Cu urrently, in th he market therre are alreadyy high-tech airr purifiers. -
Airoccide
-
Oreck Airstincts
Note: Obsservations sho owed that botth air purificaation units aree stationary annd are limitedd to one room m.
Seenior Deesign Final Report ͟͠͞ ͟͢
IV. Deterrmine our Requirements R s: We want to o further impprove on the current air puurifiers by m making them ablee to detect airr quality and d move towarrds the sourcee of corrupteed air by usinng a wide rannge of transmitteers, sensors, reeceivers, mob bility kit, and a processor.
Status of o Art Air A purificatio on comes in many formss such as U UV germicidaal irradiation,, activated ccarbon meshes, io onizers, and much m more; however, h none that was ressearched seem med to be moobile. So far all air purifiers on the mark ket are statio onary and itt is interestinng how thiss project’s iddea has not been implemen nted as of yet. Here are som me examples of current staationary air puurifiers: Airocide— —the harmfu ul gasses emiitted by prod ducts in the home (cleanning suppliess, paints, eveen air freshenerss) are concen ntrated in thee purifier’s densely d packked matrix off highly reacctive catalysts that destroy th he pathogens on o contact. Nothing N capturred, nothing ccleaned.
0—has a sensor that ch hecks the paarticles in thhe air passinng through iit and Oreck AiirInstinct 200 automaticcally changes the airflow raate of the puriifier.
Currentt System Drrawback Available A air purification p systems s are all stationary and can onlyy purify the aair within a ccertain space. Th he air from around a the ho ouse does cirrculate and w will eventuallly reach the room that thhe air purifier iss in; howeverr, that may taake a considerrably long tim me. Air polluutants need too be removedd from the air ass soon as possible. One could c place multiple m air ppurifiers arouund the housse but, takingg into considerattion the costt and energy y needed to buy b and suppply those unnits with elecctricity, it may be inconveniient to some consumers. Therefore, to o meet the neeeds of those consumers, we want to ddesign
Seenior Deesign Final Report ͟͠͞ ͟͢ one system m with the ab bility to detect areas in th he house or a building witth the densesst air pollutioon and move itself to the locattion to filter th he air.
Engineeering Apprroaches The T aim of ourr solution app proach is to deesign a mobille device that will be able tto avoid obstructio ons and ledgess while navig gating through h any environnment, whetheer it’s an aparrtment space oor a home. The device draw ws upon severral inputs prov vided by an aarray of sensoors which assiist in the device’s guidance ability and itss ability to deetect the qualiity of air in ann environmennt. Multiple seensor arrays w will be placed throughout a given area to o sense air qu uality while thhe sensors thaat assist in thee device’s navigation n will be placced directly on n the device. The air qualitty sensor arraays will detect foul air and the device will attempt to navigate n from m its present lo ocation (poinnt A) to the vicinity of whicchever air quaality sensor arrray detects thee worst air qu uality (point B). B Initial Solu ution Th here was no question q that, in terms of ch hoosing a proocessor to hanndle data retrieval and computing g, our team would w utilize the t Intel De2ii-150. This prrocessor will bbe the focal ppoint of our design. Ou ur project also depends on n using a comb bination of seensors to funcction effectiveely. Out of thhe thousandss of sensors on n the market today, we had d to select thee few that woould best fit ouur project’s goals. For our aiir quality senssor array, we wanted senso ors that wouldd detect bad aair at a very acccurate degreee of precision. We also waanted our air quality q sensorr to be able too cover the scoope of an entiire room. Thereforee, we decided to focus look king at the den nsity of air inn a given enviironment to help us determ mine the degreee of air contam mination. Den nsity is a funcction of presssure and tempperature. Air ppressure is a characteriistic that doess not vary thro oughout an arrea so when fo foreign contam minants comee and interferee with the expectted air pressu ure or air temp perature, the air a density in the environm ment will channge. The air pressure and a air temperrature values picked up by y the air qualitty sensor arraays will be traansmitted
Seenior Deesign Final Report ͟͠͞ ͟͢ wirelessly y to the De2i-150 which co ollects that daata, compares it to the ideall air density aand interpretss the percentag ge error betweeen the valuess to mean thatt the air has bbeen contaminnated by that eextent. Furthermo ore, the mobile device willl rely on an in nfrared sensorr and an ultraasonic sensor to navigate. T The infrared seensor will dettect obstacless in the path of o the mobile m machine and the ultrasonicc sensor will detect thaat the device may m run into. System diagram
Alternativve Approache es/Componen nts
Seenior Deesign Final Report ͟͠͞ ͟͢ As A an alternatiive solution ap pproach we considered c usiing an actual air quality seensor instead oof an array of seensors. This would w decrease the topolog gy and parts nnecessary for this network. In terms of aair quality sensors, we loo oked at the SaainSmart MQ1 135 Air Qualiity Sensor forr Hazardous G Gas Detectionn. However,, after conduccting more ressearch into thee product we realized that hazardous gaas must be extremely y close to the sensor for it to t pick up on any deviationn in air qualitty.
W Required Knowledge and Course Work r some concepts c from m chemistry cconcerning deensity. We alsso For this projecct, we had to relearn t De2i-150 which is the heart of our ddevice. Also, knowing the have to atttain a level of mastery of the concept of the Ideal Gaas Law helped d to narrow down d the typee of sensors w we wanted to uutilize. The iddeal air density y can be calcu ulated using the t equation below. b
ure at a given altitude from m sea level. Inn different parrts of Americaa, the value oof Ph Ph is the pressu will vary. R-specific iss a constant an nd T is the tem mperature meeasured by thee temperaturee sensor. Oncee the ideal valu ue for the air density d is com mputed by thee processor, thhe air density in the home is computed uusing the same general g formu ula for density y.
Seenior Deesign Final Report ͟͠͞ ͟͢ In n the equation n above p is th he air pressurre measured bby a given air pressure senssor. T is the temperatu ure measured by a given tem mperature sen nsor. Taking the percentagge error of thee two density values willl tell the degree of air con ntamination att a given senssor array.
Feasibillity of Desiign This T project is not an easy task t if you weere trying to bbuild the air ppurifier from sscratch becauuse that’s not our expertisee. Our knowleedge goes into o building thee mobile machhine, which iss not simple bbut has steps that t can makee the process go smoother.. While usingg our intel atom m board and sensors to program the t machine where w it can go g throughoutt the area. Thee air purifier ccan just turn oon and off whhen it needs to purify p the areaa which, we will w be able to o do with the sensors and ssome rewiringg with the inteel atom boarrd.
Goals Our O goals are to t create an air a filtration system s that coontrols itself ccompletely. Our hope witth our air purifieer is to increase upon the efficiency e of most m filtrationn units as set by the Deparrtment of Eneergy’s standard for f removing g troublesomee particles fro om the air. W We are also working tow wards a device that moves aro ound at a resspectable speed, moving from f problem m area to problem area wiithout much issue. Last but not n least, we are a attempting g to set up a rechargeable r ssystem that iss capable of ddetecting wheen it is low on po ower and mov ves back to itss charging staation in order to recharge itt.
Design Requireme R ents Movemen nt The T mobile maachine is designed with fou ur wheels andd will be able to perform thhe following motion co ommands: forrward, reversee, forward lefft, forward rigght, reverse leeft and reversee right. The autonomo ous air purifieer’s movemen nt will be dictaated accordinng to the logicc listed below w:
Seenior Deesign Final Report ͟͠͞ ͟͢ 1.
Iff at any point in time the aiir purifier’s battery life is bbelow 10% thhen the air puurifier will
automaticcally attempt to t return to itss charging baase if possiblee. 2.
The T air purifier is equipped with strategically placed ssensors that ccontinuously ccollect data frrom
the enviro onment around the device. The device uses u the sensoors to find a diirection with no immediatee obstacles//cliffs and theen moves in th he direction of o that path. 3.
Iff the device seenses an obstaacle or cliff a distance of 112 inches or leess away andd the obstacle//cliff
is along th he device’s travel path then n the device stops s and waiits 2 seconds. 4.
Iff the device no longer senses the object after 2 seconnds then the obbstacle/cliff is considered non-
stationary y and the deviice will contin nue along its path. p a.
Iff the device seenses the objeect after 2 secconds then thee device definnes the path aas a FAILED route
and begin ns to store a teemporary log of its FAILED paths, prevventing the deevice from puursuing the sam me path again n. b.
When W attemptiing to change course, the liimit on the diistance that thhe device can approach an
obstacle teemporarily deecreases from m 12 inches to o at most 2 incches. c. i.
The T device theen attempts to o turn 45⁰ clocckwise then rrepeats steps 1 – 3. Iff the device gets within 2 in nches of an obstacle o whilee attempting tto turn then thhe device rem mains
in its current location for f ten minutees, resets its path p log and thhen tries to finnd a new pathh. d.
Iff the device fiinds a free patth then it retu urns to its defa fault settings aand continuess moving forw ward. Iff the device caannot find a new n path afterr 4 iterations of step 4b theen the device remains in its
i.
current location for ten n minutes, resets its path lo og and then triies to find a nnew path. Sensors The T system usees a few types of sensors to aid in its opperation. Abooard the mainn unit, there arre the ultrasonicc sonar sensorrs and the infrrared sensors.. The sonar seensors are useed to determinne if there aree any obstructio ons are in the traveling path h of the unit by b sending ouut an ultrasoniic signal and checking the time
Seenior Deesign Final Report ͟͠͞ ͟͢ it takes fo or the signal to o return. Thee infrared senssors are used to edge detecction so that tthe unit does nnot moving off the stairs an nd therefore would w be placced on the un derside of thee unit. Purifier The T purifier ussed will be ab bsorbent and with w the use oof a vacuum itt will take in air and absorrb the air pollutaants that pass through. Air Quality Detection System S The T smart grid d unit will hav ve a detection n screen that ddisplays the ddegree of air ppollution withh respect to the ideal leveel of good airr quality. The detection scrreen will also display the bbattery level oof the device perriodically. Th here will be trransmitters ou utfitted with bbarometers annd thermomeeters around thhe house whiich will alert the mobile pu urifier that theere is a changge in air qualiity. The transsmitter that measures the greatest deviation d of standard air qu uality will be prioritized byy the system, and it will heead to the room where w the transmitter is in nstalled.
Sensor Array Input
Temperature Data from arrrays 1-N Air Pressure Data from arrrays 1-N
Output
Proce essing data too comp pute the true air densiity for the N aair qualitty sensor arraays
Takingg percentage error of o true air densitty against thee ideal air a density
Device movves to the desired locaation with the greeatest percentage error
Device reroutes and goes to o another location if fiirst location can nnot be reached
Seenior Deesign Final Report ͟͠͞ ͟͢
Unit’s Sensor Input Ultrason nic sensor Data Infrared d sensor Data Dete ecting Obstrucction Deteccting Ledges Routiing…
Specificcations
Mobility y Speed
presu umably 1.5 in n/s need to be tested
Purifier Speed
-
Battery Life L Expectan ncy
2 hrss. (if constantlly operating)
Seenior Deesign Final Report ͟͠͞ ͟͢ Battery Type T
Rech hargeable 6-ceell Lithium Ioon Battery Paack
Wheel Diameter D
3 in.
Wheel Width W
1.18 in.
Base Measurement
9.36 in (length) x 9.09 in (widtth) x 2.82 in ((height)
System weight w
10-12 lbs.
Goal Re quirementts Cost In n order to con nstruct our auttonomous air filtration uniit, we need m materials that sshould cost uss a total of $3 300 (change this once you find a fan, staand, and batteery unit).
Parrt Name
Vend dor
Unit Pricee
Q Quantity
Total Price
Barometer
eBa ay
$31.00
4
$1244.00
Seenior Deesign Final Report ͟͠͞ ͟͢ HC C-SR04
eBa ay
$3.99
4
$155.96
Banana Robotics R
$0.99
1
$0..99
SainSmart
$45.99
1
$455.99
$99.99
1
$999.99
$3.03
4
$122.12
Total
$2999.05
Ultraso onic Module
TCRT T5000L IR Infrareed Reflective Senso or (2 pack)
4WD Drive D Robot Chassis C
Adso orbent Air Purifier
Therrmometer
eBay..com
Software Since this unit shall be autonomous, we will w have to cconstruct a coode using C ass our main language in order for itt to operate. There T are threee main conceentration poinnts that the coode will be concentraating on: the sensing, the pu urifying, and the movemennt. The unit sshall pan for aany deficienccies in air quality y and if it find ds any, it shalll move towarrds the generaal location and turn on the fan so that it may draw in aiir so that it may be pulled through t the fiilters. The unnit will be equuipped with seensors so thatt it would be able to perforrm this trackiing function, as a well as navvigate areas aand avoiding eedges. Hardware e
Seenior Deesign Final Report ͟͠͞ ͟͢ For this device, we require three differeent types of ssensors. The first sensor, tthe air qualityy sensor, is the main com mponent in maaking the systtem operationnal. This senssor will be ussed to check ffor impurity in i the air and then assisting g in the decisiion of when tto turn the filttration unit onn and off. Thhe second typ pe of sensor, the sonar sen nsor, is used for fo the purposse of mobilityy. The sonar emits a sound inaudible to the human n ear and checcks to see wheen the sound returns. By ddoing this, it ddetermines thee distance between b the fiiltration unit and a an obstru uction that woould inhibit itss movement aand therefore assists in knowing whaat direction to o turn. The fin nal sensor, thhe infrared refflective sensor, will be used to detect edg ges or, in this case, stairs. By producing g a signal andd waiting for iit to return, thhe unit can telll whether or o not it is neaar stairs and th herefore know w when to beggin reversing. We also havee the base of the t unit which h contains whheels capablee of 4-wheel ddrive. This w way, the unit will w have moree free range of motion wheen moving aroound. In ordeer to draw in tthe air for purificatio on, we would d require a fan n and to purify y the air, we w would need a few filters. T The system w will be controlled d through the use of an Ard duino Mega microcontrolle m er and the Inttel Atom Boarrd.
Testing and Verifiication Pla an The T autonomously mobile air a purifier haas three main operating funnctions; that is, it detects contaminaants in the airr around it, moves autonom mously througgh its environnment and purrifies the air. IIn order to accomplish theese objectivess and also meeet the specifiications laid oout in the desiign of the devvice, a suite of teests will be deeveloped and implemented d. These tests will occur duuring differentt stages of thee design’s execution. e Lissted below aree some of thee tests that willl be applied aand expectatiions:
Parts test Before an ny part or com mponent is useed in the execcution of the ddesign, it willl be rigorouslyy tested to maake sure it fun nctions properrly. Each partt is expected to t work in co mpliance witth its factory sstandard.
Seenior Deesign Final Report ͟͠͞ ͟͢
Obstructio on sensing an nd rerouting teest The devicce is expected d to sense obsttructions a ceertain distancee away from iits surface. Once the devicce classifies something ass an obstructio on, it calculattes another rooute to travel aalong.
Autonomo ous charging test The devicce is expected d to automaticcally return to o a charging bbase when its battery life iss 10% or beloow.
Sensory teest The devicce is expected d to sense the level of contaaminants in thhe air and theen travel to thaat destinationn if possible.
Purificatio on rate test The devicce is expected d to purify thee air in the env vironment at tthe rate speciified in the deesign specifications.
m test Speed of mobility The devicce is expected d to move at th he speed speccified in the ddesign specificcations.
Seenior Deesign Final Report ͟͠͞ ͟͢ Battery liffe test The devicce is expected d to function continuously c at a the battery life specifiedd in the designn specificatioons. Regulations There T are diffeerent regulatio ons and stand dards we mustt abide by whhen we considder designing the actual harrdware itself. For example the air purifieer must removve 99.97% off 0.3 micromeeter particles which is a standard forr the air purifiier we decided d to use. Alsoo the most staandard househhold has a staandard output of 15 to 20 amp ps (which you u shouldn’t ex xceed 80% of said amount)) so we must stick to such standard when w construccting the charrger as well as any other poower sources we will needd.
Project Managem ent Roles ng and Remotte Device Pro ogramming: C Charles Brow wn and Von M Miles Main Unit Programmin
nstruction of Machine M and Installation oof Sensors: W Warren Spenceer, Raymond JJones Hardwaree Design, Con and Kenn neth Booker Timeline
Seenior Deesign Final Report ͟͠͞ ͟͢
Deliverables Once O we have completed th his project, wee will have a m main unit thaat can move arround the houuse based on a signal that is i being transm mitted from one o of our rem mote units andd would beginn to clean thee air within that particular room r before moving on to o another room m to repeat thhe process. A As such, our uunit will be ab ble to discern between two or more results and priorittize the locatiions where it is needed thee most. Ou ur unit will be capable to naavigate its waay around the obstructions within its patth with precission and accurracy. In addittion, our remo ote units will be able to effficiently comppute the air deensity of the rroom and transm mit said resultt to the main unit.
Conclussion We W believe thaat the device will w have the highest efficiiency in remooving particlees from the inddoor environment. It will sig gnificantly reduce indoor air a pollution aand the ensuinng haze risk iif operated properly. The device will w be cost-efffective, not only o in purchaase, but also inn maintenancce (power, filtter change, ettc.). The mob bility of the deevice will red duce indoor haaze pollution in multiple roooms in the
Seenior Deesign Final Report ͟͠͞ ͟͢ house/apaartment setting. The most practical p use of o the purifierr will be to reeduce indoor ppollution in oone or two room ms only; most suitable, s pareents and childrren’s sleepingg rooms. The air purifier w will spend moost of the daytim me in rooms during d high ou utdoor pollutiion levels. Foor those livingg in an area w with high backgroun nd particle co oncentrations, as present in n most metroppolitan areas, this design w will be recommen nded to permaanently impro ove indoor qu uality.
Seenior Deesign Final Report ͟͠͞ ͟͢ Referen ces ● ● ● ●
htttp://home.ho owstuffworks..com/air-puriffier.htm htttp://www.oreeck.com/Orecck-AirInstinctt-200-AirPuriifier/544,defaault,pd.html?kkeycode=FH4476 htttps://www.aiirocide.com/ htttps://www.e epa.gov
