Indian Journal of Scinc and Tchnology, Vol 9(43), DOI: 10.17485/ijst/2016/v9i43/104393, Novmbr 2016 ISSN (Print) : 0974-6846 ISSN (Onlin) : 0974-5645 Modlling and Simulation of Objct Dtction in Automotiv Powr Window R. Kumar 1*, N.J. Ahuja 2, M. Saxna 3 and A. Kumar 1 1 Dpartmnt of Elctronics, Instrumntation and Control Enginring Univrsity of Ptrolum and Enrgy Studis, Dhradun-248001, Uttarakhand, India 2 Cntr of Information Tchnology, Univrsity of Ptrolum and Enrgy Studis, Dhradun - 248001, Uttarakhand, India 3 Dpartmnt of Mchanical Enginring, Univrsity of Tchnology and Managmnt, Shillong - 793001, Mghalaya, India Abstract Th papr focuss on th systm modlling of hardwar basd powr window control systm. In powr window systm, Dirct Currnt (DC) motor srvd as th sourc of powr to driv th powr window fram and accordingly powr window can b raisd and lowrd. In th papr, mathmatical modl of a DC motor controlld by an H bridg circuit and bridg is controlld through input switchs which ar availabl at drivr and passngr door sid. Th main objctiv of powr window control is to control th movmnt of glass door in uppr and lowr dirction and this opration is controlld with th hlp of currnt snsor, fir snsor and position snsor in th rplacmnt of manual control hand turnd crank tchniqus for xisting powr windows. Th driving componnt is DC motor that drivs th powr window using slflocking tchniqus for worm gar in th minimum ratio of 1:50 and output of worm gar gos to lad scrw having pitch of 3mm to dlivr linar movmnt to powr window. Th control unit of powr window snss both high and low load obstructions. It is usd to activat and dactivat th movmnt of th glass door in upward dirction and downward dirction with th hlp of DC motor, whnvr, any hard and soft obstruction is dtctd. Th automatic powr window with intllignt control is dsignd and vrifid with svral conditions that claim its movmnt in upward and downward dirction. Th simulation modl is visualizd in MATLAB/Simulink and prformanc is analysd with rspct to currnt, voltag and spd masurmnt. Kywords: DC Motor, Intllignt Window Control Systm., Mathmatical Modlling, Powr Window 1. Introduction Th powr window systm consists of motor that rotats in clockwis and countr clockwis dirction and accordingly window is raisd and lowrd which is controlld by mans of an array of switchs. Th window complts a driv circuit, whn th switch is activatd and snds th currnt to th motor to mov th window up or down. Powr window systms ar usd in automobils and should mt th safty standards and scurity vhicular opration to prvnt mor fatal and injurious accidnts lik pt nck as wll human body bing trappd, that can lad to suffocation bcaus of malfunction or usag rror of th powr window 1,6. In som of th dsign of vhicl powr window has th switch on a hand rst from whr it can b triggrd accidntally such as child can climb to plac his or hr had outsid of th window. Th drivr controlld lockout systm xists in som vhicls to ovrcom such problms. Such systm protcts th human and prvnts rar sat passngrs to mt accidnts by th triggr mchanism of th switch 6,9. Th lifting mchanism is a dvic that *Author for corrspondnc
Modlling and Simulation of Objct Dtction in Automotiv Powr Window plays significant rol in powr window systm. Th procss through which lifting windows in most cars happns du to a linkag to mov th window glass in upward dirction. Th DC lctric motor is associatd with th worm gar having ratio of 1:50 and diffrnt othr pinion gars to crat a larg gar rduction, aftr this it is connctd with lad scrw giving it appropriat torqu to lift th powr window. Th main advantag of worm gars mchanism is that it has th slflocking advancmnt fatur du to that it maks th angl of contact btwn th pinion gar and worm as shown in Figur 1. Th control systm is having drivr up, drivr down, passngr up, passngr down, tmpratur snsor and currnt snsor as input which ar procssd by th control systm and powr window dc motor is handling th load to adjust th mchanical movmnt in th automobils 1. Figur 1. Th basic structur of powr window control. Powr window lctrical control systm is of four typs. Thy ar classifid as Rlay drivn DC motor, H- Bridg drivn DC motor, Brush Lss DC motor (BLDC) and Prmannt Magnt Synchronous Motor (PMSM). Th Advantags ovr diffrnt powr window lctrical control tchniqus ar spcifid in Tabl 1. Tabl 1. Advantags ovr diffrnt powr window lctrical control tchniqus Control Advantag Tchniqus Rlay drivn DC motor H- Bridg drivn DC motor Brushlss DC motor Prmannt magnt synchronous motor Low Cost Lss powr dissipation Simpl to control using circuit dsign PWM spd rgulation No mchanical componnt No rlay nois High Efficincy Lss Nois Mor rliabl at high spd 10,000 r.p.m High Spd & Prcis High Efficincy High Torqu Th papr is organizd as follows: Sction1 rprsnts introduction, sction 2 prsnts systm modlling with physical systm dsign and MATLAB Simulink modl 7,8 to support th window sction modlling and its automation. Sction 3 prsnts th MATLAB simulation rsults and dscription to support th rsult outcom. In sction 4, th conclusion is prsntd. 2. Systm Modlling Th modl of th systm is prsntd with th hlp of mathmatical modl. 2.1 Physical Modlling A common actuator in powr window control systms is th DC motor 3. It dirctly provids rotary motion and, coupld with worm gar and lad scrw, can provid translational motion. Th lctric circuit of th armatur and fild ar shown in th blow Figur 2. Th input to th physical modl of powr window systm is th voltag applid to th motor s armatur coil, whil th output is th rotational movmnt of th shaft Rvolutions Pr Minut (RPM). Figur 2. systm 3. Circuit of physical modl of powr window In th dc motor, th magntic flux is inducd du to th inducing xisting in th stator. Th magntic fild gnratd by th coils is B. Th rotor is rotatd with rspct to th stator. Th supply givn to th stator hlps to rotat th rotor and can b vary with th incrmnt in numbr of coils. In th modlling it is assumd that singl coil is usd having inductanc L and Rsistanc R bcaus of disprsion in conductor. Th voltag quation in th sam circuit is givn by quation 1. ν t ()= L di + Ri (1) dt Th Laplac domain rprsntation of th quation 1 is givn by quation 2. 2 Vol 9 (43) Novmbr 2016 www.indjst.org Indian Journal of Scinc and Tchnology
R. Kumar, N.J. Ahuja, M. Saxna and A. Kumar i ( s) ν s k ( ) = 1+ τ s Hr k = 1 L is stator gain and τ = is stator tim R R constant Th stator is charactrizd with singl coil having inductanc La and Rsistanc Ra. Whn th back.m.f of th motor is considrd th quation of armatur is givn by quation 3. v t L di a a()= a + Ri a a+ (3) dt Th Laplacian transform of th quation 3 is givn by quation 4. ia ( s) ka ν s s 1 τ s (4) a ( ) ( ) = + Th Torqu xtractd by th motor is givn as T = K ƒ ƒ i M a Th EMF hold by th motor is givn as a = K ƒ ƒ ω (6) Th torqu and back mf of armatur winding is givn TM = Kii a (7) = Ki ω (8) Th motor xprincs th torqu whn th voltag is supplid to th stator and on th rotor. Th torqu is applid on th mchanical structur of th systm which dpnds on th viscous friction factor F and rotor momnt of inrtia J. It has also bn xprincd that th load torqu is analysd on th motor in ach oprational conditions of th motor. Equation 9 supports th sam functionality. T T J d ω M L = + Fω (9) dt In th quation 9 T L is load torqu and T M is motor torqu Th quation 9 in s domain is prsntd by quation 10. T s T s M ω( s) ( ) ( ) = + L (2) (5) Km ( 1 τ s) (10) Hr, K m = 1 F is th mchanical gain and τ m mchanical tim constant. m J = is th F 2.2 Simulation Modl Th simulation modl prsnts th powr window systm basd motor drivn mchanism. Th DC motor is driving th powr window mchanism having slf-locking worm gar with th ratio 1: 50. Th output of worm gar gos to lad scrw having pitch of 3 mm to dlivr linar movmnt to powr window. Th powr window control mchanism and its modl us th driving pully i.. DP, four supporting rollrs RL1, RL2, RL3, and RL4, and two clamping glasss, GCL1 and GCL2. Th clamping glasss ar attachd to th powr windows which hav th movmnt to lift th window in up dirction. Th clamping glasss GC1 and GC2 ar also attachd with th rop in such mannr that both clamps GC1 and GC2 can mov forward following th sam vlocity. It hlps th window to kp window lvl in th straight. MATLAB Simulink platform provids th pully driving simulation with th hlp of Rop Drum block. Morovr, in th sam way th supporting rollrs ar modlld using th blocks rlating to Blt Driv Pully. Th spcification and dscription of powr window controllr using Simulink is listd in Tabl 2. Th controllr must dtrmin th powr window movmnt on th basis of diffrnt input valus and spcifid systm rquirmnts. Th up and down movmnt of th powr window is don through controllr and dpnds on drivr up and down switch, passngr up and down switch, motor armatur currnt and tmpratur snsor 5. Th drivr up and down switch and passngr up and down switch is digital switch whras motor armatur currnt and tmpratur snsor ar analog snsors. According to ths data controllr dtrmin whthr th powr window will mov upward and downward accordingly. Tabl 2. Physical paramtrs for our simulation modl S.No Paramtrs Valu 1. Rotor momnt of 3.2284E-6 kg.m 2 inrtia 2. Viscous friction 3.5077E-6 Nms constant of motor 3. Forcing constant 0.0274 V/rad/sc ( EMF) 4. Torqu constant of DC 0.0274 Nm/Amp Motor 5. Valu of rsistanc 4 ohm 6. Valu of inductanc 2.75E-6H 7. Rotor Damping 1-06 Vol 9 (43) Novmbr 2016 www.indjst.org Indian Journal of Scinc and Tchnology 3
Modlling and Simulation of Objct Dtction in Automotiv Powr Window 2.3 Controllr Dsign Th sction provids information to th switch basd controllr implmntd in MATLAB Simulink. Th controllr structur is considrd basd on th control inputs shown in Figur1. In controllr, according to following inputs motor forward and rvrs movmnt is achivd. 1 st Input: Drivr powr window switch prssd Upward. 2 nd Input: Drivr powr window switch prssd Downward. 3 rd Input: Passngr powr window switch prssd Upward. 4 th Input: Passngr powr window switch prssd Downward. 5 th input: Tmpratur input. 6 th Input: Currnt snsor. According to abov inputs controllr dcids whthr th powr window will mov in upward dirction or downward dirction or will not mov. Figur 3. MATLAB Simulink modl for simulation of powr window control. Th modlling languag Simulink is dvlopd to mt th nds of diffrnt multi domain systm lik lctrical systm, Mchanical systm and control systm. According to th torqu, spd and obstacl bhaviour DC motor for powr window is controlld, th ovrall powr window and motor modl wr built using Matlab/Simulink. Th Upward switch, downward switch and obstacl dtrmind th movmnt of powr window motor. At first usr should provid appropriat input to controllr, and thn modify th controlling tchniqus. Th suggstd modl computs th ral tim load currnt that follow th powr window dynamics quations. In th sam way, it can b stimatd that th load voltag is also following sam dynamic quations. Th simulation systm modl wr built using Matlab/Simulink and shown in blow Figur 3. 2.3.1 Obstacl Dtction Dsign In this powr window modl, th systm continuously monitors th load on th motor shaft to dtct prsnc of obstacl 2. Whn th powr window rcognizs an obstacl, th applid load forc on th powr window shaft incrass th load on th motor and consquntly riss in armatur currnt. With incras in armatur currnt in powr window motor with appropriat currnt snsor in sris with DC motor dtcts obstacl in th powr window path. 3. Rsults and Discussions Th impact of currnt, voltag and motor spd of th powr window systm simulation modl is blow with th hlp of F Figur 5,6 and 7 rspctivly. 3.1 Currnt Masurmnt Figur 4. window. Simulation of currnt vrsus tim (t) of powr 4 Vol 9 (43) Novmbr 2016 www.indjst.org Indian Journal of Scinc and Tchnology
R. Kumar, N.J. Ahuja, M. Saxna and A. Kumar 3.2 Voltag Masurmnt Figur 5. window. Simulation of voltag vrsus tim (t) of powr 3.3 Spd (RPM) Masurmnt Figur 6. Simulation of motor spd (RPM) of motor vrsus tim (t) of powr window. It is clar from th simulation modl shown in Figur 4, that th window is moving upward and downward with objct dtction. In th simulation wavform th upward and downward currnts ar 5.7 Amp and - 4.8 amp rspctivly. Th simulation rsult in Figur 5 shows that th voltag is varying form -12 V to +12 V which is constant for th ntir duration. Th simulation rsult in Figur 6 shows that th motor spd 1550 RPM in upward motion and 2550 in downward motion. Currnt, voltag and RPM of th motor hav significant impact. It is bcaus of powr window control algorithm incorporatd with th physical modl spcially if th rsults ar obsrvd using convntional powr window stop mchanism lik Hall snsor mthod or angular vlocity mthod. Th prformancs of th currnt snsor basd powr window systm hav bttr prformanc. Th powr window DC motor currnt gradually riss to significant thrshold valu and th powr window automatically wnt downward with an optimal distanc, whn powr window touchs th obstacl 10. 4. Conclusions In th rsarch articl, th modlling and simulation of automotiv powr window systm using MATLAB Simulink tool. In th powr window systms modl, lctrical and mchanical systm clubbd togthr and simulation modl wr dvlopd and using torqu coupld sub modls to connct two diffrnt simulation modls, thos lmnts composd of a mix of lctrical, lctronic and mchanical systm modl. Th simulation modl prsntd in th rsarch papr is a MATLAB/Simulink basd systm that nhancs th safty and comfort with rspct to powr window. Th automobil vhicls ar nhancing day by day and Engin Control Unit (ECUs) is on th major part of automobil. Th proposd automatic window will b grat xtnt solution to th automobil industris to nhanc its fficincy and fastr rspons tim armatur currnt snsor and tmpratur snsors. Th hardwar implmntation of th simulatd modl dfinitly will incras th safty of th systm. Furthr th rsarch can b carrid out to implmnt th sam systm in harsh conditions including lctromagntic intrfrnc, diffrnt typs of noiss, and compatibility. In appropriat stimations of th DC motor, holding torqu ffct and frictional ffct must b includd in th simulation modl. 5. Conflicts of Intrsts Th authors dclar that no conflicts of intrst ar xisting rgarding th publication of this rsarch papr. 6. Rfrncs 1. Park JH, Choi GH, Yoon TS Park JB. A Snsorlss Safty Powr Window Control Systm in Automotiv Application. Intrnational Confrnc on Control, Automation and Systms,COEX, Soul, Kora. 2008. P.1457 61. 2. Liu Xiaoming, Shao Yahui, Wu Haowi, Zhong Yuanhong. Dsign of Car Window Anti-trapping Without Snsor. Micromotors Srvo Tchniqu. 2007;(4):48 9. 3. Luca Zaccarin. DC motors: Dynamic Modl and Control Tchniqus. Lctur givn 2012. 4. Ehsani M, Rahman M,Toliyat H. Propulsion Systm Dsign of Elctric and Hybrid Vhicls. IEEE Transactions on Industrial Elctronics. 1997 Fb; 44(1). Vol 9 (43) Novmbr 2016 www.indjst.org Indian Journal of Scinc and Tchnology 5
Modlling and Simulation of Objct Dtction in Automotiv Powr Window 5. Kumar R, Krogh BH. Htrognous Vrification of Embddd Control Systms. Procdings of th 2006 Amrican Control Confrnc Minnapolis, Minnsota, USA. 2006 Jun 14-16. p. 4597 62. 6. Kumar R, Kumar A. Dsign and hardwar dvlopmnt of powr window control mchanism using microcontrollr. Intrnational Confrnc on Signal Procssing and Communication. IEEE Xplorr, pp(361 365) 7. Karris ST. Introduction to Simulink with Enginring Applications. Orchard Publications, unitd statpublication 2006. 8. Tiwari T, Shah A, Nainwad CS.Dsign and dvlopmnt of high powr window for linar acclrator at 2.856 GHz3rd IEEE Intrnational Vacuum Elctronics Confrnc(IVEC). 2002. P.377 8. 9. Wang Yi, Qiu Yunfng, Yin Ji. Application of automobil powr window controllr for priphral intrfac controllr.intrnational Confrnc on Elctronic Masurmnt and Instrumnts (ICEMI), IEEE; Aug 2011.2, p.363 7. 10. Prawoto Y, Yusof MA. Automotiv powr window Mchanism failur initiatd by ovrload. Enginring Failur Analysis.2013 July; 179 88. 6 Vol 9 (43) Novmbr 2016 www.indjst.org Indian Journal of Scinc and Tchnology