sim motion understandingmotion wp eng

7/27/2019 SIM Motion UnderstandingMotion WP ENG

1/17

Uestai Mti Simuati

SUMMARY

What is mti simuati? What ems ca it sve? Hw ca it

eeft the uct esi cess? This ae aesses sme

these issues a s at same ems that mti simuati ca

sve. It as esets ea-ie aicatis mti simuati use

as a CAE esi t.

w h i t e p A p


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inroducon

Sice the 1980s, whe compute-aided egieeig (CAE) methods st

became avaiabe i desig egieeig, ite eemet aaysis (FEA) becam

the st widey adopted simuatio too. Ove the yeas, it has heped desig

egiees study the stuctua peomace o ew poducts, ad epace ma

time-cosumig, costy pototypes with iexpesive compute simuatios uo CAD modes.

Today, because o the gowig compexity o mechaica poducts ad icea

igy ece competitio to big ew desigs to maket aste, egiees ee

moutig pessue to exted the scope o simuatio beyod FEA. Aog wit

simuatig stuctua peomace with FEA, egiees aso eed to detemi

the kiematics ad dyamics o ew poducts beoe the buidig o physica

pototypes.

Motio simuatioaso kow as igid body dyamicsoes a simuatio

appoach to sovig those issues. Its use is gowig ast, ad as it does, desig

egiees wat to kow moe about it, askig: What it is? What pobems cait sove? How ca it beet the poduct desig pocess?

Moon smulaon for mcansm analyss and synss

Suppose a egiee is desigig a eiptic tamme meat o tacig die

et eipses. Whe he has deed mates i the CAD assemby, he ca aima

the mode to eview how the compoets o the mechaism move (Figue 1)

Athough assemby aimatio ca show the eative motio o assemby com

ets, the speed o motio is ieevat ad timig is abitay. To d veociti

acceeatios, joit eactios, powe equiemets, etc., the desige eeds a

moe poweu too. This is whee motio simuatio comes i.

FigURe 1: VArIoUS poSITIonS o EllIpTIC TrAMMEl SIMUlATEd USIng

CAd AnIMATor

Motio simuatio povides compete, quatitative iomatio about the

kiematicsicudig positio, veocity, ad acceeatio, ad the dyamics

icudig joit eactios, ietia oces, ad powe equiemets, o a the

compoets o a movig mechaism. Ote o geat additioa impotace,

the esuts o motio simuatio ca be obtaied vituay at o additioa time

expese, because eveythig eeded to peom motio simuatio has bee

deed i the CAD assemby mode aeady, ad just eeds to be taseed

the motio simuatio pogam.

U n D E r S T A n D I n g M O T I O n S I M U l A T I O n

Motio simuatio povides com-

pete, quatitative iomatio aboutthe kiematicsicudig positio,veocity, ad acceeatio, ad the

dyamicsicudig joit eactios,ietia oces, ad powe equie-

mets, o a the compoets o amovig mechaism.


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I the case o the eiptic tamme descibed above, the desige eeds oy t

decide the speed o the moto, the poits to be taced, ad the motio esut

he wishes to see. The pogam does eveythig ese automaticay, without th

uses itevetio. The motio simuatio pogam uses mateia popeties

om the CAD pats to dee ietia popeties o mechaism compoets, a

tasates CAD assemby matig coditios ito kiematic joits. It the auto

maticay omuates equatios that descibe the mechaism motio.

Uike fexibe stuctues studied with FEA, mechaisms ae epeseted as

assembies o igid compoets ad have ew degees o eedom. A umei

ca sove soves the equatios o motio vey quicky, ad esuts icude u

iomatio about dispacemets, veocities, acceeatios, joit eactios, ad

ietia oads o a the mechaism compoets, as we as the powe ecess

to sustai the motio (Figue 2).

FigURe 2: lInEAr VEloCITy And MoTor poWEr rEqUIrEMEnT CAlCUlATEd

by MoTIon SIMUlATor

A simuatio o the motio o the iveted side mechaism show i

Figue 3 pesets a execise commoy oud i textbooks o the kiemat

o machies. Hee, the objective is to d the agua speed ad the accee

atio o the ockig am, whie the cak otates at a costat speed. Seve

aaytica methods ca sove the pobem, ad the compex umbes metho

is pehaps the most equety used by studets. Howeve, sovig such a

pobem by had equies itesive cacuatios, ad eve with the hep o

computeized speadsheets, it may take a ew hous to costuct veocity

ad acceeatio pots. The, i the geomety o the side chages, the who

thig has to be epeatedmakig this a iteestig assigmet o ude-

gaduate studets but competey impactica i ea ie poduct deveopme

Motio simuatio sotwae makes it possibe to simuate the motio o theiveted side pacticay istaty, usig data aeady peset i the CAD

assemby mode.


The motio simuatio pogam uses

mateia popeties om the CADpats to deie ietia popetieso the mechaism compoets, ad

tasates CAD assemby matigcoditios ito kiematic joits.


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FigURe 3: SIMUlATIon o An InVErTEd SlIdEr MECHAnISM To CAlCUlATE

AngUlAr VEloCITy o roCkIng ArM

Motio simuatio aso checks o iteeeces, ad this is a vey dieet p

cess om the iteeece checkig avaiabe with CAD assemby aimatio.

Motio simuatio coducts iteeece checks i ea time, ad povides the

exact spatia ad time positios o a mechaism compoets as we as theexact iteeig voumes. Eve moe, whe the geomety chages, as show

the quick etu mechaism i Figue 4, the sotwae updates a esuts i se

ods. Each ad evey esut petaiig to motio may be peseted gaphica

o tabuated i ay desied omat.

FigURe 4: USErS CAn EASIly dETECT And CorrECT InTErErEnCE bETWEE

SlIdEr And drIVEn lInk.

Egiees ca epeset simpe mechaisms such as the eiptic tamme o

iveted side descibed above as 2D mechaisms. Athough these ae di-

cut ad time-cosumig to aayze by had, they do posses aaytica sou-tio methods. Howeve, 3D mechaisms, eve simpe mechaisms such as

that show i Figue 5, have o estabished method o aaytica soutio.

But motio simuatio ca sove the pobem easiy i secods, because it is

desiged to hade mechaisms o ay ad evey compexity, both 2D ad 3

The mechaism may cotai a age umbe o igid iks, spigs, dampes,

ad cotact pais with vituay o peaty i soutio time. Fo exampe, the

motios o the ot-ed suspesio o the sowmobie i Figue 6, execise

machie i Figue 7, o CD dive i Figue 8, may be simuated with the same

ease as that o the iveted side.

Motio simuatio coducts ite-

eece checks i ea time, adpovides the exact spatia ad time

positios o a mechaism compo-ets as we as the exact itee-ig voumes.



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FigURe 5: A SIMplE 3d MECHAnISM IS VEry dIICUlT To AnAlyzE by HAnd

bUT prESEnTS no problEMS or MoTIon SIMUlATIon.

FigURe 6: A ronT-End SUSpEnSIon o A SnoWMobIlE ConSISTS o

nUMEroUS lInkS InClUdIng SprIngS And dAMpErS.

FigURe 7: An ExErCISE MACHInE dESIgn bEnEITS roM MoTIon SIMUlATI

USEd To opTIMIzE THE STEpS MoTIon TrAjECTorIES And CAlCUlATE THE

poWEr gEnErATEd by THE USEr.

FigURe 8:A Cd drIVE IS A CoMplEx MECHAnISM, yET EASIly AnAlyzEd byMoTIon SIMUlATIon.

I additio to mechaism aaysis, poduct deveopes ca aso use motio

simuatio o mechaism sythesis by covetig tajectoies o motio ito

CAD geomety, ad usig it to ceate a ew pat geomety. Figue 9 shows a

sampe pobem. This desig eatues a cam that shoud move a side aog

a guide ai, ad uses motio simuatio to geeate a poe o that cam. The

use expesses the desied side positio as a uctio o time ad taces th

side movemet o the otatig bak cam (the oud pate). The he cove

the tace path ito CAD geomety to ceate the cam poe show i Figue

I additio to mechaism aaysis,

poduct deveopes ca aso usemotio simuatio o mechaism

sythesis by covetig tajectoieso motio ito CAD geomety.



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FigURe 9: A dISplACEMEnT UnCTIon IS ApplIEd To MAkE THE SlIdEr TrAV

Along THE gUIdE rAIl.

FigURe 10: TrAVEl o THE SlIdEr IS TrACEd on THE roTATIng roUnd plATE

CrEATE A CAM proIlE, IllUSTrATEd HErE WITH A grooVE CUT In THE plATE

Desiges ca aso use tajectoies o motio, o exampe, to veiy the motio

o a idustia obot, such as that show i Figue 11, ad test the toopath

obtai iomatio ecessay whe seectig the size o obot eeded, ad to

estabish powe equiemetsa without the eed o ay physica tests.

FigURe 11: SIMUlATEd MoVEMEnT o An IndUSTrIAl roboT THroUgH SEV

ErAl poSITIonS MAkES IT poSSIblE To CrEATE A ToolpATH WITHoUT Any

pHySICAl TESTS.

Aothe impotat appicatio o motio simuatio eates to motio iduced

by coisios betwee movig bodies. Eve though cetai assumptios must

made about the easticity o such impactig bodies, motio simuatio poduc

accuate esuts o mechaisms with compoets that may expeiece oy

tempoay cotact, as show i Figue 12.

Desiges ca aso use tajectoies

o motio to veiy the motio o aidustia obot.



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FigURe 12: IMpACT And ConTACT CAn bE SIMUlATEd In MoTIon SIMUlATIo

or ExAMplE, To STUdy A gAp THAT MAy orM bETWEEn A CAM And A o

loWEr (roCkEr) In A VAlVE lITIng MECHAnISM.

Usn moon smulaon alon FeA

To udestad how motio simuatio ad FEA wok togethe i mechaism

simuatio, it heps to udestad the udameta assumptios o which eac

too is based.

FEA is a umeica techique o stuctua aaysis that has come to be the

domiat CAE appoach o studyig stuctues. It ca aayze the behavio o

ay my suppoted eastic object, such as the backet show i Figue 13. B

eastic we mea the object is deomabe. With the appicatio o a static oad

the backet acquies a ew, deomed shape, ad the emais motioess. T

appicatio o a dyamic oad causes the backet to vibate about the positio

o equiibium. FEA ca study dispacemets, stais, stesses, ad vibatio o

the backet ude static o dyamic oad.

FigURe 13: A IrMly SUpporTEd brACkET CAnT MoVE WITHoUT dEorMA-

TIon.

I cotast, a patiay suppoted object, such as the fywhee higed o the

backet (Figue 14) ca otate without havig to deom. The fywhee ca m

as a igid body, which cassies the device as a mechaism athe tha as a

stuctue. To study the motio o the fywhee, we use motio simuatio. Sta

ad stesses caot be cacuated whe teatig the fywhee as a igid body

(Fo moe iomatio, pease see Appedix 1.)

To udestad how motio simuatio

ad FEA wok togethe i mechaismsimuatio, it heps to udestad the

udameta assumptios o whicheach too is based.



8/17

FigURe 14: A lyWHEEl SpInS AS A rIgId body AboUT THE HIngE joInIng

To THE bASE (Top). THE prESEnCE o rIgId body MoTIon (boTToM) ClAS

IES THIS dEVICE AS A MECHAnISM.

The dieece betwee a stuctue ad a mechaism may ot be obvious at

st sight, as the two devices i Figue 15 iustate. Both have swig amscoected to a immovabe base by a hige. The oe o the ight has a spi

coectig the am to the base. The device without the spig is the mecha-

ism, because the swig am ca otate eey. Whethe it spis about the

hige o osciates about the positio o equiibium, o pat o the device has

deom duig the am movemet. The am shows igid body motio, cassiy-

ig the device o the et as a mechaism. Desiges ca study its motio wi

motio simuatio.

FigURe 15: THE SWIng ArM on THE lET CAn MoVE WITHoUT dEorMATIo

THUS ITS A MECHAnISM. Any MoVEMEnT In THE ArM on THE rIgHT IS ACCo

pAnIEd by dEorMATIon o THE SprIng; THIS MEAnS ITS A STrUCTUrE.

The additio o the spig chages the atue o the device, because ow th

am caot move without deomig the spig. The oy possibe om o cotiuous am motio is vibatio about the positio o equiibium. Deomatio

the spig accompaies am motio ad this cassies the device o the igh

as a stuctue. FEA ca aayze the am vibatio, ad, i desied, ca go o to

cacuate stais ad stesses i the spig ad i othe compoets which a

teated as eastic bodies. (Pease see Appedix 2 o uthe iomatio abo

the dieeces betwee motio simuatio ad FEA.)


The dieece betwee a stuctue

ad a mechaism may ot be obvi-ous at ist sight.


9/17U n D E r S T A n D I n g M O T I O n S I M U l A T I O n

I, havig competed motio simuatio studies, the desig egiee wats to

peom deomatio ad/o stess aaysis o ay mechaism compoet, t

chose compoet eeds to be peseted to FEA o stuctua aaysis.

Motio simuatio esuts suppy the iput data, cosistig o joit eactios a

ietia oces that act upo each ik o the mechaism, equied o stuctu

aaysis coducted with FEA. Motio simuatio aways cacuates these actowhethe o ot oowed by FEA. Joit eactios ad ietia oces ae, by de

itio, i baace, ad mechaism compoets subjected to a baaced set o

oads ca be submitted to FEA ad teated by the aaysis pogam as i they

wee stuctues.

Whie the egiee ca tase that data om motio simuatio to FEA ma

ay, he ca be sue o the best esuts i the motio simuatio sotwae ca

expot esuts to FEA automaticay. Whe used i such a way, motio simu-

atio ad FEA peom whats temed couped simuatio. This oes the

advatage o deig FEA oads automaticay, eimiatig guesswok ad po

sibe eos commo to maua setup.

The exampe o a cak mechaism pobem show i Figue 16 demostat

the couped simuatio. Hee, the desig egiee wats to d the maximum

stesses i the coectig od.

FigURe 16: MoTIon SIMUlATIon IndS rEACTIonS on boTH EndS o THE Co

nECTIng rod. InErTIAl orCES ACTIng on THE rod ArE AlSo CAlCUlATEd

The pocedue o combiig the use o motio simuatio ad FEA is:1. Use motio simuatio to d dispacemets, veocities, acceeatios, joi

eactios, ad ietia oces actig o a compoets withi the age o

motio seected o study. I this step, a the mechaism iks ae teate

as igid bodies. The pots i Figue 16 show coectig od joit eactio

duig oe u tu o a cak.

Couped simuatio oes the

advatage o deiig FEA oadsautomaticay, eimiatig guess-

wok ad possibe eos commoto maua setup.



2. Fid the mechaism positio that coespods to the highest eactio

oads o the joits o the coectig od. Aaysts most ote ook o t

highest eactios because the aaysis ude the maximum oads show

the maximum stesses expeieced by the coectig od. I desied,

howeve, ay umbe o positiossee Figue 17may be seected o

aaysis.

FigURe 17: orCESrEACTIonS on boTH EndS And InErTIAl orCES

ACTIng on THE ConnECTIng rod MAy bE dETErMInEd or Any nUMbEr

o CrAnk SHAT MECHAnISM poSITIonS.

3. Tase those eactio oads, aog with the ietia oad om the CAD

assemby, to the coectig-od CAD pat mode.

4. The oads that act o the coectig od isoated om assemby cosist

joit eactios ad ietia oces, as show i Figue 18. Accodig to th

dAambet picipe, these oads ae i baace, makig it possibe to te

the coectig od as a stuctue ude a static oad.

FigURe 18: ACCordIng To THE dAlAMbErT prInCIplE, joInT rEACTIonS A

In bAlAnCE WITH InErTIAl orCES.

5. A coectig od subjected to a baaced set o static oads is assiged

eastic mateia popeties ad submitted to FEA o stuctua static aa

sis. FEA peoms stuctua aaysis to d deomatios, stais, ad

stesses (Figue 19).

Aaysts most ote ook o the

highest eactios because the aay-sis ude the maximum oads shows

the maximum stesses expeieced.



FigURe 19: THE ConnECTIng rod IS prESEnTEd To EA AS A STrUCTUrE STHAT STrESSES CAn bE CAlCUlATEd.

Moon smulaon and s

Motio simuatio is capabe o impotig time-histoy data om a test. This w

a motio o a existig mechaism ca be easiy epoduced ad uy aayz

icudig a joit eactios, ietia eects, powe cosumptio, ad moe. us

iexpesive compute modes athe tha time-cosumig ad expesive tes

I a simia way a mechaism ca be aayzed ude iput deed by a aa

ytica uctio.

FigURe 20: TEST dATA or MoTIon o THE ConTrol ArM IS USEd AS An

InpUT To MoVE THE SUSpEnSIon ModEl In MoTIon SIMUlATIon.

Fo exampe, i the case o a ca suspesio, pictued i Figue 20, motio

simuatio aswes such typica questios as: How soo ate a whee hits

a cub wi the osciatio caused to the suspesio die out? What is the

equied dampig i the stut? What stesses ae iduced i the coto am

ad its bushigs?

inrad CAD, moon smulaon, and FeA

Both motio simuatio ad FEA use a CAD assemby mode as a peequisit

o aaysis. A commo, itegated eviomet o a thee toos aciitates

the data exchage amog CAD, motio simuatio, ad FEA. Itegatio avoi

cumbesome data tase via euta e omats, typica to stadaoe appi-

catios. I additio, the use o motio simuatio itegated with CAD, ad oiteaced with it, geaty educes the eot equied to set up motio simuat

modes.

As discussed above, mateia popeties ad CAD assemby mates ca be

e-used whe ceatig a motio simuatio mode. Motio tajectoies, which

ae esuts o motio simuatio, ca be tued back ito CAD geomety. This

howeve, is oy possibe i a itegated sotwae eviomet. Additioay,

Both motio simuatio ad FEA use

a CAD assemby mode as a peeq-uisite o aaysis.



itegatio with CAD eimiates a eed o maitaiig a database o motio

simuatio modes by stoig the simuatio mode data ad the esuts o sim

atios togethe with the CAD assemby mode. last but ot east, ay CAD

chages ae uy associative with motio simuatio as we as with FEA.

The SoidWoks CAD pogam togethe with SoidWoks Simuatio (FEA)

ad SoidWoks Motio (motio simuatio) as add-is epesets the state othe at i itegated simuatio toos. Fu itegatio has bee made possibe

because SoidWoks, SoidWoks Simuatio, ad SoidWoks Motio ae a

ative Widows appicatios. A wee deveoped specicay o the Widow

opeatig system ad ot just poted om othe opeatig systems. Fu com

patibiity with Widows aso assues compatibiity with othe appicatios u-

ig i Widows.

SoidWoks Simuatio, a eadig FEA pogam, has og pove itse vey va

abe as a poduct desig too wokig cosey with CAD, as show i Figue 2

The additio o SoidWoks Motio ow eabes a eve moe compete sim

tio o ew poducts, ad heps to educe the umbe o physica pototypes

eeded i poduct deveopmet (Figue 22).

FigURe 21: THIS dESIgn proCESS USES CAd And EA AS dESIgn ToolS.

FigURe 22: THE dESIgn proCESS bEnEITS roM USIng MoTIon SIMUlATIo

Along WITH CAd And EA.

The SoidWoks CAD pogam

togethe with SoidWoks Simua-tio (FEA) ad SoidWoks Motio

(motio simuatio) as add-isepesets the state o the at iitegated simuatio toos.

Soldworks

CAD

Soldworks

Smulaon

FeA

Soldworks Moon

Moon Smulaon

Soldworks

Smulaon

FeA

Soldworks

CAD



Ral-lf xamls

Tigercat

Tigecat (www.tigecat.com), a eadig mauactue o such oesty equipm

as skiddes, owades, ad ee-buches, used SoidWoks to desig the

ee-buche head show i Figue 23. The compays egiees the simu

ated its uctios with SoidWoks Motio ad SoidWoks Simuatio. Tigec

epots that simuatio o the motio, dyamics, ad stesses o this compex

mechaism educed empiica testig equiemets to a sige pototype.

Pototype testig uy comed the simuatio digs.

FigURe 23: THE EllIng HEAd o A EllEr-bUnCHEr by TIgErCAT, o

brAndord, onTArIo WAS dESIgnEd In SolIdWorkS And SIMUlATEd In

SolIdWorkS MoTIon And SolIdWorkS SIMUlATIon.

FANUC Robotics America Inc.

FAnUC robotics (www.aucobotics.com) mauactues a widey used obo

poduct ie that heps customes i may dieet idusties optimize abo,

owe costs, impove quaity, ad miimize waste i thei mauactuig opeatios. Fo its customes to gai those beets, FAnUC oes may dieet

sizes o obotic toos, as idicated i Figue 24, ad the customes eed to

seect the ight size o thei specic appicatios. They do so by aayzig ob

peomace aog specied toopathsad simuatio with SoidWoks Moti

makes such aaysis ad seectio much easie.

FigURe 24: THIS IndUSTrIAl roboT WAS CrEATEd by AnUC roboTICS

AMErICA, o roCHESTEr HIllS, MICHIgAn.

Simuatio o the motio, dyamics,

ad stesses o this compex mecha-ism educed empiica testig

equiemets to a sige pototype.



Ward Machine Tool

Wad Machie Too (www.wadcc.com) desigs ad mauactues custom

athe chucks o aumium whees, otay actuatos, ad speciaty machiig

xtues. Wads egiees desig custom poducts that have eve bee bui

beoe, ad d simuatio to be idispesabe o veiyig whethe o ot a

ew desig wi wokbeoe sedig it to be mauactued. Fo exampe, thcompay deveoped ad tested the dua-actuated/mutiage aumium whe

athe chuck show i Figue 25 without testig ay physica pototypes. Wad

epots that though the use o SoidWoks ad SoidWoks Motio, it eaized

a estimated $45,000 i cost savigs, ad educed testig time to just 10 pe

cet o its ome buid-ad-test pocess.

FigURe 25: WArd MACHInE Tool o oWlErVIllE, MICHIgAn dESIgnEd An

SIMUlATEd THE lATHE CHUCk.

Syncroness

Sycoess (www.sycoess.com) is a poduct deveopmet bueau that wo

cosey with customes to deveop poducts that vay om execise equipmeto ase systems. Sychoess used both SoidWoks Motio ad SoidWoks

Simuatio to optimize the ou-ba ikage system o a scissos it show

i Figue 26. Accodig to Sycoess, the egieeig team coducted the

motio simuatio with itte taiig ad o dow time. Sycoess says that

the use o simuatio made it possibe to coduct quick desig iteatios, ad

povided a geat visuaizatio too o the customeso that ovea, it was vita

to the successu desig soutio.

FigURe 26: THIS lITIng plATorM WAS dESIgnEd by SynCronESS,

o WESTMInSTEr, ColorAdo USIng SolIdWorkS, SolIdWorkS MoTIon,

And SolIdWorkS SIMUlATIon AS dESIgn ToolS.

Though the use o SoidWoks ad

SoidWoks Motio, it eaized aestimated $45,000 i cost savigs,

ad educed testig time to just10 pecet o its ome buid-ad-test pocess.



AppeNDiX 1: Rd Body Moon

I a object ca move without udegoig deomatio, we descibe it as hav-

ig igid body motio, o igid body mode. The pesece o igid body motio(

cassies the object as a mechaism.

Figue 27 shows a ba joit. The base is immovabe. Such a joit has thee

body motios because it ca move i thee idepedet diectios, o thee

otatios, without deomatio. Thee idepedet vaiabes, aso caed dege

o eedom, descibe the positio o this mechaism.

FigURe 27: THE bAll joInT MECHAnISM SHoWn IS A kInEMATIC pAIr WITH

THrEE rIgId body MoTIonS.

Figue 28 iustates a pate sidig o a immovabe base pate. This mecha-

ism aso has thee igid body motios because the sidig pate ca tasat

i two diectios ad ca otate i oe diectio without expeiecig ay

deomatio. Agai, thee degees o eedom descibe the positio o the

mechaism.

FigURe 28: THE SlIdIng plATE MECHAnISM HAS THrEE rIgId body MoTIon

The ou-ba ikage show i Figue 29 has oe igid body motio. Oe ide

pedet vaiabe, o exampe the agua positio o ay ik, descibes the

positio o the etie mechaism. note that depedig o the detaied hige

desig, hige pis may have oca igid body motios, that is, otatio about thpi axis ad/o sidig aog the pi axis.

The pesece o igid body motio(s)

cassies the object as a mechaism.


16/17

FigURe 29: AngUlAr poSITIon o Any lInk In THE MECHAnISM dEInES

THE poSITIon o THE EnTIrE MECHAnISM. THIS MECHAnISM HAS onE rIgId

body MoTIon.

A thee o the iustated mechaisms may aso have degees o eedom du

to motio that esuts om deomatio. These ae caed eastic modes. I t

ou-ba ikage, o exampe, each idividua ik may peom a motio whie

aso expeiecig vibatio. Modes o vibatio equie aaysis with FEA aththa with motio simuatio.

AppeNDiX 2: Comarson of Moon Smulaon and FeA

Motio simuatio ad FEA compemet each othe, ad thei teitoies may

oveap, as ca be see i the tabe beow:

ty of problm FeA Moon Smulaon

Aaysis o stuctues (deomabe objects) Yes no*

Aaysis o mechaisms no Yes

Aaysis o deomatios ad stesses Yes no

Aaysis o vibatio Yes no**

Aaysis o modes with igid body motios no*** Yes

Aayzed mode must be meshed Yes no

Aayzed mode is pepaed i CAD Yes Yes

* Motio simuatio does aow o some deomabe compoets, such as spigs ad fexibe joits. I the aaysis studies mo

ivovig impact, the use dees the easticity o coidig bodies.

** Motio simuatio sotwae ca aayze vibatio, i the mode icudes eastic compoets such as spigs. Such vibatio

aaysis is imited to osciatio due to deomatio o those eastic compoets, whie othe mechaism compoets (iks)

emai igid.

*** With specia modeig techiques, such as the additio o sot spigs o ietia eie to the FEA mode, igid bod

motios may be eimiated aticiay so that FEA ca aayze stuctues with igid body motios.


Modes o vibatio equie aaysis

with FEA athe tha with motiosimuatio.


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Concluson

Aog with simuatig stuctua peomace with FEA, egiees eed to

detemie the kiematics ad dyamics o ew poducts beoe the buidig

physica pototypes. They aso ace moutig pessue to exted the scope o

simuatio beyod FEA. Motio simuatio oes a simuatio appoach to so

ig these pobems. The esuts o motio simuatio ca be obtaied vituaat o additioa time expese, because eveythig eeded to peom motio

simuatio has bee deed i the CAD assemby mode aeady.

I additio to mechaism aaysis, poduct deveopes ca aso use motio

simuatio o mechaism sythesis by covetig tajectoies o motio ito

CAD geomety, ad usig it to ceate a ew pat geomety. I, havig compet

motio simuatio studies, the desig egiee wats to peom deomatio

ad/o stess aaysis o ay mechaism compoet, the chose compoe

eeds to be peseted to FEA o stuctua aaysis. Motio simuatio esu

suppy the iput data equied o stuctua aaysis coducted with FEA.

Whie the egiee ca tase that data om motio simuatio to FEA maay, you ca be sue o the best esuts i the motio simuatio sotwae ca

expot esuts to FEA automaticay. SoidWoks sotwae oes just such a

capabiity with its uy itegated SoidWoks Simuatio ad SoidWoks Mot

sotwae. Togethe, these SoidWoks soutios eabe a eve moe compe

simuatio o ew poducts ad hep educe the umbe o pototypes equi

sim motion understandingmotion wp eng

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