DESIGN AND FABRICAT FABRICATION ION OF A SCALED CNC MILLING MACHINE
BY
Adnan Moiz – 2012-024 Faizan Taimoor Saqib – 2012-101 Muhammad Annas Zakir – 2012-199 Muhammad Muhammad Zarrar Shakeel – 2012-279
Advisor:
ro!essor "r# $asim A# %han
Submi&&ed in 'ar&ial !ul!illmen& o! &he requiremen&s !or &he de(ree o! )a*helor o! S*ien*e
Faculty o M!c"a#ical E#$i#!!ri#$ GI% I#stitut! o E#$i#!!ri#$ Sci!#c!s & T!c"#olo$y' T!c"#olo$y' To(i' %)*
A(ril +,-.
ABSTRACT
This re'or& aims &o e+'lore e+'lore &he &heories and &e*hniques &e*hniques behind 'ro*edures o! de,elo'in( a hi(h 're*ision *os&-e!!e*&i,e . millin( ma*hine# This ne/l desi(ned ma*hine &ool *an be /idel used in an indus&r /here small 'ar&s are made# arious s&ru*&ures /ere e+'lored and *om'ared durin( &he manu!a*&urin( s&a(e /hile kee'in( in mind &he limi&ed resour*es /e had a& our dis'osal#
ii
ABSTRACT
This re'or& aims &o e+'lore e+'lore &he &heories and &e*hniques &e*hniques behind 'ro*edures o! de,elo'in( a hi(h 're*ision *os&-e!!e*&i,e . millin( ma*hine# This ne/l desi(ned ma*hine &ool *an be /idel used in an indus&r /here small 'ar&s are made# arious s&ru*&ures /ere e+'lored and *om'ared durin( &he manu!a*&urin( s&a(e /hile kee'in( in mind &he limi&ed resour*es /e had a& our dis'osal#
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AC%NO/LEDGEMENTS
$e /ould like &o e+'ress sin*ere a''re*ia&ion &o our ad,isor ro!# "r# $asim $asim A# A# %han !or his *onsis&en& *onsis&en& (uidan*e and ,i&al su''or& su''or& &hrou(hou& &he en&ire& en&ire& o! &his Final 3ear roe*& roe*& 5F36# 5F36# ur s'e*ial &hanks also (o &o Mr# 8 ameel Mr# M r# %hurshid o! &he . Train Trainin( in( :ab in FM; FM; !or &heir &heir in,alu in,aluabl ablee (uidan (uidan*e *e durin( durin( &he !abri* !abri*a& a&ion ion 'ro*ess# 'ro* ess#
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Table o! on&en&s I#troductio########################### ####################################### ########################### ########################### ########################### ########################### ########################### ########################### ############################ ############### <
Objective........................ Objective......................................... .................................. ....................................................... ................................................ .......... 8 Methodology................... Methodology..................................... ................................... ................................... ............................................... ............................. 8 CHA)TER -########################## ####################################### ########################### ########################### ########################### ########################### ########################### ####################################### ######################### 12
1.1 Market Research...... Research....................... ................................... ................................... ......................................... ............................. ..... 12 1.2 General Research Objectives.............................. Objectives............................................... ................................... ..................... ... 13 1.3 Suary.......................... Suary............................................ ................................... ...................................................... ..................................... 1! CHA)TER +########################## ####################################### ########################### ########################### ########################### ########################### ########################### ####################################### ######################### 1<
:i&era&ur :i&era&uree =e,ie/########## =e,ie/####################### ########################### ########################### ########################### ########################### ########################### ########################### ###################################1< ######################1<
2.1 "#" "once$ts...................... "once$ts....................................... .................................. .................................................... ................................... 1% 2.2 &esign consideration consideration o' "#" achine tools....................................... tools............................................. ......2( 2( 2.3 Suary.......................... Suary............................................ ................................... ...................................................... ..................................... 23 CHA)TER 0########################## ####################################### ########################### ########################### ########################### ########################### ########################### ####################################### ######################### 24
S&ru*&ure "esi(n and Analsis###########################################################################################################24
3.1 Structure Mechanical &esign..................................... &esign.............................................................. ............................... ...... 24 )or*ue )or*ue "alculations "alculations+................... +..................................... ................................... ................................... ...............................2% .............2% Theore&i* Theore&i*al al 'o/er 'o/er e,alua&i e,alua&ion######## on###################### ########################### ########################### ########################### ########################### ############################################## ################################ 27 u&&in( For*e "is&ribu&ion "is&ribu&ion ......................................................................................2%
3.2 ",& &esign........................ &esign......................................... ................................... ................................... .................................... ................... 32 ####################################### ########################### ########################### ########################### ########################### ########################### ####################################### ######################### >4 CHA)TER 1########################## Ma*hine Ma*hine Fabri*a&i Fabri*a&ion###### on#################### ########################### ########################### ########################### ########################### ########################### ########################### ########################### ##################### ######## >4
4.1 Selection o' "o$onents..................................... "o$onents....................................................... .................................... .................... 34 4.1.1
Selection o' otors............................. otors.............................................. ................................... ........................ ...... 34 4
4.1.2
Selection o' linear guides and lead scre-s.................................. scre-s.................................. 3
4.1.3
"ost suary.......................... suary........................................... ................................... ................................. ................. 38
4.2 ,ssebling o' Machine........................ Machine.......................................... ..................................................... ................................... 4( CHA)TER 2########################## ####################################### ########################### ########################### ########################### ########################### ########################### ####################################### ######################### 42
;le*&roni*s on&rol and So!&/are Module########################################################################################42
!.1 General Overvie-......................... Overvie-........................................... ................................... ............................... ......................... ........... 42 !.2 /ork 0lo- Overvie-................................. Overvie-.................................................. ................................................ ............................... 43 !.3 lectronic ard-are ,rchitecture ,rchitecture Overvie-.................................. Overvie-............................................. ........... 44 !.4 So't-are Overvie- and usti'ication............................... usti'ication................................................. .......................... ........ 4! CHA)TER .########################## ####################################### ########################### ########################### ########################### ########################### ########################### ####################################### ######################### 47
-on*lusion############ -on*lusion########################## ########################### ########################### ########################### ########################### ########################### ########################### ########################### ##############################47 #################47
.1 0uture studies....................... studies......................................... ................................... .................................. ................................. ................ 48 ######################################### ########################### ########################### ########################### ########################### ############################################### ################################# 49 REFERENCES########################### A))ENDI3 A########################### ######################################## ########################### ########################### ########################### ########################### ########################### ########################### ####################### ########## ?0 A))ENDI3 B########################### ######################################## ########################### ########################### ########################### ########################### ########################### ########################### ####################### ########## ?4 A))ENDI3 C########################### ######################################## ########################### ########################### ########################### ########################### ########################### #################################### ###################### ?7
!
I#troductio#
@n modern . ss&ems end-&o-end *om'onen& desi(n is hi(hl au&oma&ed usin( om'u&er-Aided "esi(n 5A"6 and om'u&er-Aided Manu!a*&urin( 5AM6 'ro(rams# The 'ro(rams 'rodu*e a *om'u&er !ile &ha& is in&er're&ed &o e+&ra*& &he *ommands needed &o o'era&e a 'ar&i*ular ma*hine ,ia a 'os& 'ro*essor and &hen loaded in&o &he . ma*hines !or 'rodu*&ion# Sin*e an 'ar&i*ular *om'onen& mi(h& require &he use o! a number o! di!!eren& &ools – drills sa/s e&*# modern ma*hines o!&en *ombine mul&i'le &ools in&o a sin(le *ell# @n o&he r ins&alla&ions a number o! di!!eren& ma*hines are used /i&h an e+&ernal *on&roller and human or robo&i* o'era&ors &ha& mo,e &he *om'onen& !rom ma*hine &o ma*hine# @n ei&her *ase &he series o! s&e's needed &o 'rodu*e an 'ar& is hi(hl au&oma&ed and 'rodu*es a 'ar& &ha& ma&*hes &he ori(inal A" desi(n as 'er a**e'&able &oleran*es#
$i&h &he on-(oin( de,elo'men& o! &e*hnolo( and e*onom ne/ indus&rial requiremen&s su*h as hi(h 're*ision (ood quali& hi(h 'rodu*&ion ra&es and lo/ 'rodu*&ion *os&s are in*reasin(l demanded# Mos& o! su*h requiremen&s in*ludin( dimensional a**ura* *on!orman*e &o &oleran*es o! !inished 'rodu*&s and 'rodu*&ion ra&e *an be me& /i&h be&&er ma*hine &ools# $i&h &he hel' o! . &e*hnolo( ma*hine &ools &oda are no& limi&ed &o human *a'abili&ies bu& are able &o make ul&ra-'re*ision 'rodu*&s do/n &o .ano s*ales in a mu*h !as&er manner# The &radi&ional desi(n 'hiloso'h o! ma*hine &ools is mul&i-!un*&ionali& and hi(hes& 're*ision 'ossible# Bo/e,er /i&h &he drama&i* in*rease o! indus&r ,arie&ies and &he (ro/in( demand o! minia&ure 'rodu*&s &hese (eneral 'ur'ose ma*hine &ools are no& e!!i*ien& ei&her in &erms o! ma*hinin( &ime or *os& in manu!a*&urin( 'rodu*&s /i&h s'e*ial sizes and 're*ision requiremen&s#
There are se,eral ad,an&a(es o! usin( small ma*hines &o 'rodu*e small sized obe*&s# $i&h a smaller ma*hine size s'a*e is sa,ed# The ener( required &o o'era&e &he ma*hine is redu*ed as /ell# @& no/ requiresless ma&erial and *om'onen&s &o make &he
ma*hine hen*e brin(in( do/n &he *os& (rea&l# The /ei(h& o! mo,in( *om'onen& also *omes do/n so &ha& durin( o'era&ion &he ,ibra&ion and noise as /ell as 'ollu&ion &o &he en,ironmen& are markedl redu*ed# As &he ma*hine be*omes denser and li(h&er i& be*omes more 'or&able# The laou& o! &he manu!a*&urin( 'lan& *an be more !le+ible# The 'rodu*&i,i& and manu!a*&urin( s'eed also in*reases due &o 'ossible !as&er o'era&ion#
%
O45!ctiv!:
The idea behind !abri*a&ion o! lo/ *os& . Millin( Ma*hine is &o !ull !ill &he demand o! . ma*hines !rom small s*ale &o lar(e s*ale indus&ries /i&h o'&imized lo/ *os&# A maor ne/ de,elo'men& in *om'u&er &e*hnolo( is &he a,ailabili& o! lo/-*os& o'en sour*e hard/are su*h as &he Arduino mi*ro*on&roller# An ad,an&a(e o! o'en sour*e hard/are is &ha& a /ide ,arie& o! read-&o-use so!&/are is a,ailable !or &hem on &he $ebC &here!ore &he 'ro&o&'in( and de,elo'men& &imes are dras&i*all redu*ed# Moreo,er a /ide ran(e o! lo/-*os& in&er!a*es and a**essories su*h as Ma*h> . *on&rol so!&/are are also a,ailable# Bo/e,er !or &he de,elo'men& o! lo/-*os& models o! . ma*hines su*h &ools ma be qui&e adequa&e !rom &he ,ie/'oin& o! ma*hine *on&rol# @n &his 'roe*& &he de,elo'men& o! a 'ro&o&'e >-a+is . Millin( Ma*hine is 'resen&ed /i&h &he !ollo/in( s'e*i!i*a&ion# D ;asil o'erable D ;as in&er!a*e D Fle+ible D :o/ 'o/er *onsum'&ion
M!t"odolo$y: This 'roe*& has been *lassi!ied in&o &he !ollo/in( modules !or su**ess!ul e+e*u&ionE D
Me*hani*al "esi(n
D
;le*&roni*s and on&rol Module
D
So!&/are Module
Bo/ &his ss&em /orks is qui&e a sim'le 'ro*edure# The ma*hine o'era&or in'u&s &he and M *ode in&o &he G@ 5ra'hi* Gser @n&er!a*e6 /hi*h &hen sends &he and M *ode &o &he so!&/are /hi*h in&er're&s &he *ode and sends &he si(nals &o &he ele*&roni* dri,er# The dri,er &hen runs &he mo&ors /hi*h are *onne*&ed &o &he lead s*re/s &ha& are res'onsible !or &he mo,emen& o! &he &ool# 8
M!c"a#ical Syst!6
The me*hani*al ss&em is assembled in su*h a /a &ha& &he >-a+is mo,emen& is a*hie,ed b usin( &he linear bearin(s and (uide rods# S&e''er mo&ors are moun&ed &o ea*h a+is /hi*h is &he sour*e o! mo&ion a*&ed a**ordin( &o &he *on&rol si(nal (enera&ed !rom &he ele*&roni*s *ir*ui&# ;a*h s&e''er mo&or is *ou'led &o &he s*re/ rod /hi*h *arries nu& /i&h &he hel' o! *ou'lin( bush# This s*re/ rod and nu& arran(emen& is res'onsible !or *on,er&in( &he ro&a&ional mo&ion o! &he s&e''er mo&or &o linear mo&ion# The linear mo&ion o! ea*h a+is is *arried a/a smoo&hl b &he linear bearin( and (uide rod assembl *onne*&ed &o &he ea*h a+is /hi*h is *a'able o! load *arriers and allo/s linear mo&ion in ea*h a+is# The *on&rolled mo&ion in ea*h a+is is a*hie,ed dire*&l b *on&rollin( &he ro&a&ion o! &he s&e''er mo&or# The s'eed o! &he mo&ion in ea*h a+is *an also be *on&rolled b dire*& *on&rol o! &he s'eed o! &he s&e''er mo&or b (i,in( required *on&rol si(nals# Thus &he &ool 'a&h o! &he s'indle !i+ed &o &he end e!!e*&or is *on&rolled in ea*h a+is !or smoo&h *ar,in( or *u&&in( a*&ion o! /ork 'ie*e# El!ctrical Syst!6
;le*&roni*s ss&em *om'rises o!E D
o/er su''l
D
Mi*ro*on&roller board
•
S&e''er mo&or dri,er board
)o7!r Su((ly
o/er su''l is hear& o! &he . ss&em /hi*h *on,er&s &he A ,ol&a(e &o " ,ol&a(e and su''lies required ,ol&a(es &o &he *orres'ondin( de, i*es# Mi*ro*on&roller board o'era&es a&?, su''l /hereas &he s&e''er mo&or board o'era&es a& 12,#
St!((!r Motor Driv!r Board
Toshiba T)
o'era&ion is *hosen &o dri,e &he .;MA 17 s&e''er mo&or# S&e''er mo&or "ri,er )oard re*ei,es &he *on&rol si(nal !rom &he mi*ro*on&roller board &o &he &erminals G:S; and "@= /hi*h (enera&es &he *orres'ondin( di(i&al 'ulse si(nals !or s&e''er mo&or &o *on&rol &he ro&a&ion o! &he mo&or# Sot 7ar! Syst!6
The so!&/are &ool *hain o! .-based manu!a*&urin( is re'resen&ed in &he !i( 1# The 'ar& &o be ma*hined is desi(ned in *om'u&er-aided desi(n 5A"6 so!&/are /hose ou&'u& is a dra/in( in one o! man a**e'&able !orma&s mos& 're!erable !orma& is #s&l !orma&# This dra/in( is &hen !ed &o &he *om'u&er-aided manu!a*&urin( 5AM6 so!&/are /hose ou&'u& is &he ma*hine readable *ode used !or numeri*al *on&rol o! &he ma*hine# Sin*e im'lemen&a&ion o! &he *ode is ma*hine de'enden& i& is ne*essar &o &es& ou& di!!eren& *hoi*es !or an o'en sour*e *ode in&er're&er !or Toshiba T)
Co#clusio#:
$i&h &he in*reasin( demand !or small s*ale hi(h 're*ision 'ar&s in ,arious indus&ries &he marke& !or small s*ale ma*hine &ools has (ro/n subs&an&iall# Gsin( small ma*hine &ools &o !abri*a&e small s*ale 'ar&s *an 'ro,ide bo&h !le+ibili& and e!!i*ien* in manu!a*&urin( a''roa*hes and redu*e *a'i&al *os& /hi*h is bene!i*ial !or small business o/ners# @n &his re'or& a small s*ale &hree a+is . millin( ma*hine is desi(ned and !abri*a&ed under ,er limi&ed bud(e&#
Sco(! or Futur! 7or8:
@& is 'lanned &o s*ale u' &he 'ro&o&'e . ma*hine in &erms o! size use more 'o/er!ul mo&ors s&ren(&hen &he !rame and /ork&able /i&h ma&erials like aluminum or *as& iron and au(men& &he . *on&rol so!&/are /i&h so!&/are !or simula&ion ahead o! a*&ual run# For ins&ru*&ional 'ur'oses as /ell as !or more 're*ise o'era&ion i& is 're!erable &o build . ma*hines /i&h " or A ser,omo&ors and en*oder !eedba*k usin( 1
based mo&ion *on&rollers#
1
CHA)TER -*- Mar8!t R!s!arc" The de,elo'men& o! . ma*hine &ools has *on&inued !or o,er !i!& ears in &he manu!a*&urin( indus&r# urren&l &he &e*hnolo( is reasonab l ma&ure and di!!eren& *om'anies ha,e de,elo'ed &heir unique s&ren(&hs on di!!eren& 'rodu*&s# ;uro'e is &he lar(es& ma*hine &ool manu!a*&urer in &he /orld H19I#
Figure-: 1 Mini CNC Engraving M achine (Picture courtesy: China CNC Zone)
The ma*hine sho/n in Fi(ure-E 1 is a &'i*al . en(ra,in( ma*hine made b a hinese manu!a*&urin( *om'an in han(sha# @& is *laimed &o a*hie,e a resolu&ion o! >0 Jm and re'ea&abili& be&&er &han >0 Jm# The in&er're&a&ion and in&er'ola&ion is done usin( a . *on&rol 'a*ka(e so!&/are *alled Ma*h># The ma*hine onl *os&s ?00 GS" in*ludin( e,er&hin( required &o run &he ma*hine e+*e'& a # This &'e o! ma*hine is ,er 'o'ular in hina# Bo/e,er be*ause o! i&s lo/ s&i!!ness and *on&roller robus&ness i& *an onl ma*hine so!& ma&erial su*h as /oods and so!& aluminum#
-*+ G!#!ral R!s!arc" O45!ctiv!s The (eneral obe*&i,e o! &his resear*h is &o de,elo' a mini . ma*hine 'ro&o&'e u' &o indus&riall a**e'&able 're*ision and re'ea&abili& /i&h a ,er limi&ed bud(e& 52000GS"6# This resear*h /ill address all &he required 'ro*edures !or de,elo'in( a *ommer*ial 'rodu*& in a ma*hine &ool *om'an !rom &he earl desi(n s&a(e &o &he subsequen& 'a*ka(in( and marke&in( s&a(e# arious ne/ me&hods and 'rodu*&s is dis*ussed and used &o ei&her redu*e *os& or im'ro,e 'er!orman*e# To a**om'lish &hese obe*&i,es &his resear*h is di,ided in&o a number o! &asks# The resear*h &asks *an be summarized as !ollo/sE 516 Ma*hine desi(n# The bo+ ,olume is *hosen &o *ome u' /i&h an o'&imal s&ru*&ure and size !or &he ma*hine as i&s size de'ends on &he bo+ ,olume i#e# ma+imum ,olume o! &he /ork 'ie*e &ha& *an be in*or'ora&ed !or ma*hinin(
Figure-: 2 Relationship et!een o" volu#e an$ #achine si%e
526 Torque al*ula&ions# Torque required &o mo,e &he &ool in &he > a+es a**ordin( &o &he bo+ ,olume is *al*ula&ed# 5>6 Ma*hine !abri*a&ion# All &he bod 'ar&s /ill be ma*hined and &he *om'onen&s /ill be
'ur*hased &hrou(h ,arious su''liers# 546 Assemblin( &he Ma*hine# Ma*hine /ill be assembled inside &he lab#
-*0 Su66ary @n &his *ha'&er an o,er,ie/ o! &he mo&i,a&ion and 'ro*edure o! de,elo'in( a *os&e!!e*&i,e mini . ma*hine is (i,en# The *urren& marke& is in la*k o! an a!!ordable small-s*ale hi(h 're*ision ma*hine &ool ss&em &ha& *an be used !or small ,olume 'rodu*&ion# The ma*hine des*ribed in &his re'or& /ill hel' &o sol,e &his 'roblem and ser,e &hose /ho /an& &o make small &hin(s bu& do no& /an& &o s'end mone on bi( ma*hine#
CHA)TER + Lit!ratur! R!vi!7 The !irs& numeri*al *on&rol 5.6 millin( ma*hine /as *on*ei,ed b Mr# 8ohn T# arsons around 1940s-19?0s H14I# arsons /orked &o a&&a*h ser,omo&ors &o &he + and a+is o! a manual o'era&ed ma*hine &ool &o *on&rol &hem /i&h a *om'u&er &ha& read 'un*h *ards &o (i,e i& 'osi&ionin( ins&ru*&ions# The reason !or de,isin( su*h a ss&em /as &o ma*hine *om'le+ sha'es like ar*s &ha& *an be made in&o air!oils !or air'lanes# This /as no& a &ri,ial &ask &o a&&em'& /i&h a manual millin( ma*hine so &he . millin( ma*hine /as born# TodaKs modern ma*hiner is . 5om'u&er .umeri* on&rol6 millin( ma*hines and la&hes# A mi*ro'ro*essor in ea*h ma*hine reads &he -ode 'ro(ram &ha& &he user *rea&es and 'er!orms &he 'ro(rammed o'era&ions# ersonal *om'u&ers are used &o desi(n &he 'ar&s and are also used &o /ri&e 'ro(rams b ei&her manual &'in( o! ode or usin( AM 5om'u&er Aided Manu!a*&urin(6 so!&/are &ha& ou&'u&s -ode !rom &he users in'u& o! *u&&ers and &ool 'a&h# @n &his *ha'&er some li&era&ure rele,an& &o . *on*e'&s and (eneral desi(n and *on&rol o! . ma*hine /ill be re,ie/ed# The numeri*al *on&rol as'e*& are &he !o*us in &his re,ie/#
+*- CNC Co#c!(ts An im'or&an& ad,an*e in &he 'hiloso'h o! . ma*hine &ools /as &he shi!& &o/ard &he use o! *om'u&ers ins&ead o! 'ro'rie&ar *on&roller uni&s in &he . ss&em o! &he earl 1970s# This (a,e rise &o &he *om'u&er numeri*al *on&rol 5.6# . is a sel!*on&ained . ss&em !or a sin(le ma*hine &ool in*ludin( a dedi*a&ed mini*om'u&er *on&rolled b s&ored ins&ru*&ions &o 'er!orm some or all o! &he basi* . !un*&ions H1I# @& has be*ome /idel used !or manu!a*&urin( ss&ems mainl be*ause o! i&s !le+ibili& and less in,es&men& required# =e'la*in( *on,en&ional . hard/are /i&h so!&/are as as mu*h 'ossible and sim'li!in( &he remainin( hard/are is one o! &he obe*&i,es o! . ss&ems# $hile mos& in&er're&a&ion and in&er'ola&ion !un*&ions *an be re'la*ed b 'ro'er so!&/are &he remainin( hard/are mus& *on&ain a& leas& ser,o am'li!iers &ransdu*er *ir*ui&s and in&er!a*e *om'onen&s as sho/n in Fi(ure-E >
Figure-: & 'che#atic o CNC syste#
The so!&/are 'or&ion o! a . ss&em mus& *onsis& a& leas& o! &hree maor 'ro(ramsE a 'ar& 'ro(ram a ser,i*e 'ro(ram and a *on&rol 'ro(ram H11I# The 'ar& 'ro(ram *on&ains &he (eome&r des*ri'&ion o! &he 'ar& bein( 'rodu*ed and &he *u&&in( *ondi&ions su*h as s'indle s'eed and !eedra&e# om'u&er Aided Manu!a*&urin( 5AM6 so!&/are *an be used &o (enera&e &his 'ar& 'ro(ram# The ser,i*e 'ro(ram is used &o *he*k edi& and *orre*& &he 'ar& 'ro(ram# @& usuall has a user in&er!a*e &ha& allo/s &he user &o o'era&e &he ma*hine easil# The *on&rol 'ro(ram a**e'&s &he 'ar& 'ro(ram as in'u& da&a and 'rodu*es si(nals &o dri,e &he a+es o! mo&ion# @& 'er!orms in&er'ola&ion !eed ra&e *on&rol a**elera&ion and de*elera&ion and 'osi&ion *oun&ers sho/in( &he *urren& a+es 'osi&ion H11I# Mos& *losed-loo' . ss&ems in*lude bo&h ,elo*i& and 'osi&ion *on&rol loo's# The ,elo*i& !eedba*k is usuall 'ro,ided b a &a*home&er and &he 'osi&ion !eedba*k is usuall 'ro,ided b an en*oder or resol,er# . so!&/are *an also re&rie,e ,elo*i&
!eedba*k !rom en*oder b di!!eren&ia&in( &he in'u& si(nal H11I# The *om'u&er ou&'u& in . ss&ems *an be &ransmi&&ed ei&her as a sequen *e o! re!eren*e 'ulses or as a binar /ord# @! &he re!eren*e 'ulse sequen*e is (enera&ed ea*h 'ulse (enera&es a mo&ion o! 1 ):G o! a+is &ra,el# The number o! 'ulses re'resen&s 'osi&ion and &he 'ulse !requen* re'resen&s a+is ,elo*i&# @n an o'en-loo' ss&em &hese 'ulses are &he *on&rol si(nal o! a s&e''er mo&or# @n a *losed-loo' ss&em &hese 'ulses *an be !ed as a re!eren*e si(nal H11I
+*+ D!si$# co#sid!ratio# o CNC 6ac"i#! tools . ma*hine &ools mus& be be&&er desi(ned and *ons&ru*&ed and mus& be more a**ura&e &han *on,en&ional ma*hine &ools# @& is ne*essar &o minimize all non-*u&&in( ma*hine &ime b !as& &ool *han(in( me&hods and minimize idle mo&ions b in*reasin( &he ra'id &ra,erse ,elo*i&ies &o make &he use o! &he ma*hine &ool more e!!i*ien&# "i(i&al *on&rol &e*hniques and *om'u&ers ha,e undoub&edl *on&ribu&ed &o be&&er a**ura* and hi(her 'rodu*&i,i&# Bo/e,er i& should be no&ed &ha& i& is &he *ombined *hara*&eris&i*s o! &he ele*&ri* *on&rol as /ell as &he me*hani*al desi(n o! &he ma*hine &ool i&sel! &ha& de&ermine &he !inal a**ura* and 'rodu*&i,i& o! &he . ma*hine &ool ss&em# Bi(h 'rodu*&i,i& and a**ura* mi(h& be *on&radi*&or H11I# )e*aus hi(h 'rodu*&i,i& requires hi(her !eed s'eed and de'&h o! *u& /hi*h in*reases &he hea& and *u&&in( !or*es in &he ss&em# This /ill lead &o hi(her de!le*&ions &hermal de!orma&ions and ,ibra&ion o! &he ma*hine /hi*h resul&s in a**ura* de&eriora&ion# There!ore &o a*hie,e hi(h o'era&in( band/id&h /hile main&ainin( rela&i,el hi(h a**ura* &he s&ru*&ure o! . ma*hine &ool mus& be more ri(id and s&i!! &han i&s *on,en&ional *oun&er'ar&# To a*hie,e be&&er s&i!!ness and ri(idi& o! s&ru*&ure se,eral !a*&ors should be *onsidered in &he desi(n# The !irs& *on*ern is &he ma&erial# on,en&ional ma*hine &ools are
made
o!
*as&
iron#
Bo/e,er
&he
s&ru*&ures
o!
.
ma*hines
are
usuall all-s&eel-/elded *ons&ru*&ed &o a*hie,e (rea&er s&ren(&h and ri(idi& !or a (i,en /ei(h&# @n addi&ion be&&er a**ura* is ob&ained in . ma*hines b usin( lo/-!ri*&ion
mo,in( 'ar&s a,oidin( los& mo&ions and isola&in( &hermal sour*es# =e(ular slidin( (uides ha,e hi(her s&a&i* !ri*&ion &han &he slidin( !ri*&ion# The !or*e used &o o,er*ome &he s&a&i* !ri*&ion (ro/s &oo lar(e /hen &he (uide s&ar&s &o mo,e# "ue &o iner&ia o! &he slide &he 'osi&ion (oes beond &he *on&rolled 'osi&ion addin( o,ershoo& and 'hase la( &o &he ss&em res'onse and a!!e*&s &he a**ura* and sur!a*e !inish o! &he 'ar&# This *an be a,oided b usin( slides and lead s*re/s in /hi*h &he s&a&i* !ri*&ion is lo/er &han &he slidin( !ri*&ion H11I# @n our Ma*hine /e are (oin( &o use ball-bearin( lead s*re/ as sho/n in Fi(ure-E 4# "e&ailed dis*ussion o! sele*&in( &his *om'onen& /ill be in*luded in *ha'&er 4#
Figure-: *all-earing lea$ scre!
enerall s'eakin( &he en&ire ma*hine *om'onen& mus& use ri(id and s&ron( ma&erial# The s'indle should ha,e hi(h s&ren(&h sus&ain a hi(h &em'era&ure and be su''or&ed b lar(e bearin(# The *lam' ss&em should be s&ron( enou(h &o hold /ork 'ie*e /hen &he ma*hine !a*es a mo,eable 'ar& durin( &he manu!a*&urin( 'ro*ess# @n addi&ion *lam'in( ss&em should be e!!i*ien&l mo,ed !as& in *lam'in( or un*lam'in( &he /ork 'ie*e /i&h !as& mo,emen& durin( &he 'ro*ess# The *hoosin( o! *u&&in( &ools is im'or&an& in order &o make sure i& /ill no& break /hen *u&&in( &he /ork 'ie*eH11I#
+*0 Su66ary @n *on*lusion &his *ha'&er mainl summarizes some ke *on*e'&s o! *om'u&er numeri*al *on&rol and desi(n *onsidera&ion o! . ma*hine &ools men&ioned in li&era&ure# These *on*e'&s are im'lemen&ed in &he /hole desi(n 'ro*ess in &his 'roe*&# Se,eral *om'onen&s are *hosen based on &he reasons dis*ussed in se*&ion 2#2# The *on&roller ar*hi&e*&ure used in &he !inal s&a(e e+a*&l !ollo/s &he *on*e'&s o! . so!&/are des*ribed in se*&ion 2#1# The li&era&ure 'ro,ides *lear ba*k(round kno/led(e and (uidan*e !or &he de,elo'men& o! a small s*ale . ma*hine &ool#
CHA)TER 0 Structur! D!si$# a#d A#alysis Ma*hine s&ru*&ure is &he Lba*kbone o! &he ma*hine &ool# @& in&e(ra&es all ma*hine *om'onen&s in&o a *om'le&e ss&em# The ma*hine s&ru*&ure is *ru*ial &o &he 'er!orman*e o! &he ma*hine &ools sin*e i& is dire*&l a!!e*&in( &he s&a&i* and dnami* s&i!!ness as /ell as &he dam'in( res'onse o! &he ma*hine &ool# A *are!ull desi(ned s&ru*&ure *an 'ro,ide hi(h s&i!!ness resul& in hi(her o'era&ion band/id&h and more 're*ise o'era&ion# A smalls*ale ma*hine &ool (enerall requires e,en hi(her s&i!!ness &han &he ordinar lar(e-s*ale ma*hine &ool sin*e i& is usuall o'era&ed a& hi(her s'eeds# There are se,eral o&her issues rela&ed &o &he ma*hine s&ru*&ure su*h as smme&r *onne*&i,i& and errors# @n &his *ha'&er some mos& *ommon s&ru*&ures used on ma*hine &ools /ill be *om'ared and analzed#
0*- Structur! M!c"a#ical D!si$# The &/o mos& *ommon ma*hine s&ru*&ures in &he indus&r are o'en !rame s&ru*&ures and *losed !rame s&ru*&ures# enerall s'eakin( &he *losed !rame s&ru*&ure 'ro,ides a s&ron( rid(ed s&ru*&ure loo' smme&r and (ood &hermal s&abili& /hi*h 'ro,ides be&&er s&i!!ness &han &he o'en !rame s&ru*&ures (enerall used !or eas a**ess &o &he /ork zone /i&h &he same order-o!-ma(ni&ude in size# losed !rame s&ru*&ures &'i*all are used in
lar(e 're*ision ma*hines su*h as MMs# The /ork 'ie*es &o be ma*hined or measured are (enerall lar(e and hea,# There!ore i& is mu*h easier &o mo,e &he &ool /i&h res'e*& &o a !i+ed /ork 'ie*e# This s&ru*&ure *onsumes more ma&erial hen*e is more e+'ensi,e &o build# 'en !rame ma*hine &ool s&ru*&ure is also *alled a or s&ru*&ure# This s&ru*&ure is ,er *ommonl seen in small ma*hines# Al&hou(h &he s&ru*&ure is asmme&ri*al /hi*h leads &o undesirable &hermal (radien&s and bendin( mo men&s i&Ks an ideal s&ru*&ure !or small ma*hines# The /ork 'ie*es are usuall small and li(h& so &he ma&erial remo,al ra&e is mu*h smaller &han &hose bi( /ork 'ie*es made b &he bi( ma*hine so &he error *aused b &hermal e!!e*&s is no& a si(ni!i*an& issue# A *ri&i*al 'ar& o! &he s&ru*&ure is *an&ile,ered /hi*h leads &o Abbe errors 5ma(ni!i*a&ion o! an(ular error o,er dis&an*e6 H17I bu& &his *an be *om'ensa&ed b s'rin( loadin( in &he o''osi&e dire*&ion or 're*om'ensa&in( bendin( in desi(n# The ma&erial required &o *ons&ru*& &his s&ru*&ure is also less &han &he *lose !lame s&ru*&ure and hen*e mu*h *hea'er &o make# A!&er e,alua&in( &he 'ros and *ons o! bo&h s&ru*&ures &he &eam de*ides &o use an o'en !rame s&ru*&ure !or &his small s*ale ma*hine# There are man di!!eren& ,aria&ions on an o'en !rame s&ru*&ure# enerall &he *an be (rou'ed in&o &/o *a&e(ories dis&in(uished b &he &ool orien&a&ion i#e# ,er&i*al &ool 'osi&ion and horizon&al &ool 'osi&ion# @n &he horizon&al *on!i(ura&ion &he /ork 'ie*e is !i+ed on ,er&i*al N3 'lane /hi*h requires &he /ork 'ie*e &o be li(h& and *om'a*&# The Abbe error on N3 'lane is no&
si(ni!i*an& be*ause &he /ei(h& o! /ork 'ie*e is ,er small and *an be ne(le*&ed# S'indle is moun&ed horizon&all &o ensure ma+imum s&i!!ness alon( Z a+is# This is &he ideal s&ru*&ure !or mi*ro-manu!a*&urin( ma*hine &ools# Bo/e,er &he len(&h s*ale o! &he /ork 'ie*es &o be ma*hined is desi(ned &o be be&/een 10mm and 70mm# The /ei(h& e!!e*& o! &he /ork 'ie*e /i&h &his len(&h s*ale *anno& be i(nored !or i& *rea&es *hallen(e &o !i+ &he /ork 'ie*e on&o &he ,er&i*al N3 'lane# "ue &o &his *ru*ial si&ua&ion &he ma*hine is desi(ned &o ha,e &'i*al ,er&i*al &ool 'osi&ion o'en !rame s&ru*&ure#
Tor9u! Calculatio#s: THEORETICAL )O/ER EAL;ATION Cutti#$ Forc! Distri4utio#
The &ask a& hand is &o *al*ula&e &he ,alue o! &he &orque required !or &he a+es mo&ors# $e s&ar& b *al*ula&in( &he ,alue o! &he *u&&in( !or*es /hi*h are (i,en in &he !ollo/in( Fi(ure-EE
Figure-: + Forces $uring cutting •
The !or*e e+er&ed on &he /ork 'ie*e is labeled
•
in&o i&s *om'onen&s and # The /ork 'ie*e is ri(idl moun&ed on &he /ork&able so &here is no rela&i,e mo&ion be&/een &hem#
2
5u&&in( For*e6 and is di,ided
The ,alues o! &he *u&&in( !or*es are *al*ula&ed usin( &he !ormulaE F O &+/ $hereE F- 'rin*i'al *u&&in( !or*e in .e/&ons - ma&erial *ons&an& a& a (i,en *u&&in( s'eed and rake an(le &- un*u& *hi' &hi*kness in mm /- /id&h o! *u& in mm or len(&h o! &he *u&&in( ed(e in en(a(emen& +- *ons&an& !or ma&erial bein( ma*hined# + ,aries /i&h &he rake an(le $e sele*&ed &he /ork 'ie*e &o be made o! Aluminum so &he ,alues o! &he *ons&an&s /ere &aken &o be &he !ollo/in( O?00 &O0#1? +O0#70 /O20 Ben*e F*+ O &+/ F*+ O ?00+0#1?0#70+20 F*+ O 2>0 + &an 541#>46 O 2>>0. 2
The &o&al ,alue o! &he !or*e o''osin( &he mo&ion o! &he +-a+is -a+is mo&ors is (i,en b &he !ollo/in( !ormulaE
$here $& &he &o&al load o! &he /ork 'ie*e bed is &aken &o be >00. 5>0%6 &he ,alue o! &he *oe!!i*ien& o! !ri*&ion is assumed &o be 0#> Ben*e To&al :oad 5:6 O 2>0 Q 2006 + 0#> To&al :oad 5:6 O 42>4 . Calculati#$ t"! Tor9u!
The &hread /e are usin( is &he AM; square &hread# The ,alue o! &he &o&al &orque a''lied on &he square &hread b &he load is (i,en b &he !ormula H1I
For &he AM; square &hread used O 0#07 Mean diame&er dm O 9#?2? mm The 'i&*h l O 2#1 mm Ben*e
O 4#2? .m 2
Tor9u! calculatio#s or tool drivi#$ 6otor tor9u!
The 'arame&ers used in &his se*&ion o! *al*ula&ions are de!ined as !ollo/sE Z O .umber o! &ee&h o! &he &ool
?
d O diame&er o! &ool 5mm6
10 mm
aeO len(&h o! *u& 5*m6
10 mm
a ' O de'&h o! *u& 5*m6
20 mm
! z O Feed ra&e R &oo&h
0#1? mm
% O S'e*i!i* u&&in( o/er 5/a&&s minR*m >6
17 /a&&s minR*m >
. O .umber o! re,olu&ions 5re,Rmin6
79? re,Rmin
! O !eed ra&e
!z + Z + .
O Ma&erial =emo,al =a&e
O o/er 5/a&&s6
ϣ O =o&a&ional S'eed
T O Torque 5.m6 So ! O ! z + Z + . ! O 0#1? + ? + 79? ! O ?9<#2? mmRmin
O
O O 11#92? *m>Rmin
2
O
O O 0#20> %/
Ϣ O
Ϣ O Ϣ O >#2? radRs
TO
TO T O 2#44 .m
3
0*+ CAD D!si$# Gsin( Solid/orks 2014 /e de,elo'ed a de&ailed A" model &ha& /e used !or ,isualiza&ion and simula&ion be!ore /e mo,ed on &o manu!a*&urin(#
Figure-: , ia#etric .ie! o our /nal C0 #o$el
Figure-: Front vie! o our #achines C0 #o$el
3
Figure-: 3 'i$e vie! o our #achines C0 #o$el
Figure-: 4 5op vie! o our #achines C0 #o$el
3
CHA)TER 1 Mac"i#! Fa4ricatio# @n &his *ha'&er &he de&ailed !abri*a&ion 'ro*edure o! &he 'ro&o&'e mini . ma*hine is des*ribed s&ar&in( /i&h &he sele*&ion o! ,arious o!!-&he-shel! *om'onen&s# The reasons behind &he sele*&ion o! ,arious 'ar&s /ill be dis*ussed# The uni& 'ri*e o! all *om'onen&s /ill be lis&ed and summarized in &he *os& summar se*&ion# "e&ails &ha& require e+&ra a&&en&ion /ill be men&ioned durin( &he !abri*a&ion des*ri'&ion#
1*- S!l!ctio# o Co6(o#!#ts
1*-*-
S!l!ctio# o 6otors
Sele*&ion o! mo&ors is *arried ou& !irs& be*ause i& is dire*&l rela&ed &o &he dri,in( me*hanism as /ell as *on&rol me&hod# T/o di!!eren& mo&ors s&e''ers ser,os /ill be dis*ussed# S&e''er mo&or and ser,o mo&or are ro&ar mo&ion mo&ors# ;a*h o! &hem has unique s&ren(&hs and /eaknesses /hi*h make &hem sui&able in *er&ain a''li*a&ions# For ro&ar mo&ion mo&ors a lead s*re/ is al/as needed &o &rans!orm ro&ar mo&ion in&o linear mo&ion# A s&e''er mo&or is an ele*&rome*hani*al de,i*e /hi*h *on,er&s ele*&ri*al 'ulses in&o dis*re&e me*hani*al mo,emen&s# The sha!& or s'indle o! a s&e''er mo&or ro&a&es in 33
dis*re&e s&e' in*remen&s /hen ele*&ri*al *ommand 'ulses are a''lied &o i& in &he 'ro'er sequen*e# The mo&ors ro&a&ion has se,eral dire*& rela&ionshi's &o &hese a''lied in'u& 'ulses# The sequen*e o! &he a''lied 'ulses is dire*&l rela&ed &o &he dire*&ion o! mo&or sha!&s ro&a&ion# The s'eed o! &he mo&or sha!&s ro&a&ion is dire*&l rela&ed &o &he !requen* o! &he in'u& 'ulses and &he len(&h o! ro&a&ion is dire*&l rela&ed &o &he number o! in'u& 'ulses a''lied# Ser,o mo&or in&ernall *on&ains a !eedba*k sensor &o &ell i&s *urren& 'osi&ion /hi*h allo/s 're*ise *on&rol on an(ular 'osi&ion# The indus&rial ser,o mo&or s'eed ou&'u& is 'ro'or&ional &o &he in'u& *urren& le,el# The look 're&& similar &o ea*h o&her bu& &he *on&rol me&hod is *om'le&el di!!eren&# The basi* di!!eren*e be&/een a &radi&ional s&e''er and a ser,o -based ss&em is &he &'e o! mo&or and ho/ i& is *on&rolled# S&e''ers &'i*all use ?0 &o 100 'ole brushless mo&ors /hile &'i*al ser,o mo&ors ha,e onl 4 &o 12 'oles# S&e''ers donU& require en*oders sin*e &he *an a**ura&el mo,e be&/een &heir man 'oles /hereas ser,os /i&h !e/ 'oles require an en*oder &o kee' &ra*k o! &heir 'osi&ion# S&e''ers sim'l mo,e in*remen&all usin( 'ulses Ho'en loo'I /hile ser,os read &he di!!eren*e be&/een &he mo&ors en*oder and &he *ommanded 'osi&ion H*losed loo'I and adus& &he *urren& required &o mo,e# Table-E1 b e l o / summarizes some ke di!!eren*es be&/een ser,o mo&ors and s&e''ers#
34
St!((!r
S!rvo
ri*e
:o/
Bi(h
on&rol
enerall o'en loo'
lose loo'
=esolu&ion
"e&ermine b s&e'Rre,
"e&ermine b en*oder
"nami* beha,ior
:o/ s'eed
Bi(h s'eed allo/ed
A**ura*
:o/ i! usin( mi*ro s&e''in(
Bi(h
5ale-: 1 Co#parison et!een 'tepper an$ 'ervo
S&e''ers are &he mos& a!!ordable a*&ua&in( solu&ion !or ma*hine &ools *urren&l# :o&s o! *ommer*iall a,ailable small . ma*hines in*ludin( . )aron and T=MAB /e men&ioned in *ha'&er one use s&e''er mo&ors &o dri,e &he a+es &o(e&her /i&h an en*oder &o &ell &he *urren& 'osi&ion# The *on&rol is s&ill o'en-loo' /hile &he en*oder is used us& as an e,alua&ion de,i*e &o make minor adus&men&s !or small 'osi&ion o!!se&s#
1*-*+
S!l!ctio# o li#!ar $uid!s a#d l!ad scr!7s
" s&e''er mo&ors are *hosen &o be used as a*&ua&ors !rom las& session# There!ore /e ha,e &o use lead s*re/ me*hanism &o &rans!er ro&ar mo&ion in&o linear mo&ion# $hen sele*&in( &he lead s*re/ /e /an& &o ha,e &he smalles& 'i&*h size 'ossible &o in*rease our resolu&ion# The *urren& marke& has ,arious models and quali& le,els &o *hoose !rom# > is &he mos& 're*ise le,el bu& also &he mos& e+'ensi,e# 7 is &he *hea'es& and mos& *ommonl used le,el# @n le,el 7 002 is &he smalles& 'i&*h size model# 002 s&ands !or mm diame&er and 2mm 'i&*h# $e ha,e 002 1002 1004 1204 1<04 1<0? 3!
&o *hoose !rom# The *hea'es& one is 1<0? bu& i& has &he lar(es& 'i&*h and diame&er# The ma*hine size /ill also be a!!e*&ed b usin( lar(e diame&er lead s*re/s# 002 1002 o!!ers &he smalles& 'i&*h size bu& &he 'ri*e is almos& &ri'led *om'ared /i&h &he 1<0? model# Amon( 1004 1204 and 1<04 model 1004 is &he mos& e+'ensi,e model# 1204 is onl sli(h&l more e+'ensi,e &han 1<04 and o!!ers a mu*h smaller diame&er# There!ore 1204 7 model is sele*&ed as &he lead s*re/ o! our ma*hine# The lead s*re/ *on&ains a 'reloaded *ir*ula&in( ball nu& /hi*h elimina&es ba*klash and redu*es !ri*&ion as sho/n in Fi(ure-E belo/#
Figure-: 16 126 lea$ scre! !ith circulating all nut
There are also ,arious &'es o! linear slides &o *hoose !rom# Fi(ure-E 12 sho/s &he &hree mos& *ommon &'es o! linear slides used in ma*hine &ools i#e# *ross-roller (uide re*ir*ula&in( ball slides and rollin( bearin( slides#
5a6 ross-roller (uide
5b6 =e*ir*ula&in( ball slide
5*6 rollin( bearin( slide
Figure-: 11 7inear sli$ers
Amon( &hree di!!eren& slides rollin( bearin( slides are &he *hea'es& *hoi*e# @& is 3
*om'a*& li(h&/ei(h& and 'ro,ides unlimi&ed ran(e o! mo&ion # Bo/e,er i& is &he leas& s&i!! and has &he lar(es& !ri*&ion one amon( &he &hree# =e*ir*ula&in( ball slides are more e+'ensi,e bu& ha,e less !ri*&ion and are s&i!!er &han rollin( bearin( slides# ross-roller (uides ha,e limi&ed ran(e o! mo&ion bu& eno &he hi(hes& s&i!!ness and robus&ness amon( &hree di!!eren& slides and ha,e &he same le,el o! !ri*&ion as re*ir*ula&in( ball slides# Sin*e /e onl need limi&ed ran(e o! &ra,el in our ma*hine and hi(her s&i!!ness allo/s &he ma*hine &o o'era&e a& mu*h hi(her band/id&h so /i&hin our bud(e& *rossroller (uide is &he bes& *hoi*e#
1*-*0
Cost su66ary
The *os&s o! e,er&hin( required &o make a mini . ma*hine un&il no/ are lis&ed in &he &able 2 It!6
D!scri(tio#
Ma&erial
<0<1 Aluminum 40 k(
)ric!
%= <4000
:eads*re/ V> :eads*re/ !i+ V> sha!& V2 slider V2 Me*hani*al sha!& !i+ V2 *ross roller (uide V4 rubber le( V< sha!&
%= 40000
a**essories *ou'ler V> ;le*&ri*al
S'indle ki& s&e''er mo&ors V> and am'li!ier V> limi& s/i&*h V12 mo&or 'o/er su''l
%= 0000
a**essories To&alE
%= 14000
3%
For no/ &he &o&al *os& is /ell belo/ our bud(e&# $e ha,e a''ro+ima&el ?00 GS" bud(e& &o 'ur*hase or build &he Lbrain o! our mini . ma*hine /hi*h is &he mo&ion *on&roller# The se&u' and desi(n o! mo&ion *on&roller /ill be dis*ussed in de&ail in *ha'&er ?#
38
1*+ Mac"i#! ass!64li#$ A!&er (a&herin( all me&al 'ar&s and a**essories required !or assemblin( &he 'ro*edure o! makin( &he ma*hine is lis&ed belo/ s&e' b s&e'# a6 S&ar& !rom &he base b6 @ns&all si+ rubber le( *6 @ns&all !our /alls o! 3 a+is d6 @ns&all main su''or& !or Z a+is e6 @ns&all Z a+is *hamber !6
Assemble Z a+is leads*re/
(6 Assemble Z a+is leads*re/ and slides h6 Fi+ Z a+is leads*re/ and slides i6
@ns&all Z a+is mo&or
6
)uild N3 a+is s&ar& !rom &able a& &he &o'
k6 @ns&all s*re/ nu& *onne*&or undernea&h &he &able l6 m6 Fi+ leads*re/ n6 @ns&all *ross roller (uide o! N a+is o6 om'le&e N a+is b add !ron& and ba*k *o,er '6 @ns&all leads*re/ benea&h N a+is q6 Fi+ N &able on &he base r6 @ns&all *ross roller (uide s6 @ns&all &/o mo&or and *om'le&e N3 &able &6
om'le&e ma*hine /i&h en*oder and limi& s/i&*h
3
@ns&all leads*re/
A!&er &he ma*hine is !abri*a&ed ali(nmen& o! N and 3 a+is !la&ness o! &he /orkin( &able sur!a*e and ,er&i*alness o! Z a+is are all *are!ull ins'e*&ed b ee and &ools# Se,eral issues o**urred durin( &he assemblin( 'ro*edure# Firs& &he N3 &able is assembled &o'-do/n# This requires a lo& o! s*re/ se*urin( 'ro*edure &o be done u'side do/n# The ali(nmen& is ano&her bi( issue# @! &he s*re/ &hread is sli(h&l o!! i&s desired 'osi&ion &here is no /a &o adus& &he ali(nmen& ba*k &o i&s 'ro'er 'osi&ion# These issues *an be easil i(nored durin( &he desi(n s&a(e so &he ne+& ,ersion o! &he ma*hine /ill in*lude ,arious
adus&in(
!ea&ures
&o
*om'ensa&e
,arious
manu!a*&urin(
de!e*&s#1*0
Su66ary This *ha'&er (i,es a *om'rehensi,e ,ie/ o! ho/ &his 'ro&o&'e ma*hine is !abri*a&ed# The 'ro*ess s&ar&s !rom sele*&in( ,arious ke 'ar&s !ollo/ed b 'ur*hasin( di!!eren& a**essories ra/ ma&erials and ma*hine ra/ me&al 'la&es and ends /i&h &he s&e' b s&e' assemblin( 'ro*edure# The &o&al *os& o! &his 'ro&o&'e e+*ludin( &he mo&ion *on&roller is 1449 GS"# @! &his desi(n e,en&uall (oes &o mass 'rodu*&ion ,olume dis*oun& *an !ur&her redu*e &his *a'i&al *os& &o less &han ?00 GS" 'er ma*hine# The &o&al &ime required &o !abri*a&e one ma*hine is less &han &/o hours#
4(
CHA)TER 2
El!ctro#ics' Co#trol a#d Sot7ar! Modul! 2*- G!#!ral Ov!rvi!7 $e in&end &o desi(n a small-s*ale om'u&er .umeri*all on&rolled 5.6 Millin( ma*hine &o es&ablish and ,alida&e our me&hodolo(ies# @n &he de,elo'men& 'ro*ess /e /ill ensure &ha& /e do*umen& e,er s&e' o! &he 'ro*ess# ur main (oals /ill be user!riendliness and ease o! use so &ha& smaller se&u's and sa,e u' si(ni!i*an&l on *a'i&al *os&s /hen re&ro!i&&in( or buildin( &heir o/n . ma*hines usin( our me&hodolo(ies# The main ad,an&a(es o! su*h an indi(enousl 'rodu*ed ma*hines areE
Su!!i*ien& le,el o! 're*ision and a**ura* in ma*hined /ork 'ar&s
Time sa,in(
=edu*ed labor *os&
;limina&ion o! Buman error
or&abili&
Si(ni!i*an& *a'i&al o'era&in( and main&enan*e *os& sa,in(s
41
2*+ /or8 Flo7 Ov!rvi!7 ur 'roe*& L"esi(n and Fabri*a&ion o! om'u&er .umeri*all on&rolled 5.6 Millin( Ma*hine in,ol,es me*hani*al ele*&ri*al and so!&/are as'e*&s# @n &his se*&ion /e /ill res&ri*& our dis*ussion &o &he *om'u&er-s*ien*e and ele*&ri*al as'e*&s o! &he 'roe*&# Some maor deli,erables ha,e been lis&ed belo/E
"e,elo' a sui&able mi*ro*on&roller-based se&u' &o *on&rol ma*hine 'ro*esses#
Assess use o! sensors and &heir !eedba*k !or ss&em re(ula&ion and *on&rol#
Sele*& and 'ro*ure sui&able mo&ors !or ea*h ma*hine 'ro*ess#
"e,elo' or 'ro*ure a mo&or dri,er *ir*ui&#
"esi(n and !abri*a&e or 'ro*ure and in&e(ra&e a ,ol&a(e re(ula&in( 'o/er
su''l#
"e,elo' sui&able Buman om'u&er @n&er!a*e 5B@6#
"esi(n in&er're&er !or *on,er&in( M *odes in&o ma*hine lan(ua(e#
The !a*& &ha& &hese deli,erables /ere se& on a broader s*o'e /i&hou& s'e*i!in( res&ri*&ions is due &o &he !a*& &ha& /e in&ended &o lea,e room !or ada'&in( our ele*&roni* ar*hi&e*&ure desi(n &o &he a,ailabili& o! ma&erial and de,i*es lo*all and kee'in( in mind &he rela&i,e *os& o! indi(enous desi(n and de,elo'men& andRor !abri*a&ion ,ersus 'ro*uremen& and in&e(ra&ion o! ma&erials de,i*es and *ode# @& is /or&h re-s&a&in( &ha& our mos& maor (uidin( obe*&i,e is &o 'rodu*e an ine+'ensi,e and un*om'li*a&ed . Millin( ma*hine &ha& is able &o ma*hine so!&er me&als /hile kee'in( in mind &he s*alabili& o! &he desi(n# Also &he reader /ill no&e &ha& &he desi(n 'ro*ess /e em'loed /as i&era&i,e and &hus /e *on!ormed &o &he "esi(n !or Manu!a*&urabili& 5"FM6 'hiloso'h# 42
@n our 'roe*& all &he &e*hni*al as'e*&sC Me*hani*al ;le*&ri*al and om'u&erS*ien*e are *losel linked /i&h ea*h o&her *han(e in e,en one o! &he me*hani*al desi(n 'arame&ers dire*&l in!luen*es &he ele*&ri*al *al*ula&ions and *om'u&er 'ro(rammin( and ,i*e ,ersa#
43
2*0 El!ctro#ic Hard7ar! Arc"it!ctur! Ov!rvi!7 The s*hema&i* belo/ hi(hli(h&s &he laou& o! &he ele*&roni* *om'onen&s used in our ma*hine# The arro/s sho/ &he *onne*&ions be&/een de,i*es#
Figure-: 12 'che#atic sho!ing the co#plete electronic architecture o our #achine
S&ar&in( o!! !rom &he &o'-le!& /e ha,e &he mi*ro*om'u&er &ha& has &hree basi* bu& essen&ial @R de,i*es *onne*&ed &o i& namel &he keboard and mouse !or da&a in'u& &o &he ss&em and &he :" Moni&or !or dis'lain( and in&era*&in( /i&h &he Buman-om'u&er @n&er!a*e 5B@6# The mi*ro*om'u&er is *onne*&ed &o a rin&ed ir*ui& )oard 5)6 &ha& *on&ains &he mi*ro*on&roller as /ell as &he s&e''er mo&or dri,er *ir*ui&s on i& !or ea*h o! &he a+is mo&ors# This *onne*&ion is do/n ,ia &he 2?-'in ")-2? arallel or&# A o/er Su''l &akes mains 'o/er !rom &he 220-,ol& A 5=MS6 'o/er sour*e and *on,er&s i& in&o a 24-,ol& " *urren& !or 'o/erin( &he ) as /ell as &he A+is Mo&ors bein( *on&rolled &hrou(h i&# 44
The ) re*ei,es one in'u& !rom &he mi*ro*om'u&er as men&ioned abo,e a 'o/er in'u& !rom &he " 'o/er su''l and *on&rols &he &/o a+is s&e''er mo&ors ,ia 4 /ires ea*h in bi'olar mode# The ) also *on&ains a rela s/i&*h &ha& *on&rols &he &o((lin( o! &he s'indle mo&or# Ano&her mains 'o/er sour*e is used &o 'o/er &he ariable Frequen* "ri,e 5F"6 &ha& dri,es &he hi(h-'o/ered S'indle Mo&or# The =M o! &he s'indle is ,aried inde'enden&l &hrou(h a 'o&en&iome&er knob on &he F"#
2*1 Sot7ar! Ov!rvi!7 a#d de,elo'ed b .e/!an(led
Figure-: 1& 'creenshot sho!ing Mach &s stoc8 interace
4!
The main reason &his /as *hose is be*ause o! i&s !ree-/are as /ell as o'en-sour*e na&ure# )ein( !ree/are mean& &ha& i& qui&e li&erall didnK& *os& us a& all &o use &his so!&/are# "ue &o bein( o'en-sour*e /e ha,e a**ess &o i&s sour*e *ode /hi*h /e in&er're&ed and learned and &hen s&reamlined &o ada'& &o our ma*hineKs !un*&ions and hard/are# @n i&s ori(inal !orm &he *ode /as a''ro+ima&el ?200 lines o! *ode /ri&&en in &he QQ 'ro(rammin( lan(ua(e# A!&er s&reamlinin( and remo,in( irrele,an& !un*&ions 'er&ainin( &o millin( ;"M ma*hines e&*# /e brou(h& &he *ode do/n &o onl abou& 100 lines o! *ode /hi*h in*luded onl our desired *ommand se& !or millin( ma*hine o'era&ions# Ma*h > /as also modi!ied &o /ork /i&h our o/n B@#
4
CHA)TER . Co#clusio# $i&h &he in*reasin( demand !or small s*ale hi(h 're*ision 'ar&s in ,arious indus&ries &he marke& !or small s*ale ma*hine &ools has (ro/n subs&an&iall# Gsin( small ma*hine &ools &o !abri*a&e small s*ale 'ar&s *an 'ro,ide bo&h !le+ibili& and e!!i*ien* in manu!a*&urin( a''roa*hes and redu*e *a'i&al *os& /hi*h is bene!i*ial !or small business o/ners and hobbis&s# @n &his re'or& a small s*ale &hree a+is . millin( ma*hine is desi(ned and analzed under ,er limi&ed bud(e& o! 2000 GS"# "urin( &he s&ru*&ure desi(n s&a(e ,arious *ommon s&ru*&ure !rames are e+'lored and analzed# The mos& sui&able s&ru*&ure !rame &he o'en !rame ,er&i*al &'e s&ru*&ure is *hosen# ri&i*al *om'onen&s su*h as linear (uides mo&ors and en*oders are sele*&ed amon( !e/ di!!eren& o'&ions# The bes& ,alue *om'onen&s are sele*&ed &o a**ommoda&e s&i!!ness requiremen&s and bud(e& *ons&rain&s# The issues o! assemblin( me*hani*al *om'onen&s and emer(in( ele*&ri*al 'ar&s in&o me*hani*al s&ru*&ure are all /ell *onsidered# A 'ro&o&'e ma*hine is assembled in &he lab and "el&a TauUs GMA : is used as mo&ion *on&roller o! &he ma*hine# The de&ailed s&e's o! ho/ &o se&u' and *on!i(urin( &he : is des*ribed in *ha'&er ?# An a&&em'& &o make a ser,o *on&roller 'ar&i*ularl !or &his ma*hine is also *ondu*&ed# The *om'le&ed ma*hine is &es&ed usin( &hree di!!eren& &e*hniques i#e# sur!a*e &es&in( 'er'endi*ulari& &es&in( and *ir*ular &es&in(# The 'ossible error sour*es are de&ermined# The 'ro&o&'e ma*hine has been used &o *rea&e se,eral 'ar&s alread# "ue &o ina**ura* o! &he ma*hine bod 'ar&s and rou(h assemblin( &he ma*hine !ails &o a*hie,e &he desired 're*ision and re'ea&abili& le,el# Bo/e,er i& is s&ill su!!i*ien& &o *rea&e small !ea&ures su*h as le&&ers and (ra'hs /i&h sizes less &han 1*m# A ne/ desi(n is *rea&ed a!&er e,alua&in( &his 'ro&o&'e /i&h !ea&ures o! *alibra&ion and ease o! assemblin(# This /ill *er&ainl hel' &o a*hie,e &he desired *hara*&eris&i*s /i&h &he same amoun& o! bud(e&#
4%
.*- Futur! studi!s The !u&ure s&udies hea,il rel on &he desi(n o! mo&ion *on&roller# @n order &o *u& *os& a mo&ion *on&roller mus& be desi(ned and !abri*a&ed b oursel,es# This requires *rea&in( &he hard/are makin( &he *onne*&ion /ri&in( &he ser,o loo' 'ro(ram /ri&in( &he in&er'ola&ion 'ro(ram and *rea&in( &he BM@# @n *ha'&er ? a s*hema&i* !or hard/are board has alread been *rea&ed# The ser,o loo' 'ro(ram has also been done and &es&ed su**ess!ull# The T@ MS4>0 mi*ro*on&roller *an no/ read 'ulses and a**umula&e 'ulses as re!eren*e in'u&# @& *an read &he en*oder si(nal and (enera&e *on&rol si(nal usin( a sim'le @ *on&roller# Bo/e,er &he !un*&ion &o &une @ (ain in real &ime is e& &o be *rea&ed# Arduino G.> board has been used &o run &he rbl mo&ion *on&rol !irm/are# Bo/e,er &here is s&ill la*k o! a BM@ !or &his !irm/are &o allo/ more user !riendl o'era&ion# The BM@ s&ill needs &o be *rea&ed# The bes& 'ossible solu&ion is usin( =as'berr i as &he L &erminal o! &he *on&roller and usin( a &ou*hs*reen as &he in&er!a*e# This allo/s &he /hole *on&roller &o be made /i&hin a !e/ square-in*hes bo+# Sin*e =as'berr i has i&s o/n embedded :inu+ S &he user *an easil &rans!er ma*hine *ode !ile in&o &he ss&em usin( a GS) dri,e# =as'berr i *an &hen s&ream &he ma*hine *ode in&o Arduino &hrou(h ano&her GS) 'or& easil# Ano&her &hin( &ha& *an be done in &he !u&ure is o'&imiza&ion o! &he !abri*a&ion 'ro*ess !or mass 'rodu*&ion# The *om'onen&s o! &he ma*hine should be ma*hined usin( &he *hea'es& manu!a*&urin( 'ro*ess 'ossible# The main !rame should be be&&er o'&imized !or *as&in(# Ma*hine &es&in( should be *ondu*&ed in a more a**ura&e manner /i&h be&&er equi'men& and be&&er me&hodolo(# Then &he a*&ual number o! 're*ision and re'ea&abili& *an be de&ermined#
48
REFERENCES 516 7enhabib 7eno. 92((3:. Manu'acturing+ &esign ;roduction ,utoation and ;M,"2 so't-are re'erence anual. 536 &elta )au &ata Syste ;M,"2 So't-are re'erence anual 8. &elta )au &ata Syste ,SM >---.otioncontrolonline.org>i4a>$ages>indeD.c'E$ageidF3(1 14. Machinist.org. )he >achinist.org>uncategoried>the@invention@o'@cnc@achining 1!. Mat/eb. 92(((:. ,luinu 2(24@)8!1. 'ro htt$+>>---.at-eb.co>search>&ataSheet.as$DEMatG?<&Fa4(2e2'e!4 8d331e33!1cc2%!8 1. Ogata Aatsuhiko. 92(1(:. Modern "ontrol ngineering+ ;earson. 1%. Slocu ,leDander . 912:. ;recision achine design+ ;rentice@all. 18. =oshii )akeuchi Aiyoshi Sa-ada )oshio Sata. 91!:. "o$uter ,ided ?rtra@;recision Micro@Maching o' Metallic Materials. <
A))ENDI3 A Calculati#$ t"! Tor9u!
The required &orque de'ends u'on &he &'e o! 'o/er s*re/ bein( used# The AM; &hread are mos& *ommonl used ho/e,er &he are ,er ra'idl bein( re'la*e b ball lead s*re/s bu& here a sin(le s&ar& AM; &hread ha,e been *hoosen &o /ork ou& &he &orque requiremen&# As &he aim is &o *al*ula&e &he mo&or 'o/er and i&s required &orque a& &he ou&'u& o! &he (ear bo+ &here!ore &he *ase *onsidered shall onl be /hen &he load a*&in( on &he lead s*re/ is ma+imum i#e# /hen &he mo&ion or !eed is in &he dire*&ion o! *u&&in(# onsiderin( sin(le s&ar& AM; &hread s*re/C &he asso*ia&ed dimensions o! &he lead s*re/ i#e# i&s 'i&*h diame&er &hread an(les *an be ob&ained !rom ,arious desi(n handbooks a**ordin( &o &heir loadin( *a'a*i&# An e+a((era&ed ,ie/ o! a square &hread is sho/n in &he Fi(ure-E-2#>9# For &he deri,a&ion o! &he loads on &his &hread *onsider a sim'le square &hread and un/ound i&# The !or*es on &he &hread are as !ollo/sE
Fi$ur!=: = +*01 E>a$$!rat!d vi!7 o a s9uar! t"r!ad
) resol,in( &he !or*e ,e*&ors alon( &he in*line &he !ollo/in( rela&ion is ob&ained !or square &hreadC
! O !un*&ional !or*e
As
.O .ormal !or*e
&here!ore
$here O o/erR For*e
! O Fun*&ional !or*e . O .e/&on
W O :ead An(le : OX
To (e& &he required !or*e !or &he AM; &hread &he onl di!!eren*e is &he &hread an(le# This &hread an(le /ill *ause an in*rease in &he normal !or*e and hen*e onl &he !ri*&ional !or*e /ill be in*reased# For &he square &hread &he !or*es labeled : and . in &he dia(ram belo/ are equal bu& in *ase o! AM; &hread : is onl a *om'onen& o! .# This is sho/n in &he Fi(ure-E belo/#
Fi$ur!=: = +*1,: Forc! co6(o#!#ts or s9uar! a#d ACME t"r!ad
To ob&ain &he load !or &he &a'ered &hread &he !ri*&ion in*reases /i&h &he &hread an(le 2Y# 2Y is zero in *ase o! square &hread# Thus &he !ri*&ion 'arame&ers /ill in*rease as in *ase o! (uide /as and /ill be di,ided b cos α &o ob&ain &he a*&ual ,alue o!
# @n &he *ase o!
AM; &hread &he &hread an(le 2Y O 290 &here!ore &he required load !or &he AM; &hread *an be *al*ula&ed asE
@n order &o ob&ain a rela&ion !or Torque 5 radius o! &he lead s*re/
6 mul&i'l &he required !or*e
5.-m6
/i&h &he
This is &he !inal rela&ion &o ob&ain required &orque &o dri,e &he load on &he 'o/er s*re/s# @& is kno/n b &he .e/&onKs la/s &ha& a*&ion has an equal and o''osi&e rea*&ion# Ben*e &o dri,e &he load !or/ard an equi,alen& !or*e /ill be a''lied ba*k in&o &he lead s*re/# @& is sho/n as &he rea*&ions in &he Fi(ure-E belo/E
Fi$ur!=: =+*1-: R!actio# orc!s at t"! collar
enerall a *ollar is 'la*ed a& &he base o! &he lead s*re/ &o &ake &he rea*&ions# This *ollar also e+hibi&s a !ri*&ional !or*e /hi*h o''oses &he &orque a''lied# There!ore &he &orque /hi*h is required &o o,er*ome &he !ri*&ion o! &he *ollar has &o be added &o &he *ollar ha,in( a mean diame&er o! !ri*&ion is
OX
Ben*e &he &o&al &orque required be*omesC
T r =
dm 2
×
L ( µπ d m secα + l )
(π d m
−
µsecαl )
L µc
+
dc 2
#onsiderin(
&he &orque needed &o o,er*ome &he *ollar
A))ENDI3 B Str!ss A#alysis )elo/ are &he resul&s o! &he s&ru*&ural anal0sis o! > ma4or *om'onen&s /hi*h are bearin(2 (uide /a0s and side 'la&es# The resul&s in*lude bo&h &he de!orma&ion and &he 1on Mises s&ress dis&ribu&ion o,er &he *om'onen&s# For &he bearin( bo&h &he ma+imum de!orma&ion and s&ress lies on &he inner rin( as &he ma+imum load also a''lies in &he radiall0 ou&/ard dire*&ion# As !or &he (uide /a0s &he ma+imum &ensile s&ress lies a& &he bo&&om due &o bendin( s&resses2 hen*e &he ma+imum de!orma&ion also lies a& &he bo&&om# $hereas &he ma+imum *om'ression s&ress lies a& &he &o' /hi*h is a''ro+ima&el0 equal in ma(ni&ude /i&h &he &ensile one# The side 'la&es2 on &he o&her hand2 has ma+imum de!orma&ion a& &he bo&&om /here i& is a&&a*hed &o &he base# The ma+imum s&ress2 ho/e,er2 e+is&s a& &he lo*a&ion /here &he (uide /a0s 'asses &hrou(h i&#
Figure-: 1 eor#ation - *earing
Figure-: 1+ 'tress $istriution - *earing
Figure-: 1, eor#ation - 9ui$e !ays
Figure-: 1 'tress istriution - 9ui$e ! ays
Figure-: 13 eor#ation - si$e plates
Figure-: 14 'tress $istriution - 'i$e plates
