Cap chinh xac la kha nang dat dugc muc dp diing, hay ndi each khac la sai lech Idn nhat cua chuyen dpng quay hoac dich chuydn giOa hai diem trong pham vi khong gian lam vice ciia may.. N
Trang 1NGHIEN CU'U - TRAO D O I
^NGHIEN CL L ANH HUONG CL A BO CHINH XAC
KHOrp DEN SAI LECH VI TRI DO SQfl CUA HE T H O N G
DO SOI TLT D O N G M\\ s g i C O N
A RESEARCH ON EFFECT OF JOINT ACCURACY ON ERROR
OF DOFFING POSITION OF RING SPINNING'S AUTODOFFER
Nguven Xuan C h u n g ' , Hoang \ an G g t \ Nguven Doan V'
'Trudng Dai hpc Cong nghidp Ha Npi -Vien Nghidn cuu Ca khi Bd Cdng Thuang
'Trudng Dai hpc Bach khoa Ha Ndi TOM TAT
Chdt luong cua he thong do sai tu dpng duoc ddnh gid hdng khd ndng ldm viec on djnh, Idu ddi d che dp ldm viec tdi iru De ddm bdo duoc chdi lupng ctia he thdng cdn dam bdo dp chinh xdc dgng hpc cua he co cdu co khi (cu the la dp chinh xdc vl tri cua ddm soi) Bdi bdo ndy trinh bdy mot nghien cuu thuc nghiem do xir ly vd ddnh gid dnh hudng cua dp chinh xdc cdc kh&p ciia ca cdu phdng vd co cdu khdng gian cua he thdng do soi tu dpng mdy sai con den do chinh xdc vi tri cua ddm sai bdng phuang phdp thong ke thdng qua cdc chi tieu ve chinh xdc lap a che dp lam viec thuc le voi khe hd khdp vd tdi trpng khac nhau
Tir khoa: Dp chinh xdc khdp: Do sol tu dpng: Sai lech vi tri do soi; Mdy sai con
ABSTRACT
The quality of an auto-doffer is estimated based on its consistency and long-life in optimized conditions In order to insure the quality of the svstem it is necessary lo remain the kinematic accuracy of the mechanism system, especially the position accuracy ofdoffer bar This article presents an experimental research on the effect of the accuracy of joints in planar and partial mechanism system of the auto-doffer system on the position accurac\ of doffer baf based on two parameters, the repeated accuracy in practical condition and the joint clearance in dijferent load modes
Kevwords; Joint accuracy: Autodoffer: Dofling position deviation: Ring spinning
frame
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Trang 2NGHIEN CU'U-TRAO D O I
I.DATVVN DE
He thdng do sgi tu ddng may sgi con
lam nhidm v u do blip spi da quan day va nap
ldi spi rong vao true chinh may spi con [I]
Trong so cac chi tidu chat lupng hoat dpng
ciia he thdng, chi tieu chinh xac v i tri do sgi
la chi tidu quan trgng nhat Cd hai yeu to
thudng dugc su dung dd danh gia linh chinh
xac CLia mpt he thdng ca khi la cap chinh xac
va dp chinh xac
Cap chinh xac la kha nang dat dugc
muc dp diing, hay ndi each khac la sai lech
Idn nhat cua chuyen dpng quay hoac dich
chuydn giOa hai diem trong pham vi khong
gian lam vice ciia may Kha nang lap (dp
chinh xac) la kha nang nhae lai diing nhidu
lan, hay sai sd giira mpt sd lan thuc hien djch
chuydn thanh cdng ddn cimg mpt vi tri Ddi
vdi h? dd spi tu dgng, dp chinh xac v j tri cita
lam lay gap so vdi tam cua true chinh/chdt
ciia may spi con la ehi tieu quan trpng nhat
phan anh dp chinh xac vi tri dd sgi Dp chinh
\ac vj tri a day, dugc hicu la xac suat vj tri
tay gap dat dugc vi tri chinh xac trong qua
trinh hoat ddng
Bai bao [2], da thidt lap dupc md hinh
ly thuyet ciia sai sd v i tri ciia co cSu nang ha
va quay lat Nghidn ciiu thyc nghiem sedua
ra qui luat phan bd cung nhu tim dugc cac
tham sd thdng kd cua dp chinh \ac vi tri ciia
he thong do spi ty dpng may sgi con Hidn
cd nhidu cdng trinh nghien cuu vd sai sd vj
tri cua mav cdng cu va robot cong nghiep
Bai bao [3] nghidn cim sai lech ITnh va dp
chinh xac ciia may cdng cu C NC sir dung
he thdng do lazer va phep do lap dd tim cac
dac trung vd dp chinh xac mav Bai bao [4]
da dua ra mdt phuong phap ly thuyet dd tinh loan dp chinh xac vi tri tay ciia robot cdng nghidp Tuy nhien, cac cdng trinh chu veu nham danh gia do chinh xac cua thiet bj ma khdng neu dugc cu thd bang thyc nghipm cac anh hudng ciia chd dp lam v ipc cung nhu
dp chinh xac chd tao
Bai bao nav dua ra mpt phuang phap thyc nghidm do xir ly ket qua va danh gia dupc dp chinh xac v i tri dd sgi Npi dung tap trung vao thidt ke che tao md hinh thi nghidm cung nhu he thdng do ludng sai I^ch
VI tri do spi Thi nghiem do ludng dp chinh xac (kha nang lap) \i tri thyc hien d hai che dp: Lap ghep cac khdp vdi khe hd nhd va khdng mang tai va che dp lap kem chinh xac han vdi tai trpng tuong duang vdi tai trpng lam vide cua he thdng thyc
2 TRANG THIET HI \ A TRINH TV DO LUOfNG THL C NGHIEM
2.1 Trang thiet hi nghien cihi
Md hinh thi nghidm dugc thidt kd theo mpt mo dun cua he thong do sgi tu
dgng may sgi con Be dap ung dupc ydu cau
dong dang va tuang ty, md hinh dugc thidt
ke va chd tao theo ty le 1:1 Cac chd dp hoat dpng: Hanh trinh van tdc, tai trpng cua md hinh tuang ty nhu cac che dp hogt dpng ciia
he thdng thyc
a) He thong truyen ddn co khi:
Dya theo he thong dd sgi tu dpng may spi con, la xav dyng so dd dpng hpc cua co cau quay-lai va nang - ha, nhu sau (hinh 1 a vab):
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'J-i ~ ^
Hinh 1 Sa do dpng hoc ciia ca cdu quay-ldt (a) \dndng- hg (b)
b) He thdng dieu khien vd he thong do:
Chuydn dpng quay-lat: Bat dau tir
dpng ca dien 1, qua bp truydn dai rang 2 den
bp truyen vit me-dai dc 3 lam true 4 chuvcn
dpng tinh ticn Chuyen dpng linh tidn cua
true 4 lam quay lac khdp chir L 5 quanh gdi
dd 6 qua tay don 7, khdp cau 8 va thanh
truyen 9 quay quanh tam mang dam spi
quay lat
Chuyen dpng nang ha tir dpng co
dien 11 qua bo truyen dai tdi ca cau vit
me-dai dc 13 lam true chinh 14 tjnh tidn Chuydn
dpng tinh tidn cua true chinh 14 tam thanh
truydn 16 va 15 tao chuvcn dpng nang (ha
dam sgi - thanh ga k?p cupn chi)
Nguyen ly hoat ddng ciia he thdng didu khidn (md ta tren ca sd chuc nang ciia
md hinh)
Hinh 2 Sa do khdi he ihdng dieu khiin:
Serw Driver • BQ dieu khicn d(>ng iir icno
CTHT - cang tdc hanh Irinh, CBQ (t.41 - cam bien tfuang
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Trang 4NGHlfN CU'U-TRAO D 6 |
Trdn hinh 2 he thdng didu khien
gdm cd: \1a> tinh dupc kdt ndi vdi PLC
thdng qua chuan truyen thdng RS 232 Mav
tinh ra cac ldnh didu khien van tdc, vi tri
tdi PLC PLC thyc hien qua trinh tinh loan,
cap xung dieu khicn van tdc va vi tri tdi cac
dpng CO servo 1 v a 2 dd thyc hien qua trinh
nang ha va quay lat ciia he thdng ca khi
Bdn cdng tac hanh trinh dupc sii dung de
dam bao an toan gidi han chuydn dpng ciia
he thong co khi
Dpng CO servo ciia hang Delta do
cd cac dac tinh: Kha nang dieu khien v i tri
vdng quay chinh xac encoder cd dp phan
giai cao 17bit (160.000 xung/vong) kha
nang dieu khien tdc dp v a md men dn dinh,
tich hop ca ba chd dp dieu khidn vi tri, tdc
dp va mo men
Vi tri cua dam sgi dupc do bang 2
cam bidn lazer ket qua do tir cac cam bidn
dugc thu thap bdi bd thu thap dii lieu va
diif Ii?u truyen ve mav tinh thdng qua cdng
USB Cam bidn laser do khoang each sir
dyng nguydn Iv tam giac dac phu hpp vdi
ddi tugng do {\\ tri cua dam sgi), cd thd
dap ung dugc ydu ciu do dp chinh \ac vi tri
dam spi Chpn cam bidn laze 2X-LD40 cua
hang Omron cd cac thdng sd ky thuat cua
cam bien nhu sau: Khoang each do: 40 mm
±10mm; dp phan giai: 2 ^m; tdcddiay mSu:
150 MS
H inh 3 la so do khdi ciia he thdng do
su dung dau do khoang each lazer cua hang
Omron
- Khdi cam bidn cd chuc nang thu
thap tin hidu khoang each bang tia laser va
giri dir lieu dang didn ap hoac cirang dp ddng didn ra ngoai bd phan thu thap
- Khoi ADC cd chiic nang chuydn cac tin hidu khoang each dudi dang didn ap hoac cudng dp dong didn thanh tin hicu sd
de cd the ghep noi va thu thap dii lieu vdi
may tinh Yeu cau bd \DC phai cd dp phan
giai du Idn dd giam sai sd khi thyc hidn phep do
Hinh 3 Sa do khdi he thdng do
De do dupc nhicu dir lieu cimg liic
va truydn ve may tinh, tac gia da lua chpn
bd thu thap du lieu USB I208FS cua hang Measurement Computing:
Tir sa dd khdi he thong, ta cd the tinh toan va lap chuang trinh do theo trinh
ty sau:
+ Tinh loan sai sd thyc td tir thidt bi
do V a va bp chuyen ddi ADC
+ Hieu chuan ciia cam bidn va tin hidu chuydn ddi
+ Lap trinh giao didn thu thap dii lieu, ve bidu dotryc quan va luu dO lieu dudi dang bang sd
Sir dung phan mem DASVLab cai dat trong may tinh dd thidt kd giao didn thu thap dii lieu, tinh toan chuyen ddi do ludng, ket xuat va luu trir du- li?u do vj tri dam sai
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Luu dd thuat toan dpc ghi diir lieu d djnh
dang ACIl nhu trdn hinh 5
2.2 Trinh tu- thirc hien:
Nghien cCm thyc nghidm dp chinh
xac vi tri do spi cua he thdng do spi tu dpng
may spi con theo cac budc: Mav dugc lap
trinh dd he thdng mang dam sgi chuydn
dgng tir vi tri 1 (hinh 4) (la vi tri bang tai
biip sgi) chuydn ddng quay lat 13o sau do
chuydn dpng nang den chieu caocan thidL
tidp tyc quay lat v ao (v i tri sd 7), ha xudng vi
tri sd 5, dimg !gi Liic nay, h? thdng do vj tri
dam spi boat dpng, lay kdt qua giri vc may
tinh Sau dd, he thdng lai nang dam sgi len
vj tri sd 6 va chuyen dpng ngupc lai vd vj tri
sd 1 Chu trinh hoat dpng va do vj tri nay lap
Igi bang sd lan do tinh loan (xem phan sau)
thdi gian nhat dinh (20 ms), tai v i Xri do (vi
tri tuang ling vdi sd 5 d hinh 1) v a he thdng
do se hoat ddng, lay mau dir li^u v a ghi v ao may tinh Chd dp hoat ddng ciia mo hinh phai dam bao tuang duang vdi chd dp hoat dpng cua he thdng thyc
Didm dich dupc chpn la diem dam sgi dimg tuang ung vdi diem tam cua tav gap blip sgi triing vdi tam cua true chinh may sgi con (diem tuang ling vdi vj tri 5 d hinh 4)
Cai dat he thdng do nham muc dich
do khoang each tuang ddi giua dau do va dam sgi tai vi tri dam spi img vdi \ i tri tam ta> gap trimg vdi tam true chinh ciia may spi con (hinh 6) Du lieu vi tri dupe may tinh ghi lai d dinh dang ACII va sau ciing la xu
Iv V a danh gia ket qua do
cin tinh loan so lan do can thidt 0 day, ta tinh toan sd lin do theo phuang phap mau kep Trudc tien, didu tra mot mau so bp
kich t h u d c m > 2 , H\={X^,X,, X,„)x\m
phuang sai mau so bd:
Hinh 4 So do I at dii}m di'nig cua ddu kep biip spi:
11 yitnnhabupsp: -t ' " " ' ' ' ! ' • " " I'l^ *•/'
h Shuikfi'ildiisnagialntngguin
JI i'hi' kip ''I K<!' '•I'/' "•'" iren irvc chinh 6 ~) Cha
DSm sgi thyc hien chuyen dpng tuan
ty nane quay Igt va dimg lai mdt khoang
( I )
vdi ^ = — / X^
Sau do, lap mau thu hai cd kich thudc:
n~m: (C, = ( X , \ ,„^,, A",,)
Kich thudc mau can lim la:
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Ap dung cong thuc (2) \ ITI sai so cho phep ciia phep do la 0,05 mm dp tin cay 9?" 0 tra bang Student voi m=5 ta co:
tl 571
Ta cd:
Hinh 5 Luu do dpc dir lieu
Trong trudng hgp linh toan sd lin do
cho phep do lap cua md hinh dd sgi, ta chpn
sa bp m = 5
Ta cd cac gia tri do nhu sau:
0 0329 ' ;^.2,571 = 33,8426 0,05^
Nhu vay, ta chpn sd lan do n=34
Bdng 1 Gid tri do sa bp
L a n do G i a t r i do
1 -O.O").!
2
3
4
5
-0.19.1 0.064 O.IO."!
0,247
3 THI NGHIEM \ A XL LY KET QUA
THI NGHIEM
Thi nghidm do dp chinh xac vi tri lien hanh qua hai budc Budc 1, sir dung cac
HI
chd dp lap ghep—z"(khe hd khdp 62 pm) khdng tai Budc 2, thay thd chd dp lap ghep tai cac khdp A, B, C M, N, P, Q , bSng chd dp lap ghepl-(khe hd khdp 124 pm) va
dugc:
cd tai trpng (lap trdn dam sgi) vdi gia tri tai Sir dung phuang trinh frdn, ta tim trpngF = 138 V
= 0,0329
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Trinh tu mdi budc dupc thyc hien
nhu sau:
Cam bidn lazer nhan vi yi cua dam
spi tai vi tri dimg va chuydn diJ lieu vi tri qua
card A D vc may tinh Phan mdm Dasyslab
chuydn ddi tin hidu thanh sd (d dang cdt) va
luu thanh tap tin trong may tinh Dir lieu v j
tri dupc lay mau d 20 ms cudi khi co ldnh
dimg va vi tri do dupc lay trung binh coiu
ciia dir lieu ndi trdn Trong trudng hpp da\
kdt qua quan trac cd nhimg gia tri do sai lech
qua Idn, can kiem tra xem do cd phai la sai
sd thd hay khdng.Ndu cd sai sd tho thi phai
loai bd
Dya vao ket qua do trong bang 2 ta
xa> dung dupc dd thi vj tri ciia gia tri trung
binh tai cac diem A va B {hai dau) ciia dam
sgi (bang 3) va ham phan bd (PDF) sai lech
V j tri d i m spi {hinh 8a b c d) Tir cac kdt qua nay, ta cd thd xac dinh dupc dp chinh
\ a c thuc nghiem ciia md hinh dd sgi va tir
dd nitra dugc dp chinh xac vi tri dd spi ciia
he thdng do spi ty ddng may sai con
Hinh 6 Dieu chmh cdc vi tri do cua hi' thdng
do ludng vj tri
Bdng 2 So lieu vj tri ciia ddm sen a 34 Idn do
TT
Khong tai, che dQ
i i p ^
/ 7
Dau 4
1 1 -0,044
-1
3
4
5
6
-s
'
0,024
0,204
0,033
0,049
0,107
-0,060
-0,220
-0,010
Dau B
-0,093
-0,193
0,064
0,103
0,247
0,058
-0,045
-0.013
-0,037
Tai tr^ng
F =138 V,
F9
che do lap /i9 Dau \ ' Diu B -0,150 -0,128 0.065 -0,154
0.019 0.051
O.OSO 0,058
0,061 ' ().()94 -0,163 0,324 0,072 0,067
l O am
-0,0<J1 -0,112 -0,111
TT
18
19
20
21
22
23
24
25
26
K h o n g t a i , c h e d 9
/ 7 Dau A -0.207 -0,069 0,047 0,100 -0,089 0,133 0,105 -0,142 -0,081
Dau B -0,112 -0,150 -0,036
-(I.J2«
-0.(14:
-11.043 -0,063 -0,116 -0,146
Tai trpng
F = 138 V, , F 9 che do ISp Dau A -0,095 0,034 0,138 0,036 -0,150 -0,128 0,065 -0.154
DiuB
-0,194 -0,117 -0,084 0,055 0,019 0,051 0,080 0.058
0,061 ' 0.094 ]
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Trang 8NGHIEN c u u - TRAO DOI
- (1 -0,082
1 -0.189
: 0.063
3 -(1.04"
4 0.0:9
5 -0.1 SS
6 0.0"S
0.053
-0.09:
-0.191
-0.144
-0.045
0.132
-0.143
0.041
0.039
0.005 -0.05S -0.046 -o.4:s 0.13"
0,063 0.361 0.:""
-0.088 -0.111 -0.114 -o.:9s -0.04S
-0,042
-0.050
-0.066
27
28
29
30
31
32
33
34
0,062 0,246 0,177 0,120 0,024 0,049 0,136 0,076
0,040 0,034 0,119 -0,241 0.066 -0.1 S4 0,137 -0,087
-0,163 0,310 0,071 0,067 0.005 -0,058 -0,046 -0,428
0.009
-0,009 1
-0,112 -0,111 -0,088 -0,111 -0,114 -0,298
6 day ta diing phucmg phap do vi tri v a d hai dau cua dam sgi vdi sd Ian do n, sau dd tinh toan cac tham sd thdng ke:
Gia tn trung binh ciia v i tri; -^
Phuang sai cua sai lech v i tri: ^ _
Bang 3 Bdng gid Iri tnmg binh vd do lech chudn
(4)
Ten tham so
Dang lam khit
1 Gia tn trung binh
Phuang sai
Dau A khong tai
Phan bo chuan
0.0I43I6Q
0.0I3^IKr
Dau B khong tai Phan bo chuan
0.0429702
0.015169
Dau \ CO tai
Phan bo clman -0.0037937
0.0318697
Dau B CO tai Phan bo chuan -0.0471056 0.010131
Su dung phan mdm Matlab \u Iv so lieu d bang 2 theo trinh ty: Dpc duf li^u, sii dung img dung Distribution Fitting, chpn mang dir lieu, chia ldp, chpn dang phan bd va kdt xuat dir hdu dd thj Gia tri trung binh, phuang sai ciia phan bd cung nhu cac tham sd ve mau, sai lech dupc kdt xuat Bang 3 la bang gia tri tham sd va dang phan bd lya chpn lam khit Dd thi tren hinh 8a,b,c.d la dd thj mat dp xac suat phan bd vi tri dd spi 0 hai chd dp lip ghep va tai trgng nhu phan trdn da ndi
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c) d)
Hinh 7 Dd thi hdm mat do xdc sudt cua vi tri lap cua ddm spri:
al Do lai ddu A, che dp lap , khdng tdi b) Do tai ddu B che dp lap khong tat
• F9 F9 c) Do tai ddu A che dp lap cd tai d) Do ddu B, che dp lap , cd tdi
h9 h9
Kdt qua do cac thdng sd chinh xac
vj tri cua he thdng ca cau ca khi co the phan
anh dugc anh hudng ciia dp chinh xac ca cau
ca khi Dang dudng cong phan bd cua kdt
qua do gan diing vdi dang dudng cong phan
bd chuan Day cung la mdt trong nhimg tinh
chat quan trpng cua sai sd hinh hpc ciia he
thdng may mdc cd chuydn dpng djnh vi (vi
du nhu may cdng cu) khi anh hudng cua qua
trinh dpng lyc hpc (gia tdc, nhidt, ma sat tai
khdp ddng ) la khdng dang kd
Ddi vdi chd dp lap ( — ) khdng tai
trpng, dang dudng cong phan bo rat gan vdi
phan bd chuan Tuy nhidn, d chd dp lap
F9
( — ) \ a lam v lec cd tai, dudng cong phan
bd bi bidn d^ng, miic dp phan tan tang, I?ch
vd chidu duang ciia true hoanh (lech ve B)
Nhu vav ta thiy ring khe hd khdp cd anh
hudniz gan nhu quyet dinh den dp chinh xac
VI tri dd spi Tuy nhidn, d vdi chd dp lap ghep nay, xac suat sai Idch vi tri cua dam spi vin nim trong gidi han cho phep (±0,2 mm vdi muc tin cay 95%)
4 KKT I T AN Tir npi dung nghidn cim tren ta thay qua trinh thidt kd va chd t^o md hinh cua h? thdng dd sgi ty dpng may sgi con, eung nhu
V lec thidt lap he thdng do ludng va xir ly sd lieu thyc nghiem la mpt phuang phap hieu qua trong vide danh gia dupc dp chinh xac
vi tri dd spi ciia he thdng thdng qua danh gia chi tieu chat lupng la dp chinh xac lap
Vide thay ddi chd dp lap ghep lam thay ddi khe hd cac khdp cua ca cau cung nhu thay ddi tai trpng cdng tac va tidn hanh
do luimg sai lech vi tri, cung cd thd dupc sir dyng cho v idc thidt ke, che tao, khai thac, van hanh, bao tri he thdng do spi ty dpng m:i\ sgi
con va md rong cho cac h? co khi khac •> "
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Trang 10NGHIEN c u u - TRAO e6i
10
11
12
>3
14
15
16
17
-0,082
-0,189
0,063
-0,047
0,029
-0,188
0.0-S
0.053
-0,092
-0,191
-0.144
0,005 -0.05S -0.O46 -0.045 -0,428
0.132
-0.143
0.041
0,039
0,137 0,063 0,361
0,277
-0,08S -0,111 -0,114 -0,298 -0,048 -0,042 -0,050 -0.066
27
28
29
30
31
32
33
34
0,062 0,246 0.177 0,120 0,024 0.049 0,136 0,076
0,040 0,034 0.119 -0J41 0,066 -0,184
0.13 0.087
-0,163 0,310 0,071 0,067 0,005 -0,058 -0,046 -0,428
0.009 -0,009 -0,112 -0,111 -0.088 -0,111 -0,114
-0,298
0 dav ta dimg phuang phap do v i tri v a d hai dau ciia dam spi v di sd Ian do n, sau dd tinh toan cac tham sd thdng kd:
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ISSN 0866 - 7056
TAP CHi CO KHi VIET NAM, Sd 9 nam 2016