Nguyen Dang Binh Tap chf KHOA HQC & CONG NGHE 104(04): 165-167
CHQN CAU TRUC T 6 I UtJ CUA MODUL SAN XUAT TV" DQNG LINH HOAT
Nguyen D3ng Binh Truang Dgi hpc Ky! ihu^t Cang nghi?p - DH Thai Nguyen TOM TAT
H? thong san xudt linh hoat (Flexible Manufacturing System - FMS) v^ Modul shn xuat tu dpng linh hoELt (Flexible Manufacturing Modular - FMM) ra db'x \i mpt cupc cdch mang vd Id mpt thdnh tyu quan trong trong khoa hoc ky thuat. Bdi bdo gi6i thi^u m^t phuang phdp xdc dinh cdu true t6i uu Clia FMM dp dung khi thiet ke, xay d\mg mpt FMM mdi hoSc t6i uu hieu qua ldm viec ciia mot FMM c6 sin, ho^it dpng dpe Idp ho§c hoat dpng trong mot FMS
Tir kh6a: He thong sdn xual linh hoal, modul sdn xudt lu- dgng linh hogt DAT VAN DE
Hieu qua hoat dpng ciia mpt h? thong san xuit tu dpng linh hoat (Flexible Manufacturing System - FMS) noi chung va modul san xuat tir dpng linh hoat (Flexible Manufacturing Modul - FMM) noi rieng phu thuoc rat nhieu cau triic ciia FMM. "Cau true toi uu" a day vai nghTa la sir thich irng lam viec mpt each toi uu giiia robot va cac may gia cong CNC. cAu triic ciia mpt FMM duac thiet ke dira tren dac diem cua san pham dugc gia cong tren FMM (chi tiet gia cong), loai nguyen cong gia cong, chung loai va so lupng robot, chiing loai va so lupng may CNC Gai bai toan toi uu cau triic ciia mot FMM la di tinh toan so luong toi uu ciia robot va ciia may CNC c4u thanh nen FMM. Bai toan ciing dugc giai han vai FMM co 1 robot va n may CNC.
GIAI BAI TOAN TOI l/U CAU TRUC CUA FMM
Khi tinh toan thiet kS dS co mpt FMM hoat dgng hieu qua, thuang dugc tien hanh qua cac biroc sau: Xac djnh san phSm can dupe gia cong tren FMM; tren ca sa ty thuyet gia cong nhom, lap cac nhom chi tiet gia cong; xay dung chi tiet gia cong dien hinh; lap quy trinh cong nghe gia cong va chpn chg dp cong nghe (chg dg cat, dung cu cat...) gia cong chi tiet dien hinh; chgn robot va cac may CNC (Cac may CNC co th6 gi6ng nhau hoac khac nhau.
Bai toan cu thS a day cung dugc gioi han la cac may CNC giong nhau); xay dung mo hinh
Tet- 0913 286661
toan toi uu de chgn cau triic toi uu cho FMM;
ngoai ra, neu FMM hogt dgng trong FMS thi CO the tinh so lugng FMM can thiet hoat dpng de thuc hien nhiem vu san xuat theo ke hoach.
Trong cac npi dung tren, bai toan tap trung vao xay dung mo hinh toan toi uu de lua chon c4u true toi uu cua FMM. Cu the la tren ca so mgt FMM da dugc so bp lira chpn, ta chgn s6 lupng may CNC can thiet de co hieu qua nhat khi gia cong cac san pham da xac dinh; hoac la vai mgt FMM co san hoat dpng dgc lap hay hoat dgng trong mpt FMS, cSn xac djnh phuang thiic lam viec toi iru ciia FMM sao cho hieu qua hoat dgng ciia no cao nhat.
De xac dinh mo hinh toi uu, ta chpn ham muc tieu la chi phi gia cong nho nhat, ky hieu la Q.
Ham muc tieu Q dirge xac dinh nhu sau:
Trong do:
C,> - Gia ciia FMM tinh tren 1 gia gia cong;
C.-C^.+C^.=C,,+ZC...,. (2) C/v - Gia cua Robot tinh tt^n 1 gia gia cong;
CpM - Gia thanh cita may thu i tinh tren 1 gio gia cong;
« - so lugng may CNC ciia FMM;
5 - G i a mot FMM; S duac tinh nhu sau:
5 = S,+XS„, (3) Sr - Gia R'obot,
Su, - Gia may CNC tliir i;
En - He s6 SIX dung cCia FMM, dirge tinli tlieo [1];
165
Nguyin DSng Binh T9P chi KHOA HQC & C 6 N G NGHe 104(04): 165-167 Tp - Thirl gian ke ho^ch Ihm vi?c cua FMM;
T,k - G\& Clia dyng cy cSt thur I tinh trSn I gi6 gia cong;
Cutk - Gii cua dyng cy cSt thu" I;
A„ - Miic dp (%) tham gia gia c6ng ciia dyng cy cat thu I khi gia cong lo^t chi tiet thu k;
(„pk - Thdi gian trung binh m6i lan di^u chinh FMM;
Z.* - So lirgng t6ng c6c logi dyng cy tham gia gia cong logt chi tiet thii k;
Ni - So lugng chi tiet trong lo^t chi ti^t thii k;
Nk - Nang xuat ciia FMM khi gia c6ng logt chi tiet thii k;
Ok - So nhom chi tiet trong loat chi tiet thii k;
Tir(l), (2) v^(3)tac6ham myc tieu sau:
Tinh den cac dieu ki?n han che ve kJ thugt va kinh te nhu h? so chat tai cua robot, may CNC va h? s6 tinh den hi?u qua t6i thieu cua FMM, ta CO mo hinh toan toi uu ve cau true FMM nhu sau:
Trong do:
— A / . J.
KHI- - H^ so chat tai trung binh ciia FMM gdm n may CNC;
^WAT • ^ ^ ^° ^^^^ *^' ^^^ ^^y *--^^ ^^ 8 ' ^ cong loat chi ti8t k;
KHI- - H? so chat tai trung binh ciia Robot lam vi?c trong FMM vai n may CNC;
K'^^ - H? so chat tai ciia Robot doi vai moi may CNC;
K^ - H? s6 chat tai dinh miic (toi thi6u) Clia may CNC;
\K'/,J - He so chat tai dinh miic (t6i thi^u) cua Robot;
Ff^^ - Nfing xuat ciia FMM khi gia cong loat chl tiet thu k;
K - So logt chi tiet dirge gia c6ng tren FMM theo ke hogch.
N^u coi chi phi dyng cy cfit dugfc coi la nhu nhau d6i vdi t^t ca cac phucmg dn thi tii (5) ta c6 mo hinh tofin toi uu sau:
Trong thyc te, thong thudng cac FMM co cau triic gom 1 (hofic 2) robot va n may CNC giong nhau. Vi vgy, Mo hinh toan toi uu (6) se CO dgng don gian hon sau:
(7)
Giai cac mo hinh toan toi uu (5), (6), (7) ta tim dugc so lugng may CNC can thiet trong cau tnic ciia mpt FMM hoat dgng dgc lap hogc hogt dpng trong mpt FMS.
KET LUAN:
1. Trong thyc te. cac FMM thucmg la co cac may CNC giong nhau. Vi vgy, chu yeu mo hinh toan toi uu (7) dugc ap dung khi tinh toan cau true FMM.
2. Bai toan toi uu cau true ciia FMM con dugc ap dytig d8 t6i uu phucmg thtic lam viec Clia mpt FMM da co san khi hogt dgng doc lgp, cung nhu khi hogt dgng trong mpt FMS.
Luc do bai toan trcr tiianh "Xac djnh so maj;
trong FMM lam viec d^ co hi^u qua kinh te nhat". Bai toan nay co y nghTa kinh te ky thugt rat lem, vi neu ta xac dinh dugc so may lam vi?c t6\ uu < n, thi trong khi gia c6ng, mpt so may khdng gia c6ng c6 the dugc bao duong hogc dugc dieu chinh lai de gia c6ng cac logt chi tik tiep theo.
3. Giai cac mo hinh toin toi iru tren dugc thuc hi?n nhd cac chuang trinh phan mem may tinh CO sin.
Nguyin DSng Binh Tsp chl KHOA HQC & C 6 N G N G H $ 104(04): 165 -167 TAI LIEU THAM K H A O [3]. Nguyin DSng Binh. "X4c ilinh hf so su dung [1], Nguyin Dang Binh, (1997), "Xic djnh cic cua modul sin xak linh hojl (FMM) trong h?
thang s6 co bin cua modul sin xukt tv d^ng trong thing sin xuit linh host FMS tren co sd hj thong h^ th6ng CAC/CAM", Th6ng bio khoa hgc cila CAD/CAM. Tsp chl Khoa hgc vi Cdng nghe, E)?i cic truimg d^i hgc, Bg Giio diic vi Dio 190. hgc Thii NguySn, s6 1(37), 2/2006.
[2], U.Rembold and B.O.Nnaji, (1994), Computer [4]. Binh Tien Long vi mgt so tic gii, (1998), intergrated manufacturing and engineering, "C6ng ngh? CAD/CAM CIMATION", Nhi xuat Addison Wesley Publishing company. bin Khoa hgc vi Ky thu§t. Hi n^i.
SUMMARY
SELECTION OF THE OPTIMAL STHUTURE OF FLEXIBLE MANUFACTURING MODUL
Nguyen Dang Binh' College ofTechnology - TNV Creating Flexible Manufacturing System (FMS) and flexible Manufacturing Modul (FMM) is a revolution and an important achievement in science and technology. This paper presents a method for determining the optimal structure of FMM applied when designing and building a new FMM or optimizing working efficiency of the FMM already existing and operating independently or in a FMS.
Keywords: Flexible Manufachirlng System, flexible Manufacluring Modul
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