Tối ưu hóa kết cấu hệ khung xe di chuyển dọc cầu thang phục vụ cho người khuyết tật

TOI U u HOA KET c A u HE KHUNG XE Dl CHUYEN DOC CAU THANG PHUC VU CHO NGUOfl KHUYET TAT OPTIMIZATION OF THE STRUCTURE PLATFORM OF THE WHEELCHAIR STAIR LIFTING DEVICE FOR THE REHABILITATION PATIENTS Nguyen Minh Tri\ Nguyin Quang HuyS Huynh Quang Huy", Mai Thanh Diln', Tnidng QuSc Thanh' 'Trung tam Thiet ke va Che tao Thift bi mdi (NEPTECH) 'Tnidng Dai hoc Bach Khoa TR H6 Chi Minh T6M TAT Trong bdi bdo ndy, cdc ket cdu dqng khung vd he thdng cd cua xe di chuyen doc cdu t bd mangxe ldn cua cdc nghien ciiu tren tMgidi duac gidi thi$u Viec tinh todn thiet kevd toi Uu ho khung xe bdng phdn mem Hyperworks dUdc thtic hien C^ud trinh mo phong vd tinh todn toi Uu hd dUdc k^tqud thuyet phuc ve khoi lUdng khung gidm 9,1 %, iing sudt ldn nhdt gidm 26,7% vd ddn chuyen vi cUng gidm 28% Cdc dieu diiu kiin ben, vong cho phep vd khoi lUdng dong thdi dUdc mot cdch hieu qud Ttt khoa: Platform Lift; Stair Lifi; Pigita; Thiet bi hd trd Un xudng cdu thang In this paper, we analysed some ofthe mechanism structures based on the current wheelchai lifting devices In this device, the structure of the platform lift was modified and recalculated to stre durability and reduce the material The Hyperworks computer-aided engineering (CAE) software, Engineering Ltd., was usedfor ourfinite elements analysis (EEA) experiments The results showed t mass structure, the maximum stress and the displacement of the platform were reduced 9.1%, 26.7% 28%, respectively In our studies, the stable condition, the allowable deflection and the mass structu optmized simultaneous as an efficient method TAP CHl CO KHl V I £ T NAM, S6 nam 2013 G l l T H I £ U CHUNG Hien nay, vdi sU phdt trien cua ky thuat, da CO nhilu loai phUdng tiln hd trd ngUdi mat kha nang di lai cd the di chuyen sinh ho^t nhU: NgUdi ldn tudi, ngUdi khuylt tat, benh nhan liln quan din cdt sdng dnh hUdng d i n chi dUdi, v.v Mpt phUdng tiln dien hinh Id xe lan NhUng vdi nhflng ban c h l ve ky thudt, ngUdi sfl dung xe lan van gap rat nhieu khd khan di chuyin dia hinh cd cdc ehudng ngai vat nhu cau thang, b^c thim Nhflng chfldng ngai vdt rdt phd biln cdc thdnh phd, cac tda nha, van phong, cong sd, chung cU Vi vay, viec nghiin cflu he thdng ndng chuyen xe lln hoac xudng d nhflng ndi cd ed cau thang bd la can thilt nham giup va hd trd cho ngUdi gid va ngUdi khuyet tat Thdng thudng, sd lUdng ngUdi trp giup nhflng ngUdi ngoi xe lan len hodc xudng doc la tfl mdt den hai ngUdi, cdn de lln hoac xudng cau thang thi phai can tfl hai den bdn ngUdi thudc vao trpng lUdng cua ngUdi ngdi trin xe ldn Hinh trinh bay cac phUdng thflc van chuyen ngUdi thu cdng lln cau thane bd „ ^ Hmh Thiit bi hd trd di chuyen xe lan O Viet Nam da cd cde cdng trinh nghiin cflu he thdng nang xe lan dpc eau thang bd den vdn chua thUe hien Tac gia Phara Dxtc Khdi eung cpng su [1] nghiin cflu tdp trung vao nang cao mflc dp linh boat eua xe ldn tu hdnh leo cau thang Tuy nhien, chi phi van hanh va mflc dp hilu qua vl nang lUdng, cung nhU mflc dp an toan d l ndng xe lan cd ngUdi van ehUa the hien tinh Uu viet Tren t h i gidi da ed nhilu nghien eflu ho trd cho ngUdi khuyet tdt nhU giup cho ngUdi khiem khuylt cd the tU phuc vu, giam di sU mac cam vdi xa hdi Tai lieu viet vl he cd cua cac thilt bi vd he thdng ndng va quy chuan an toan dupc td chflc Hoa Ky dUa tai lilu [2] Bin canh dd, cac nghiin cflu ve nhan trac hpe, cung cac trang thai nguy hilm flng dung thiet bi ndng ngUdi dUde trinh bay [3, 4] Kent, Jr [5] da phat minh ed he nang g h i va da nhan bang sang chl tai td chflc cdng nghe Hoa Ky nam Hinh PhUdng thdc di chuyin xe ldn ngUdi khuyit tdt 1992 Phat minh chi mdi flng dung cho thang len, xudng doc nang thang Dilu cd the xem la nen tang cua cae nghien cflu sau Cdc phat minh ve ghe tU Hinh trinh bay thilt hi van chuyen hanh theo cdu thang dUpc Szentistvany dUa ngudi len/xudng cau thang bd Cac thilt bi diu lay thUdng hieu ddc quyin la "STANNAH dupc flng dung rdt phd biln d cac nUdc phat triln STAIRLIFT" tai lieu 16] Cac nghien cflu ve tren t h i gidi tai nhflng ndi edng cdng nhU: Ga tau thiet bi nang dang cat keo dUa len cao da dUpc dien, trUdng hpc, viln bao tdng, v.v Cdn tai Vilt Houggyu [7] va Rashida [8] thUc hiln, trinh bay Nam thi hiln ehUa cd ndi nao flng dung he thong cae phuong phdp tdi Uu hda kit cau va md phdng Tfl nhflng phan tich trin ta thay dUdc sU can thiet bi dung phan m i m Pro/E Ngodi cdc nghien thilt cua vile nghiin cflu, thilt k l mot he thdng cflu trin, hien nay, cdc cdng ty cdn phat trien va hd trd ngUdi khuylt tat lln cdu thang phu hdp vdi thUdng m^i hda rat cdng ve thiet hi nang xe dilu kiln va mdi trUdng d Viet Nam lan dpc cau thang bd nhU: Cdng ty Bison, Acorn Stairlift, Axess, Ability, Platform Uft v.v ^ TAP CHi CO KHi VIET NAM, Sd nam 2013 Nhu da trinh bay d tren, ve thilt hi hd trp ngUdi khuyet tdt len/xudng ddc hoac cau thang da dUdc thilt ke flng dung rdng rai d Chau Au, Nhat ban, Han Qudc, v.v Hinh cac mau thilt bi cua cdc hang tren the gidi dUdc trinh bay an todn chdng va ch^m va phat h i l n vat can trin dudng ray (6) Cd cau ddng md san de xep xe gpn lai khdng sfl dung Sau qud trinh khao sdt cdc he thdng hd trd ngUdi khuyet tat hien cd tren the gidi Xe Pigata Nhat Ban san xuat dUdc chpn lam ddi tUdng de tham khao thiet ke md phdng (Hinh 5) Hinh He thong xe ndng cua cac cdng ty: (a) Axess; (b) Ability; (e) Platform Lift Tai Viet Nam, thilt bi hd trd cho ngUdi khuylt tat chi tap trung nghiin cflu, phat trien flng dung chfl yeu la xe lan De hd trd cho xe lan lln/xudng doc da cd nhieu de tai nghien cflu vl xe Ian, nhUng phai sfl dung he thdng dieu khien phflc tap vd chi phi trang bi cao Hien nay, xe lan tai Viet nam chu ylu dung sflc ngUdi Hinh (a) Thiet bi khungxe Pigata hodn chinh; (b) He khungxe Pigata Cac dang cdu thang cd the lap he thdng hd trd ngUdi khuyet tdt: Cdu thang dang thang (straight), edu thang dang cd khuc ngoat (curved stair): bao gdm cau thang ngoat dang cung tron, cdu thang ngodt 90" va cau thang ngoat ISO" Tat ca dupc the hien dUdi hinh Hinh (a) Dqngghingoi; (b) Dqng thiit bi chuyen chd xe ldn tay Dua vao kha nang van chuyen cua thilt bi nang, cdc he thdng ho trd ngUdi khuylt tat len cau thang cd the dUde phdn lam hai loai sau: dang ghe ngdi vd dang thilt bi chuyen chd xe lan tay (hinh 4) CAU TRUC CUA THIET BI H I thdng hd trd ngUdi khuyet tat len cau thang gdm cac bd phan chinh sau: (1) Tay vin lan can cau thang (2) Khung sUdn la ndi lap cac mach dien va co cau truyln ddng chinh (3) Tlianh bdo ve bao quanh ddi tUdng can van chuyen (4) Bang dilu khien dung de van hdnh xe (5) Thiet bi Hinh (a,b,c) Cdu thang dqng co nhdng khuc ngodt; (d) Cdu thang dqng thdng Thilt k l di kem vdi xe Pigata la mdt he thdng cau thang tUdng ddi phflc tg.p, duac lap co dinh len tUdng dpc theo hanh lang cau thang Xe cd the tu ddng x i p lai khdng dung tdi Khii lupng xe theo thilt ke la 152(kg) vd kha nang van chuyen ngUdi cung xe hd trd ngUdi khuylt tat KET QUA TfNH TOAN M O PHONG 3.1 Ddi tUdng tdi iiu nghiin ciiu TAP C H i C O KHi VIET NAM Sd nam 2013 Muc t i l u t r o n g bai bao la ddnh gii cac chdt Ifldng cua thilt kl: khdi lUpng (giam) vdi rang bupe ve flng suat va chuyen vi (trong gidi ban cho phep) Biln thilt k l Id nhflng tham sd he thdng dfldc thay ddi de tdi Uu kha nang lam viec cua thilt hi Trong tdi Uu hoa kich thUde chieu day cac tren kit cdu tang hay giam se quylt dinh sU thay doi flng suat vd chuyin vi cua he khung Trong nghiin cflu nay, flng sudt vd ehuyen vi dUdc sfl dung de gidi ban sU thay ddi chilu day cac tren khung xe Pigata thflc tai dupc trinh bay bang Tieu chuan chat lUdng phdn tfl dUde xem xet va dUde the hiln Bang 3.2 Tinh toan md phong he khung hiln tai Hmh Cdc chi tiit liin kit vdi bdng mdi hdn Md hinh khung dung thilt k l nhU hinh (b) Khung dan dUdc che t^o tfl eac loai thep cd biln dang khac nhU: thep hinh va thip tam, cdc thep dUdc lam tfl vdt lieu CT3 Cac bUdc thUc hien trpng qua trinh mo phdng cung cdc thdng sd ban ddu dUde trinh bay sau ddy: a) Chia lUdi vd cdc thdng s6 ban ddu Cde chi tilt tren khung dan dUde rdi rac bdi cac phan tfl dang shell vd phdn tfl Solid trin phan mem HyperWorks 11.0 Phdn tfl shell dung de rdi rac eho eac chi tilt dang mdng nhU chi tilt thep hop, V, U va tam Phan tfl Solid dung d l rdi r^c cho chi tilt dac nhU tren hinh Bdng Ihdng ki cdc thdng so cua mo hinh khung triide toi Uu Noi dung Khoi lUdng Dien tich The tich CTRIA3 CQUAD4 CPENTA RBE3 Thdng so 79,8 kg 2,931e+06mm'>2 l,01e+07 mm^a 332 (mo hinh phan tii) 178019 (m6 hinh phan ti) 1785 (lien ket moi han) 5674 (lien ket moi han) Bang2 Tiiu chudn chdt lUdngphdn tU cho mo hinh Max Warpape Max Aspect Ratio Max, Skew angle Min Jacobian Tria - Min Interior angle Tria - Max Interior angle Quad - Min Interior angle Quad - Max Interior angle 0,6.10' 2.27 37,5deg 0,61 30.13 deg 90,73 deg 45 deg 141,73 H\nh (a) Phdn td shell (Tria3 & Quad4) dung rdi b) Cdc rdng budc vd dieu kien bien rac chi tiet cd thdnh mong, (b) Phdn td solid (Hex8) diing rdi rac ddc Xe dupc gifl vflng vd chay dpc theo dUdng ray, qua trinh di chuyen xe se thudng xuyen Cae chi tilt trin khung xe dUde lien kit chiu tdc ddng eua tai tinh bao gdm lUdng bang mdi hdn, vi tri edc mdi ban theo dflng thUc ngUdi va xe lan trang thai tinh, kit ndi gifla xe te che tao nhu hinh Cac mdi hdn ndy chi rang va dudng ray la kit ndi cd dinh V\ tri kit ndi t h i cac cd cdc lien kit cflng vdi nhau, bdi hiln theo hinh bin dUdi Khi phan tlch bin, hai vi bao ndy chung tdi khdng nghiin cflu tinh toan tri dUde rang budc co dinh {ban chl bdc tU "^ ben cho mdi hdn Cac thdng sd md hinh khung do) nhu hinh TAP CHi CO KHi V I £ T NAM, S6 ndm 2013 3.2 Md phong tdi Uu hda kit cau he khung Tmh todn tdi Uu giam khdi lUdng khung xUdng dUdc thflc b i l n theo n h i l u each khdc nhau: thay ddi vat lieu thep t r i n k i t cau h i l n tai bang vdt lieu nhe hdn nhU vat lieu nhdra; tdi Uu bo tri lai k i t cdu khung xUdng; tdi Uu thay ddi chilu day tilt dien mat cat cac tren khung xfldng Phdn bd lai k i t cau khung xfldng dfldc thflc hien tren mien vat lieu lien tuc la khdi dat, sau thiJc Hmh Vi tri kit ndi xe vdi dUdng ray vd edc rdng budc hien bd bdt vung vat Ulu khdng can thilt dl co mdt kit cau tdi Uu Kit qua cua phUdng phap c6 dinh Id mdt thiet k l y tudng, vi vdy each ehi phu Cac tdi trpng va lflc tac dung len khung hdp vdi thilt k l ban ddu de tao hinh dang sd xe qua trinh van hanh dUdc xera xet: (1) Xe bd cfla k i t edu.Thay ddi tilt dien mat cat ngang sl chiu tac dung cua khdi lUdng tai bao gom khdi trin cdc tren khung xfldng dUde thUc hien lUdng ngUdi va khdi lUdng xe lan; (2) Lflc de dang ma khdng lam thay ddi thiet k l cu, each trudng P gay bdi khdi lUdng tai (m = 200kg) - thflc hiln phu hdp vdi nhflng thilt ke dang Vdi gia tdc trpng trUdng (g = 9,81m/s^) dUdc tinh dUde sdn xuat Sfl dung vat lieu nhe hdn nhU vat theo cdng thflc: P = m*g = 200*9,81 = 1962 (N), lieu nhdm d l thay the cho v^t lieu thep hien tai la lUe trpng trUdng se phdn bd tai vi tri bdnh xe cua xu hudng hien nay, n h i l n cdng nghl ban xe lan nhU hinh trin nhdm d cdc doanh nghiip bi han che va se tang ehi phi cho cdng nghl lien kit nen phfldng phap bi han che Trong nghien cflu ndy, tinh todn tdi Uu khung xe dUdc thUc hien dfla tren phUdng phap tdi Uu thay ddi chieu day cac tren khung Ham muc tilu la khoi lUdng khung xUdng toi thieu Rdng budc tdi Uu la flng suat trin tpan bp kit cau va chuyen vi ldn nhdt cho phep Biln thiet k l la chieu day cac thanh, biln thay ddi phu thupc vao dieu kiln vdt lilu thflc tl Hinh 10 (a) Kit qud chuyen vi theo phUdng Y; (b) Kit qud phdn tieh Ung sudt a) Hdm mtic tieu M(t) la ham khdi lUdng toan bo khung xUdng c) Ket qud trUdc toi Uu M(0^ Viec phdn tich chay md phdng phan tieh kilra tra ben dUdc thUc hiln tren mdy Workstation, 24Gb Ram, CPU 3.33GHz Thdi gian chay phdn tich 2,50 phut Kit qua nhdn dUdc: (1) Chuyin vi ldn nhat theo phUdng Y = 2,71 (mm); (2) iJng sudt ldn nhdt 94,5 (MPa) Ong suat tap trung tai vi tri cd cau gifl khung san, gid tri flng suat nam gidi han dan boi cua v^t lieu Kit qua dUdc chi tren hinh 10 I' Vdi j la sd lUdng loai thep tren khung; M la khdi lUdng tflng loai thep; M thay ddi ti 11 vdi chilu day t eua thanh, khdi lUdng thanh Mj nhd nhdt chilu day t cua nhd nhat Muc tieu tdi Uu la tim gia tri nhd nhat eua ham muc tieu, do: TAP CHi CO KHl VIET NAM Sd nam 2013 M(t) —*