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cng lun vn thc s GVHD : TS. HUNH THI HONG

HOCH NH NG I TI U CHO XE LNTHNG MINH

MC LC1/ t vn : ...........................................................................................................................3

1.1/ Gii thiu vn : ..........................................................................................................31.2/ ngha khoa hc: .........................................................................................................31.3/ ng dng thc tin: ......................................................................................................3

2/ Tng quan cc cng trnh lin quan v cc u khuyt im: ..............................................32.1/ Gii thut di truyn (Genetic Algorithm): ....................................................................52.2/ Gii thut di truyn kt hp vi iu khin m: .........................................................52.3/ Phng php Q-learning: ..............................................................................................62.4/ Xu hng nghin cu hin nay: ...................................................................................7

3/ Mc tiu ca ti: ..............................................................................................................73.1/ Kt qu d kin t c: ............................................................................................7

4/ Phng php nghin cu: ....................................................................................................84.1/ Gii thiu limit cycle: ...................................................................................................84.2/ Thut ton limit-cycles (vi vng o l ng trn): ..................................................84.3/ Thut ton limit cycle (vi ng o l ng ellipse): ............................................19

5/ Cu trc v ni dung d kin ca lun vn thc s: ..........................................................246/ K hoch thc hin lun vn: ............................................................................................24TI LIU THAM KHO ......................................................................................................25

HVTH: L THANH NGUYN 1

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LI CM N

Trc ht, em xin gi li cm n chn thnh nht n TS. HunhThi Hong, HBK HCM, ngi nhit tnh hng dn em trong qutrnh thc hin cng lun vn ny cng nh cung cp cho em nhngti liu gip nh hng nghin cu ca mnh... Bn cnh , em cng gili cm n cc bn trong i robot scoccer chia s nhng kinh nghimqu bu trong vic iu khin robot t hnh.

Em hi vng s c tip tc nhn c s h tr ca mi ngi trongthi gian ti c th hon tt chng trnh thc s ca mnh.

Xin chc mi ngi sc khe, an lnh, hnh phc

Thn iHc vin

L Thanh Nguyn


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1/ t vn :

1.1/ Gii thiu vn :

Ngy nay, khoa hc, k thut pht trin; cuc sng con ngi ny cng cnng cao; ci thin v cht v lng. Khi nhu cu cuc sng tng cao; con ngicng quan tm nhiu hn n s tin nghi; sc khe v.v.. cng chnh l l do mnhng chic xe ln y tay truyn thng c thay th dn bng nhng chic xe lnt hnh; nhng chic xe ln thng minh nhn bit v di chuyn theo mnh lnh cacon ngi.

Xe ln thng minh c nhiu nc tin tin trn th gii nghin cu vpht trin, tuy nhin vn cha hon thin ht v bi ton hoch nh ng i vn lvn mi; cn b ng nhiu vn cha gii quyt. i vi mt nc ang phttrin nh nc ta th vic tip cn; nghin cu mt chic xe ln nh vy l vn

mi m, l th v nhiu th thch. Trong , vic hoch nh ng i c nhgi l bi ton hay v mi, cn c quan tm.

Chnh v vy, trong khun kh ca lun vn; em xin xut cch tip cn vhng gii qut cho vic hoch nh ng i ti u cho xe ln thng minh.

1.2/ ngha khoa hc:

Vic hoch nh ng i cho xe ln thng minh s gp phn vo vic honthin hn gii thut iu khin chic xe ln; a ra mt gc nhn mi hn; mt cch

tip cn khc trong vic nghin cu, pht trin v c th t m rng ra nhnghng nghin cu khc tt hn, ti u hn cho vic iu khin xe ln thng minhni ring v iu khin robot ni chung, c bit l robot t hnh.

1.3/ ng dng thc tin:

ng dng vo vic iu khin; nghin cu pht trin, ch to xe ln thngminh thng minh nc ta; phc v cho cc bnh vin; ngi khuyt tt v ngigi.

2/ Tng quan cc cng trnh lin quan v cc u khuyt im:

Xe ln t hnh, bn t ng c nghin cu v pht trin nhiu nc vcc trng i hc trn th gii. Mt s cng trnh tiu biu c cng b nh :


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chic xe ln Aviator, ca gio s Nguyn Tn Hng, ngi c gc Vit, i hccng ngh Sydney:

Hay nh chic xe ln ca hng Toyota kt hp vi Vin khoa hc cng nghiptin tin quc gia Nht Bn (Japan's National Institute of Advanced IndustrialScience)

V cn nhiu hng khc na. Mc d tt c nhng sn phm trn u l nhngthnh tu khoa hc xut sc nht nhng vn hnh c chic xe ln vn phthuc nhiu vo ngi s dng; v vn hoch nh ng i vn cha c quan

tm v ng dng.

Khong hai thp k gn y; cc cng trnh lin quan n vn hoch nhng i cho robot, hay xe ln thng minh mi c cng b. Phn ln trong s s dng cc thut ton nh gii thut di truyn; iu khin m kt hp vi gii thutdi truyn; thut ton Q-learning Bn cnh , vic hoch nh ng i cn cgii quyt bng cc gii thut my tnh.


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C th tm lc mt s phng php tip cn trong vic hoch nh ng icho robot di ng, xe ln thng minh ca mt s cng trnh cng b:

2.1/ Gii thut di truyn (Genetic Algorithm):

Gii thut di truyn l mt k thut ca khoa hc my tnh nhm tm kim giiphp thch hp cho cc bi ton ti u t hp (combinatorial optimization). Giithut di truyn l mt phn ngnh ca gii thut tin ha vn dng cc nguyn lca tin ha nh di truyn, t bin, chn lc t nhin, v trao i cho.

Gii thut di truyn thng c ng dng nhm s dng ngn ng my tnh m phng qu trnh tin ho ca mt tp hp nhng i din tru tng (gi lnhng nhim sc th) ca cc gii php c th (gi l nhng c th) cho bi ton tiu ha vn . Tp hp ny s tin trin theo hng chn lc nhng gii php tthn.

Thng thng, nhng gii php c th hin di dng nh phn vi nhngchui 0 v 1, hoc cc chui s, nhng li mang nhiu thng tin m ha khc nhau.Qu trnh tin ha xy ra t mt tp hp nhng c th hon ton ngu nhin tt ccc th h. Trong tng th h, tnh thch nghi ca tp hp ny c c lng,nhiu c th c chn lc nh hng t tp hp hin thi (da vo th trng),c sa i (bng t bin hoc t hp li) hnh thnh mt tp hp mi. Tphp ny s tip tc c chn lc lp i lp li trong cc th h k tip ca giithut.

Do , vic ng dng gii thut di truyn gii bi ton hoch nh ng ihon ton c th tm ra c p n tt nht, ng i tt nht. Tuy nhin, n li

vp phi mt hn ch l ch ng dng tt trong mt mi trng c nh, bt bin. Vqun th ban u, hay chnh l nhng gi tr nh hng c ly thng tin t mitrng, hay mt a hnh, bn c th; do khi mi trng thay i; ton b ccgi tr tnh ton, thu thp thng tin phi lm li t u, gy lng ph thi gian v khp ng c i vi mi trng rng c nhiu s bin ng hay thay i t ngt.

2.2/ Gii thut di truyn kt hp vi iu khin m:

Mc tiu ca phng php ny l iu khin robot di ng n c vt cn vn c mc tiu. Trong , b iu khin m ng vai tr ra quyt nh; hngdn cho robot n vt cn v i n mc tiu; cn gii thut di truyn ti u ha bm. Phng php ny c th s dng trong nhng khng gian, nh cn phng nh,m c thng xuyn b di chuyn. Tuy nhin, vic thit k b iu khin mph thuc vo kinh nghim ca ngi thit k; bn cnh , cc kt qu cng bdng phng php ny p dng cho vic quy hoch ng i cha nhiu; ch mphng khng gian nh, n mt vt cn.

http://vi.wikipedia.org/wiki/Khoa_h%E1%BB%8Dc_m%C3%A1y_t%C3%ADnhhttp://vi.wikipedia.org/w/index.php?title=Gi%E1%BA%A3i_thu%E1%BA%ADt_ti%E1%BA%BFn_h%C3%B3a&action=edit&redlink=1http://vi.wikipedia.org/wiki/Ti%E1%BA%BFn_h%C3%B3ahttp://vi.wikipedia.org/wiki/Di_truy%E1%BB%81nhttp://vi.wikipedia.org/wiki/%C4%90%E1%BB%99t_bi%E1%BA%BFnhttp://vi.wikipedia.org/w/index.php?title=Ch%E1%BB%8Dn_l%E1%BB%8Dc_t%E1%BB%B1_nhi%C3%AAn&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=Trao_%C4%91%E1%BB%95i_ch%C3%A9o&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=M%C3%B4_ph%E1%BB%8Fng&action=edit&redlink=1http://vi.wikipedia.org/wiki/Nhi%E1%BB%85m_s%E1%BA%AFc_th%E1%BB%83http://vi.wikipedia.org/wiki/Nh%E1%BB%8B_ph%C3%A2nhttp://vi.wikipedia.org/wiki/Khoa_h%E1%BB%8Dc_m%C3%A1y_t%C3%ADnhhttp://vi.wikipedia.org/w/index.php?title=Gi%E1%BA%A3i_thu%E1%BA%ADt_ti%E1%BA%BFn_h%C3%B3a&action=edit&redlink=1http://vi.wikipedia.org/wiki/Ti%E1%BA%BFn_h%C3%B3ahttp://vi.wikipedia.org/wiki/Di_truy%E1%BB%81nhttp://vi.wikipedia.org/wiki/%C4%90%E1%BB%99t_bi%E1%BA%BFnhttp://vi.wikipedia.org/w/index.php?title=Ch%E1%BB%8Dn_l%E1%BB%8Dc_t%E1%BB%B1_nhi%C3%AAn&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=Trao_%C4%91%E1%BB%95i_ch%C3%A9o&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=M%C3%B4_ph%E1%BB%8Fng&action=edit&redlink=1http://vi.wikipedia.org/wiki/Nhi%E1%BB%85m_s%E1%BA%AFc_th%E1%BB%83http://vi.wikipedia.org/wiki/Nh%E1%BB%8B_ph%C3%A2n

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u ra : qu o ti u cho xe ln thng minh.

4/ Phng php nghin cu:C s l thuyt:

4.1/ Gii thiu limit cycle:

Phng php nh hng, hoch nh ng i dng limit cycle (limit cyclenavigation) l mt phng php nh hng mi c nh gi cao trong nhngnghin cu gn y . Vi nhng thng tin lin quan v v tr ca vt cn, mc tiu,robot v nhng vt cn lin quan n ng i ca robot, sau thay i hngchuyn ng dng cc vng o, i n mc tiu.

d tip cn, u tin s tm hiu thut ton limit cycle vi vng o l ng

trn, sau l ng ellipse.

4.2/ Thut ton limit-cycles (vi vng o l ng trn):

Nhim v ca vic nh hng cho i tng trong mi trng cha bit ldn robot n c mc tiu nh trc m vn trnh c cc vt cn c nh hocthay i. Gi s rng c vt cn v robot u c bao quanh bi cc hnh tr cbn knh ln lt l ,O RR R v mc tiu c xem nh mt vng trn nh c bnknh RT:

Hnh 1. Vng trn gii hn quanh vt cnTrong :

DROi : khong cch gia robot v vt cn iDPROi : di ng trc giao ca vt cn i vi ng lDTOi : khong cch gia vt cn v mc tiuROi : bn knh vt cnRIi : bn knh vng trn nh hng pht hin vt cn, ta a ra nh ngha vng trn nh hng, hay tm gi l

vng trn o vi bn knh c xc nh:


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Kt thc.Nh vy, ta thy r rng b iu khin da vo nhng tn hiu phn hi v m

a ra cc chn la. Nu khi tn hiu a v bo l robot ang gn vt cn th biu khin n vt cn s c kch hot; gip robot trnh n vt cn v sau tip tc chy ti mc tiu.

Hu ht cc b iu khin trnh vt cn ch c s dng khi robot tin tign vt cn (DROi < RIi). Khi s dng thut ton 1, b iu khin trnh vt cn sc kch hot ngay khi pht hin tn ti t nht mt vt cn nm trn ng dichuyn ca robot hng ti mc tiu (DPROi < RIi). V vy, trong khi c lng, don vic kch hot b iu khin trnh vt cn th thut ton 1 gim thi gian tinti mc tiu ca robot, c bit l trong mi trng ln xn.

Hnh 3. Hnh minh ha qu o robot khi c d bo, n vt cn

Thut ton phn cp la chn c dng qun l vic chn la gia hai haynhiu b iu khin khc nhau; v vy chin thut trnh vt cn c tch hp trongcu trc ca ton b iu khin.


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4.2.3/ Cc b iu khin c bn:

Cu trc ca b iu khin bao gm nhng b iu khin con khc nhau, ccb iu khin c bn. Nhng lut iu khin ny u c xy dng v da trniu kin n nh theo Lyapunov.

M hnh ng hc thun ca robot t hnh:

Hnh 4. Robot trong h ta tham chiu

2 1

2 1

cos cos sin

sin sin cos (1)

0 1

x l lv

y l lw

= = +

&

& &

&

Vi: x,y, l cc bin trng thi ca mt chu k ti im P t c ta vtung (l1, l2) tham chiu t h ta tng i (Xm, Ym).

v: vn tc di ca robot ti Ptw: vn tc gc ca robot ti Pt

4.2.4/ iu khin i n mc tiu:B iu khin ny dn ng cho robot tin v pha mc tiu, vi mc tiu

c minh ha l ng trn tm (xT, yT) bn knh RT (hnh 1). Lut iu khindng iu khin v tr ti im Pt = (l1, 0) (hnh 5). Ta xem mc tiu lmt vng trn c bn knh RT, v vy m bo ta tm robot hi t tim cnti mc tiu th l1 < RT.

Ta c:

1

1

cos sin(2)

sin cos

lx v vM

ly w w

= =

&

&

Vi M l ma trn kh nghch.

Sai s vi tr:x T

y T

e x x

e y y

= =

V tr ca mc tiu th khng thay i theo h quy chiu tuyt i, do :


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x

y

e x

e y

=

=

& &

& &

Nhng k thut c in n nh h thng tuyn tnh c th c dng nnh tim cn sai s v khng. y, ta s dng b iu khin t l:

1 , 0 (3)x

y

ev KM Kew

= >

Xt hm Lyapunov:

2 2 21

1, (4)

2 x yV d d e e= = +

d : khong cch gia robot v mc tiu. m bo cho vic n nh tim cn cho b iu khin th

1 0 0, 0V dd d < < >&& ; mt khc: , 0dd d

d ddt t

= 0, l hng s; v :

(10)e p eK = &Xt hm Lyapunov :

22

1(11)

2 eV =

Ta c : 22 0e e p eV K = =

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B e g i n

xO

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Hnh 6. hnh minh ha 4 vng c bit quanh vt cn.

4.2.5.3/ phn bit gia 4 vng trn:

nh ngha mt ta tham chiu mi (hnh 6) tha cc iu kin sau:Trc XO nm trn ng ni t tm vt cn ( , )obst obstx y ti tm ca mc tiu,

c chiu dng hng ti mc tiu.T XO quay mt gc 900 theo chiu dng lng gic ta c trc YO.S dng khung tham chiu ta khi thay i v tr ca robot, c ta

(x,y)A, (theo ta tuyt i), i vi khung tham chiu lin quan n vt cn(x,y)O. Vic chuyn i c thc hin khi s dng php bin i ng nht:

1cos sin 0

sin cos 0(12)0 0 0 1 0 0

1 0 0 0 1 1

obst

obst

O A

x x x

y y y

=

Mt khi cc thng tin cn thit c thu thp, ta c th a ra c qu o trnh vt cn, da vo thut ton 2. tnh ton c cc im, cn phi tnhc bn knh RC v hng ca chu k gii hn (limit cycle) i theo. V tr (x O,yO) a ra h (x,y) ca robot theo khung tham chiu ca vt cn. Vic nh ngha cth khung ta tham chiu s cung cp mt cng c robot bit chnh xc vc nphi lm. Thc t, du ca xO s gip robot phn bit hnh ng m n cn phi lm(i theo qu o ht hay y). Trong qu o pha y, chu k gii hn (limit cycle)

s ly nhiu gi tr bn knh khc nhau m bo s trn tru ca qu o. Du cayO s gip xc nh ng hng trnh vt cn.Thc t, nu y O 0, hng ca chuk gii hn (limit cycle) s thun theo chiu kim ng h, v ngc li s l ngcchiu kim ng h. S la chn ny cho php ti u di ca qu o ca robottrong vic trnh n vt cn. Tuy nhin, vic chn hng ny phi c thc hintrc khi b iu khin trnh vt cn c kch hot ti thi im (t-T).


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Tuy nhin, vi thut ton trnh vt cn nh trn, i khi cc b iu khinrobot s b xung t khi robot ri v cc v tr khng tt nh by cc b hay vngcht. khc phc cc li ny, ta a thm vo mt s lut iu khin b sung:

4.2.6/ Xc nh i tng tht s gy tr ngi trnh:

Trong nhng trng hp m cc vt cn giao nhau nh hnh 7:

Hnh 7. By cc b gia vt 1 v 2.

Nu ch p dng n thun thut ton 2; khi trnh vt th 1, robot s di chuyntheo hng ngc chiu kim ng h, nhng trnh vt 2, robot phi di chuyntheo chiu kim ng h, nh vy, robot b ri v by cc b gia 2 vt cn 1 v2. Do vy, ta s b sung thm lut iu khin chn vt trnh, kt qu thu c:

Hnh 8. Qu o robot sau khi b sung lut iu khinDi y l lu gii thut ca thut ton b sung cho b iu khin.


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Begin

DRO1 = DRO2

Chn min (DPROi)

DTO1 DTO2

Chn min (DTOi)

Chn bt k

End

D PRO1 D PRO2

Yes

Yes

No

No

Yes

Gin 3. Gii thut chn vt trnhV vy, vi tin thng tin lu tr ngn hn v cc hng ca vt cn, robot c

th thc hin d dng vic chuyn hng m vn trnh khng b ri vo nhngtrng hp khng mong mun nh by cc b hay vng cht v.v..

Bn cnh gii thut c a ra, thut ton 3, mt s cng trnh nghin cu vlimit cycle cng a ra bin php khc x l khi robot b ri vo by cc b nhtrng hp trn. Bin php m cc cng trnh s dng l to mt vt o ln hnbao trm ln cc vt o cn li. Ngha l nu c 2 vt cn b chng lp ln nhau nh


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trong hnh 7, th s to ra mt vng trn o vi bn knh ln bao trm c haivt cn, lc ny robot ch phi trnh vt cn ln .

Tuy nhin, bin php s l khng ti u nu vt cn c hnh dng di vhp nh bc tng chng hn. Lc ny, phi to ra mt vng trn rt ln c thbao trm c c bc tng, v r rng bn trong vn trn o khng phi ch

no cng l vt cn, v i khi trong nhng a hnh nh, vic to ra mt vng oqu ln s lm cho robot khng th i n mc tiu. Mt khc, ta nhn thy rngphng php ny t linh hot v cn ton b thng tin v tt c thng tin v ton bcc vt cn nm chng ln nhau, m i khi mt vi vt cn trong s khng lmnh hng lin ti vic di chuyn n mc tiu ca robot. Hnh di y minh hacho iu ny:

Hnh 9. Vt cn c dng ch UHiu qu ca thut ton 2, phn trnh vt cn, l loi b c s dao ng ca

qu o khi robot di chuyn men theo mp ca vt cn. Thut ton 2; phn tm RC,gin 2; cho php gip robot khng b dao ng gia v tr c DROi RIi (dng

kch hot b iu khin trnh vt cn) vi v tr c DROi RIi (dng kch hot biu khin hng ti mc tiu).

Hnh 10. Qu o robot, a) c dao ng, b) khng b dao ng


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4.3/ Thut ton limit cycle (vi ng o l ng ellipse):Thut ton limit cycle ellipse c pht trin trn nn limit cycle c vng o l

ng trn; phn ln cc cng thc tnh ton v gii thut c k tha, tuy nhincch t vn v cch tip cn c i cht khc bit.

Nhim v vn l nh hng cho robot di chuyn n mc tiu nh trctrong mt khng gian, mi trng khng bit trc. Vic ny phi c thc hinng thi vi vic trnh cc vt cn c nh hoc thay i vi cc kch thc vhnh dng khc nhau.

Ta gi s rng robot c bao bc bi hnh tr trn, c bn knh RR, cn vtcn c bao bc bi khi hp ellipse, v ng ellipse c cho bi cng thc:

2 2( ) ( ) ( )( ) 1 (13)a x h b y k c x h y k + + =

Hnh 11. Vng ellipse gii hn quanh vt cnVi:

h, k R, ta tm ellipse.a R+ , vi

1A

a= l mt na di ca trc di ca ellipse.

b R+ , vi1

Bb

= l mt na di ca trc ngn ca ellipse.

c R+ , vi gc nh hng ca ellipse 0.5*arctan( / ( ))c b a = DROi l khong cch nh nht ca robot vi vt cn i (hnh 11). pht hin tn tai vt cn, trong trng hp ny, iu khin l tn ti t

nht mt im giao nhau gia ng thng (l) v vng o ellipse (ellipse ofinfluence).

Thc t, vic nh ngha nhn thy vt cn, mt vn o ellipse phi c cc thuc tnh sau:

C cng tm (h,k) v gc nghing nh hnh ellipse bao quanh vt cn:Gi tr ca trc di ellipse l 2Alc vi : lc RA A R Ma= + + Gi tr ca trc ngn ellipse l 2Blc vi : lc RB B R Ma= + +


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Vi Ma c xem l dung sai an ton, bao gm : an ton iu khin, schnh xc v.v..

Vic s dng vng nh hng l ellipse s tng qut, linh ng hn trong vicbao xung quanh vt cn v ph hp vi nhiu hnh dng vt cn khc nhau. Mt vd in hnh nht l ng ellipse bao xung quanh mt bc tng s ph hp hn

mt ng trn

Hnh 12. Minh ha limit cycle bao quanh mt bc tng, a) ng trn, b)ellipse

4.3.1/ Cu trc iu khin ca limit cycle ellipse:

Cu trc ca b iu khin hon ton tng t vi phn limit cycle l ngtrn; tuy nhin cc b iu khin con c i cht khc bit.

4.3.2/ Thut ton : Phn cp chn la

Nhim v ging nh trn, phn phn cp chn la ca limit cycle ng trn;tuy nhin iu kin chn la th khc

(l) v ellipse c imchung

Trnh vtcn

Chy timc tiu

End

Begin

Yes

No

Gin 4. Thut ton phn cp chn la khi dng limit cycle ellipse


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4.3.3/ Cc b iu khin c bn:Ngoi tr b iu khin trnh vt cn, nhng phn cn li u ging phn

limit cycle vi vng o l ng trn.

4.3.4/ B iu khin trnh vt cn:

thc hin vic trnh cc chng ngi vt, robot cn theo chnh xc chu kgii hn ca trng vector (limit-cycle vector fields). Cc trng vector ny cchia lm 2 chiu khc nhau:

Qu o chuyn ng theo chiu kim ng h:2 2

2 2

2 2

2 2

(1 )

(14)

(1 )

s ss s s s s

lc lc

s ss s s s s

lc lc

x yx y x cx y

A B

x yy x y cx y

A B

= +

= +

&

&

Qu o chuyn ng ngc chiu kim ng h:2 22 2

2 2

2 2

(1 )

(15)

(1 )

s ss s s s s

lc lc

s ss s s s s

lc lc

x yx y x cx y

A B

x yy x y cx y

A B

= +

= +

&

&

Vi (xs, ys) l v tr tng i ca robot i vi tm ca ellipse. A lc, Blc mtna di cc trc di v ngn ca ellipse (hnh 11). Nu c khc 0; th l gc caellipse v l hng s dng.

Nu ellipse c trc di 2Alc = 4, trc ngn 2Blc = 2; th ellipse l mt chu k

qu o, hay cn gi l mt chu k gii hn (limit cycle):

Hnh 13. Hnh dng kh dng limit cycle ellipsea) chiu kim ng h, b) ngc chiu kim ng h


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Cc qu o xut pht t im (xs, ys) theo khung tham chiu X, Y; bao gmbn trong ellipse, di chuyn v pha ellipse. iu ny c th c chng minh tonhc khi s dng hm Lyapunov :

2 21( ) ( ) (16)2 s s

V x x y= +

o hm V(x) theo qu o ca h thng ta c: ( ) s s s sV x x x y y= +& & &Sau mt vi php bin i, thay th, ta c:

2 2

2 2( ) ( )(1 ) (17)s s

s s

lc lc

x yV x V x cx y

A B= &

o hm ( )V x& s m nu2 2

2 2(1 ) 0s s

s s

lc lc

x ycx y

A B < , tng ng vi iu kin

u (xs0, ys0) bn ngoi hng vo trong ellipse, cng thc (13), v ( )V x& s dngnu iu kin u (xs0, ys0) bn trong hng ra bn ngoi. V hng s cng lnth vn tc hi t ca chu k gii hn v chu k qu o cng nhanh.

iu khin robot i theo cc qu o hnh ellipse ny, ta s dng lut iukhin nh hng, hay mt da vo mt i lng gi l gc nh hng d . Cngthc tnh i lng ny, cng nh lut iu khin nh hng c trnh by trongcc cng thc t (7) ti (11) phn trn.

4.3.4.1/ Thut ton 5: gii thut n vt cn vi limit cycle ellipse:

Hnh 14. 4 vng xung quanh vt cnLu gii thut:

u vo cho thut ton : tt c thng tin lin quan n vt cn gn nht, gi tr

u ra ca thut ton : cc c tnh qu o ca limit cycle robot bm theo.


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Begin

xO

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5/ Cu trc v ni dung d kin ca lun vn thc s:

1. Chng 1: Gii thiui. t vn .

ii. Nghin cu tng quan.iii. Tm lc ni dung nghin cu.iv. Tnh cp thit ca ti.

2. Chng 2 : Tng quani. Nhng cng trnh nghin cu trn th gii c lin quan.

ii. u im v khuyt im ca cc cng trnh ny.iii. Nhng hng pht trin khc c th khai thc.

3. Chng 3 : C s l thuyti. Gii thiu limit cycle.

ii. L thuyt cho b iu khin n mc tiu.iii. L thuyt cho b iu khin trnh vt cn.iv. L thuyt cho b chn la ti u.

4. Chng 4 : Xy dng gii thuti. Gii thut cho b iu khin tng qut.

ii. Gii thut ca b iu khin n mc tiu.iii. Gii thut cho b iu khin trnh vt cn.iv. Gii thut la chn, hoch nh cho qu o ti u.

5. Chng 5 : ng dngi. Chng trnh tnh ton Matlab.

ii. M phng Matlab.iii. Kt qu m phng.

iv. Kt qu thc nghim.6. Chng 6 : Kt lun

i. Kt qu.ii. Hng pht trin.

7. Ti liu tham kho.

6/ K hoch thc hin lun vn:

Thi gian d kin thc hin ti : 1 hc k (khong 4 thng)STT Tn cng vic Thi gian Kt qu cn t Ghi ch

1 c ti liu 1 thng Nm tng quan v lthuyt

2 Xy dng gii thut, vitchng trnh

1 thng Hon thnh s bchng trnh

Bo co50%

3 Ci tin chng trnh 1 thng Hon thnh chngtrnh m phng

4 Xy dng m hnh v vitbo co lun vn

1 thng Kim chng kt quthc nghim

Bo cott nghip


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TI LIU THAM KHO

[1] A Mobile Robot Path Planning Using Genertic Algorithm in Static Enviroment, Ismail AL-Taharwa, Alaa Sheta and Mohammed Al-Weshah, Al-Baqa AppliedUniversity, Al-Salt, Jordan.[2] Optimal Trajectory of a Mobile Robot by a Genetic Design Fuzzy LogicController, Chokri REKIK, Mohammed JALLOULI and Nabil DERBEL,University of Sfax.[3] Optimal Path Planning for Mobile Robot Navigation, Gene Eu Jan, Ki YinChang, and Ian Paberry, IEEE/ASME Transactions on mechatronics, vol 13, No 4,August 2008.

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