Thaum sib piv durability, flatHingeIt ua pov thawj zoo tshaj rau niam-me nyuam pob khawm. Txawm hais tias qhov ntev ntawm niam-me nyuam pob khawm yog tib yam li ntawm th

Cov lus piav qhia: Qhov kev sib hloov ntawm qhov tsis sib xws ntawm xoom-qhib pob khawm hloov pauv yog kwv yees li xoom, uas kov yeej qhov tsis xws luag uas cov pob khawm hloov tau yooj yim yuav tsum tau tsav lub zog, thiab tuaj yeem siv rau kev hloov pauv thiab lwm yam haujlwm. Siv lub nplhaib sab hauv thiab sab nrauv hloov tau yooj yim nyob rau hauv qhov kev txiav txim ntawm cov ntshiab torque raws li qhov zoo txhav subsystem, kev tshawb fawb tsis pom kev nruj mechanism thiab txuam qhov zoo thiab qhov tsis zoo tawv tuaj yeem tsim xoom txhav saj zawg zog pob khawm. Npaj ib tug tsis zoo txhav rotation mechanism——Crank caij nplooj ntoos hlav mechanism, qauv thiab soj ntsuam nws cov yam ntxwv tsis zoo nruj; los ntawm kev sib piv qhov zoo thiab qhov tsis zoo nruj, txheeb xyuas qhov cuam tshuam ntawm cov qauv tsis sib xws ntawm crank caij nplooj ntoos hlav mechanism ntawm xoom txhav zoo; npaj lub caij nplooj ntoos hlav linear nrog customizable txhav thiab loj——Pob zeb diamond-zoo li tus nplooj caij nplooj ntoos hlav hlua, tus qauv nruj tau tsim thiab lub caij nyoog simulation pov thawj tau ua tiav; Thaum kawg, kev tsim, ua thiab kev sim ntawm ib qho kev sib cog lus xoom-qhib hloov pauv pob khawm tau ua tiav. Cov txiaj ntsig tau sim pom tias: nyob rau hauv qhov kev txiav txim ntawm lub zog ntshiab,±18°Nyob rau hauv qhov ntau ntawm kev sib hloov lub kaum sab xis, qhov kev sib hloov nruj ntawm xoom-qhib hloov pob khawm yog 93% qis dua li ntawm lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim ntawm qhov nruab nrab. Lub tuam tsev xoom-nruj saj zawg zog pob khawm muaj cov qauv compact thiab high-zoo xoom-stiffness; lub tswv yim tsis zoo-nruj kev sib hloov mechanism thiab linear Lub caij nplooj ntoos hlav muaj txiaj ntsig zoo rau kev kawm txog kev hloov pauv hloov pauv.

0 lus qhia

Flexible pob khawm (cov kabmob)

[1-2]

Relying ntawm elastic deformation ntawm lub saj zawg zog chav tsev xa los yog hloov cov lus tsa suab, quab yuam thiab lub zog, nws tau dav siv nyob rau hauv precision positioning thiab lwm yam teb. Piv nrog rau cov kabmob nruj nruj, muaj lub sijhawm rov qab los thaum lub pob khawm hloov pauv. Yog li ntawd, lub tsev tsav yuav tsum muab cov zis torque los tsav thiab Khaws qhov kev sib hloov ntawm lub pob khawm hloov tau. Zero stiffness saj zawg zog pob khawm

[3]

(Zero stiffness flexural pivot, ZSFP) yog ib qho kev hloov pauv hloov pauv uas nws qhov kev sib hloov yog kwv yees li xoom. Hom pob khawm hloov tau yooj yim no tuaj yeem nyob ntawm txhua txoj haujlwm nyob rau hauv cov kab mob stroke, tseem hu ua static balance flexible pob khawm

[4]

, feem ntau yog siv nyob rau hauv teb xws li saj zawg zog grippers.

Raws li lub tswv yim tsim qauv ntawm lub tswv yim hloov tau yooj yim, tag nrho xoom-ntiv nplhaib hloov tau yooj yim pob khawm tuaj yeem muab faib ua ob lub kaw lus ntawm qhov zoo thiab qhov tsis zoo, thiab qhov xoom-qhib qhov system tuaj yeem pom tau los ntawm kev sib txuam ntawm qhov zoo thiab qhov tsis zoo.

[5]

. Ntawm lawv, qhov zoo txhav subsystem feem ntau yog qhov loj-stroke saj zawg zog pob khawm, xws li tus ntoo khaub lig-reed saj zawg zog pob khawm.

[6-7]

, generalized peb-cross reed saj zawg zog pob khawm

[8-9]

thiab sab hauv thiab sab nplhaib hloov tau hinges

[10-11]

lwm. Tam sim no, kev tshawb fawb ntawm cov pob khawm hloov pauv tau ua tiav ntau qhov txiaj ntsig, yog li ntawd, tus yuam sij rau kev tsim xoom-qhib flexible hinges yog kom phim cov qauv tsis zoo rau cov pob khawm yooj yim[3].

Lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim pob khawm (Inner thiab txheej nplhaib flexural pivots, IORFP) muaj cov yam ntxwv zoo heev ntawm kev nruj, precision thiab kub drift. Qhov kev sib txuam tsis zoo nruj module muab cov qauv kev tsim kho ntawm xoom-nruab pob khawm hloov tau yooj yim, thiab thaum kawg, ua tiav cov qauv tsim, qauv ua thiab kev sim ntawm xoom-qhib hloov pob khawm.

1 crank caij nplooj ntoos hlav mechanism

1.1 Lub ntsiab lus ntawm qhov tsis zoo tawv nqaij

Cov ntsiab lus dav dav ntawm qhov tawv nqaij K yog tus nqi ntawm kev hloov pauv ntawm qhov load F yug los ntawm cov khoom elastic thiab qhov sib thooj deformation dx

K = dF/dx (1)

Thaum lub load increment ntawm lub elastic caij yog opposite rau lub cim ntawm tus coj deformation increment, nws yog tsis zoo rigidity. Lub cev, qhov tsis zoo tawv nqaij sib raug rau qhov tsis zoo li qub ntawm cov khoom elastic

[12]

.Negative txhav mechanisms ua lub luag hauj lwm tseem ceeb nyob rau hauv lub teb ntawm saj zawg zog tshuav nyiaj li cas. Feem ntau, tsis zoo txhav mechanisms muaj cov yam ntxwv hauv qab no.

(1) Lub tshuab khaws cia qee lub zog lossis ua rau muaj qee yam deformation.

(2) Lub tshuab yog nyob rau hauv ib qho tseem ceeb instability xeev.

(3) Thaum lub tshuab muaj kev cuam tshuam me ntsis thiab tawm ntawm txoj haujlwm sib npaug, nws tuaj yeem tso tawm lub zog loj dua, uas yog nyob rau tib qho kev txav mus los.

1.2 Kev tsim kho lub hauv paus ntsiab lus ntawm xoom-stiffness saj zawg zog pob khawm

Lub xoom-stiffness saj zawg zog pob khawm tuaj yeem tsim los ntawm kev siv qhov zoo thiab qhov tsis zoo ntawm qhov sib txuam, thiab cov ntsiab lus tau qhia hauv daim duab 2.

(1) Nyob rau hauv qhov kev txiav txim ntawm ntshiab torque, lub puab thiab sab nplhaib hloov tau yooj yim hinges muaj ib tug kwv yees li linear torque-tso lub kaum sab xis kev sib raug zoo, raws li qhia nyob rau hauv daim duab 2a. Tshwj xeeb tshaj yog, thaum qhov kev sib tshuam taw tes nyob rau ntawm 12.73% ntawm lub reed ntev, lub torque-rotation lub kaum sab xis kev sib raug zoo yog linear

[11]

, nyob rau lub sijhawm no, lub sijhawm rov qab Mpivot (clockwise kev taw qhia) ntawm lub pob khawm hloov tau muaj feem xyuam nrog lub kaum sab xis ntawm cov kabmob.θ(counterclockwise) kev sib raug zoo

Mpivot = (8EI/L)θ (2)

Nyob rau hauv cov mis, E yog lub elastic modulus ntawm cov khoom, L yog qhov ntev ntawm reed, thiab kuv yog lub sij hawm ntawm inertia ntawm seem.

(2) Raws li cov qauv kev sib hloov ntawm lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim, qhov tsis zoo ntawm qhov kev sib hloov yog sib npaug, thiab nws cov yam ntxwv tsis zoo yog qhia hauv daim duab 2b.

(3) Nyob rau hauv kev saib ntawm instability ntawm qhov tsis zoo txhav mechanism

[12]

, qhov txhav ntawm qhov xoom-qhib hloov pob khawm yuav tsum yog kwv yees li xoom thiab ntau dua xoom, raws li qhia hauv daim duab 2c.

1.3 Lub ntsiab lus ntawm crank caij nplooj ntoos hlav mechanism

Raws li cov ntaub ntawv [4], ib qho xoom-qhib pob khawm hloov tau tuaj yeem tsim los ntawm kev qhia lub caij nplooj ntoos hlav ua ntej deformed ntawm lub cev txav mus thiab lub cev khov kho ntawm lub pob khawm hloov tau. Rau lub nplhaib puab thiab sab nraud hloov tau pob khawm qhia hauv FIG. 1, lub caij nplooj ntoos hlav yog qhia nruab nrab ntawm lub nplhaib puab thiab lub nplhaib sab nraud, I.e., lub caij nplooj ntoos hlav-crank mechanisms (SCM) tau qhia. Xa mus rau lub crank slider mechanism qhia nyob rau hauv daim duab 3, cov tsis muaj feem xyuam rau lub crank caij nplooj ntoos hlav mechanism yog qhia nyob rau hauv daim duab 4. Lub tshuab crank-caij nplooj ntoos hlav yog tsim los ntawm lub crank thiab lub caij nplooj ntoos hlav (teeb rigidness li k). lub kaum sab xis pib yog lub kaum sab xis ntawm lub crank AB thiab lub hauv paus AC thaum lub caij nplooj ntoos hlav tsis deformed. R sawv cev rau qhov ntev crank, l sawv cev rau qhov ntev ntawm lub hauv paus, thiab txhais cov crank length ratio raws li qhov piv ntawm r rau l, I.e. = r/l (0<<1).

Kev tsim kho ntawm crank-caij nplooj ntoos hlav mechanism yuav tsum tau txiav txim siab ntawm 4 tsis: lub hauv paus ntev l, crank length ratio, thawj lub kaum sab xis thiab lub caij nplooj ntoos hlav stiffness K.

Lub deformation ntawm lub crank caij nplooj ntoos hlav mechanism nyob rau hauv quab yuam yog qhia nyob rau hauv daim duab 5a, lub caij M

γ

Nyob rau hauv qhov kev txiav txim, lub crank tsiv los ntawm thawj txoj hauj lwm AB

Beta

tig to AB

γ

, thaum lub sij hawm kev sib hloov, lub kaum sab xis ntawm lub crank txheeb ze rau txoj hauj lwm kab rov tav

γ

hu ua crank angle.

Kev soj ntsuam zoo qhia tau hais tias lub crank tig los ntawm AB (pib txoj hauj lwm, M & gamma; 0) to AB0“point tuag”qhov chaw, M

γ

yog xoom), lub crank-lub caij nplooj ntoos hlav mechanism muaj ib tug deformation nrog tsis zoo nruj yam ntxwv.

1.4 Kev sib raug zoo ntawm torque thiab rotation kaum ntawm crank caij nplooj ntoos hlav mechanism

Hauv daim duab. 5, zog m & gamma; clockwise yog qhov zoo, lub crank lub kaum sab xis & gamma; counterclockwise yog qhov zoo, thiab lub sijhawm thauj khoom M yog qauv thiab ntsuas hauv qab no.

γ

nrog crank angle

γ

Kev sib raug zoo ntawm cov txheej txheem ua qauv yog dimensioned.

Raws li pom hauv daim duab 5b, qhov sib npaug ntawm qhov sib npaug rau crank AB & gamma yog teev.

Hauv cov qauv, F & gamma; yog lub caij nplooj ntoos hlav restoring quab yuam, d & gamma; yog F & gamma; rau point A. Nco ntsoov tias qhov kev hloov pauv-load kev sib raug zoo ntawm lub caij nplooj ntoos hlav yog

Nyob rau hauv cov mis, K yog lub caij nplooj ntoos hlav txhav (tsis tas tus nqi tas li),δ
xγ

yog tus nqi ntawm lub caij nplooj ntoos hlav deformation (shortened rau zoo),δ
xγ

=|B

Beta

C| – |B

γ

C|.

Simultaneous type (3)(5), moment M

γ

nrog ces kaum

γ

Kev sib raug zoo yog

1.5 Kev tshuaj xyuas qhov tsis zoo ntawm cov yam ntxwv ntawm lub tshuab crank-caij nplooj ntoos hlav

Txhawm rau ua kom yooj yim rau kev txheeb xyuas qhov tsis zoo ntawm cov yam ntxwv ntawm lub crank-caij nplooj ntoos hlav mechanism (lub sijhawm M

γ

nrog ces kaum

γ

kev sib raug zoo), tej zaum nws yuav xav tias lub caij nplooj ntoos hlav muaj ib tug linear zoo rigidity, ces formula (4) rewritten li

Nyob rau hauv tus qauv, Kconst yog qhov tas li ntau dua xoom. Tom qab qhov loj ntawm lub pob khawm hloov tau txiav txim siab, qhov ntev l ntawm lub hauv paus kuj tau txiav txim siab. Yog li ntawd, piv txwv tias l yog qhov tsis tu ncua, formula (6) tuaj yeem sau dua li

qhov twg Kconstl2 yog qhov tsis tu ncua ntau dua xoom, thiab lub sijhawm coefficient m & gamma; muaj ib tug dimension. Cov yam ntxwv tsis zoo ntawm lub crank-caij nplooj ntoos hlav mechanism tuaj yeem tau txais los ntawm kev txheeb xyuas kev sib raug zoo ntawm torque coefficient m & gamma; thiab lub kaum sab xis tig & gamma.

Los ntawm kab zauv (9), Daim duab 6 qhia lub kaum sab xis pib =π kev sib raug zoo ntawm m & gamma; thiab crank length ratio thiab tig lub kaum sab xis & gamma; & ib; [0.1, 0.9],& gamma;& ib; [0, π]. Daim duab 7 qhia txog kev sib raug zoo ntawm m & gamma; thiab tig lub kaum sab xis & gamma; rau = 0.2 thiab txawv. Daim duab 8 qhia =π Thaum, nyob rau hauv sib txawv, kev sib raug zoo ntawm m & gamma; thiab lub kaum sab xis & gamma.

Raws li lub ntsiab lus ntawm crank caij nplooj ntoos hlav mechanism (section 1.3) thiab mis (9), thaum k thiab l yog tas mus li, m & gamma; Tsuas yog hais txog lub kaum sab xis & gamma;, crank length ratio thiab crank thawj lub kaum sab xis.

(1) Yog thiab tsuas yog yog tias & gamma; yog 0 orπ sau, m & gamma; yog sib npaug rau xoom; & gamma; & ib; [0,],m & gamma; yog ntau tshaj xoom; & gamma; & ib ;[π], m & gamma; tsawg dua xoom. & ib; [0,],m & gamma; yog ntau tshaj xoom; & gamma;& ib ;[π], m & gamma; tsawg dua xoom.

(2) & gamma; Thaum [0,], lub kaum sab xis tig & gamma; nce, m & gamma; nce ntawm xoom mus rau lub inflection point kaum & gamma; 0 siv tus nqi siab tshaj m & gamma; max, thiab ces maj mam txo.

(3) Cov yam ntxwv tsis zoo ntawm lub crank caij nplooj ntoos hlav mechanism: & gamma;& ib; [0, & gamma;0], lub sijhawm no & gamma; nce (counterclockwise), thiab torque M & gamma; nce (clockwise). Lub inflection point angle & gamma; 0 yog lub siab tshaj plaws kev sib hloov lub kaum sab xis ntawm qhov tsis zoo nruj tus yam ntxwv ntawm crank-caij nplooj ntoos hlav mechanism thiab & gamma;0 & ib; [0,];m & gamma; max yog qhov siab tshaj plaws lub sij hawm tsis zoo coefficient. Muab thiab , qhov sib npaug ntawm qhov sib npaug (9) yields & gamma;0

(4) qhov loj dua qhov pib lub kaum sab xis, & gamma; loj 0,m

γ max

loj dua.

(5) qhov loj qhov ntev piv, & gamma; qis 0,m

γ max

loj dua.

Hauv particular, =πCov yam ntxwv tsis zoo ntawm lub crank caij nplooj ntoos hlav mechanism yog qhov zoo tshaj plaws (qhov tsis zoo ntawm lub kaum sab xis yog qhov loj, thiab lub zog uas tuaj yeem muab tau yog loj). =πNyob rau tib lub sijhawm, nyob rau hauv cov xwm txheej sib txawv, qhov siab tshaj plaws tig lub kaum sab xis & gamma ntawm qhov tsis zoo tawv tus yam ntxwv ntawm crank caij nplooj ntoos hlav mechanism; 0 thiab qhov siab tshaj plaws torque coefficient m & gamma; Max yog teev nyob rau hauv cov lus 1.

Table 1 Lub kaum sab xis pib yogπ Qhov siab tshaj plaws tsis zoo lub kaum sab xis & gamma; 0 thiab lub sijhawm siab tshaj plaws coefficient m nyob rau hauv qhov sib txawv crank length ratios

γ max

parameter

Ntaus

crank ntev ratio

0.1

0.2

0.3

0.4

0.5

Max tig lub kaum sab xis & gamma;

0
/rad

0.98

0.91

0.84

0.76

0.68

Maximum caij coefficient m

γ max

0.013

0.055

0.13

0.23

0.37

2 Kev tsim kho ntawm xoom-stiffness saj zawg zog pob khawm

Qhov sib txuam ntawm qhov zoo thiab qhov tsis zoo ntawm qhov 2.1 yog pom nyob rau hauv daim duab 9, n (n 2) pawg ntawm parallel crank caij nplooj ntoos hlav mechanisms yog tusyees faib nyob ib ncig ntawm lub circumference, tsim ib tug tsis zoo txhav mechanism matched nrog lub puab thiab sab nraud nplhaib hloov tau yooj yim hinges.

Siv lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim pob khawm raws li qhov zoo tawv tawv subsystem, tsim kom muaj xoom-qhib pob khawm yooj yim. Yuav kom ua tiav xoom txhav, phim qhov zoo thiab qhov tsis zoo nruj

ib txhij (2), (3), (6), (11), thiab & gamma; =θ, lub load F & gamma ntawm lub caij nplooj ntoos hlav tuaj yeem tau txais; thiab tshem tawmδKev sib raug zoo ntawm x & gamma; yog

Raws li tshooj 1.5, qhov tsis zoo ntawm lub kaum sab xis ntawm lub tshuab crank caij nplooj ntoos hlav: & gamma;& ib; [0, & gamma;0] ua & gamma;0 & isin; [0, ], lub stroke ntawm xoom txhav hloov pob khawm yuav tsum tsawg dua & gam;0, ib. lub caij nplooj ntoos hlav yog ib txwm nyob rau hauv lub xeev deformed (δxγ≠ 0). Kev sib hloov ntau yam ntawm lub nplhaib puab thiab sab nraud hloov tau yooj yim hinges yog±0.35 hli (±20°), simplify lub trigonometric functions kev txhaum & gamma; thiab cos & gamma; raws li nram no

Tom qab simplification, load-tsav kev sib raug zoo ntawm lub caij nplooj ntoos hlav

2.2 Kev soj ntsuam yuam kev ntawm qhov zoo thiab qhov tsis zoo ntawm qhov sib piv cov qauv

Ntsuas qhov yuam kev los ntawm kev kho kom yooj yim ntawm kev sib npaug (13). Raws li qhov tseeb ua tsis tau ntawm xoom txhav saj zawg zog pob khawm (Section 4.2): n = 3,l = 40mm, =π, = 0.2, E = 73 GPa; Qhov ntev ntawm lub nplhaib puab thiab sab nraud hloov tau pob khawm Reed L = 46mm, T = 0.3mm, W = 9.4mm; Cov qauv kev sib piv (12) thiab (14) ua kom yooj yim rau kev sib txuas ntawm kev thauj khoom thiab cov txheeb ze yuam kev ntawm lub hauv ntej thiab nram qab springs raws li qhia nyob rau hauv daim duab 10a thiab 10b feem.

Raws li pom hauv daim duab 10, & gamma; tsawg dua 0.35 rad (20°), tus txheeb ze yuam kev tshwm sim los ntawm kev kho kom yooj yim rau lub load-tsav nkhaus tsis tshaj 2.0%, thiab cov qauv

Kev kho kom yooj yim ntawm (13) tuaj yeem siv los tsim xoom-nruj khawm hloov tau yooj yim.

2.3 Cov yam ntxwv nruj ntawm lub caij nplooj ntoos hlav

Piv txwv tias qhov nyuaj ntawm lub caij nplooj ntoos hlav yog K, ib txhij (3), (6), (14)

Raws li qhov tseeb ua tsis tau ntawm xoom txhav saj zawg zog pob khawm (Section 4.2), qhov hloov nkhaus ntawm lub caij nplooj ntoos hlav txhav K nrog lub kaum sab xis & gamma; yog qhia hauv daim duab 11. Tshwj xeeb, thaum & gamma;= 0, K siv tus nqi tsawg kawg nkaus.

Rau qhov yooj yim ntawm kev tsim thiab kev ua haujlwm, lub caij nplooj ntoos hlav siv lub caij nplooj ntoos hlav zoo zoo, thiab qhov tawv tawv yog Kconst. Nyob rau hauv tag nrho cov mob stroke, yog tias tag nrho cov tawv nqaij ntawm lub xoom stiffness saj zawg zog pob khawm yog ntau dua los yog sib npaug rau xoom, Kconst yuav tsum coj tus nqi tsawg kawg nkaus ntawm K

Qhov sib npaug (16) yog tus nqi txhav ntawm lub caij nplooj ntoos hlav zoo khov kho thaum tsim cov xoom txhav hloov pob khawm. 2.4 Kev soj ntsuam ntawm xoom-stiffness zoo Qhov kev sib raug zoo ntawm kev sib txuas ntawm cov khoom siv xoom-qhib lub pob khawm yog

Simultaneous formula (2), (8), (16) tau

Txhawm rau ntsuas qhov zoo ntawm xoom txhav, qhov txo qis ntawm cov pob khawm hloov tau yooj yim ua ntej thiab tom qab ntxiv qhov tsis zoo qhov tawv nqaij yog txhais tau tias yog xoom txhav zoo coefficientηη Qhov ze rau 100%, qhov siab dua qhov zoo ntawm xoom txhav. Daim duab 12 yog 1-η Kev sib raug zoo nrog crank length ratio thiab pib lub kaum sab xis η Nws yog ywj siab ntawm tus naj npawb n ntawm kev sib txuas crank-caij nplooj ntoos hlav mechanisms thiab qhov ntev l ntawm lub hauv paus, tab sis tsuas yog cuam tshuam nrog lub crank ntev piv, lub kaum sab xis. & gamma; thiab pib lub kaum sab xis.

(1) Lub kaum sab xis pib nce thiab xoom txhav zoo txhim kho.

(2) Qhov sib piv ntev nce thiab xoom txhav zoo txo ​​qis.

(3) Lub kaum sab xis & gamma; nce, xoom stiffness zoo txo.

Txhawm rau txhim kho qhov xoom txhav zoo ntawm xoom txhav hloov pob khawm, thawj lub kaum sab xis yuav tsum coj tus nqi loj dua; lub crank length ratio yuav tsum tsawg li tsawg tau. Nyob rau tib lub sijhawm, raws li kev txheeb xyuas cov txiaj ntsig hauv Tshooj 1.5, yog tias me me dhau lawm, lub peev xwm ntawm crank-caij nplooj ntoos hlav mechanism muab qhov tsis zoo nruj yuav tsis muaj zog. Txhawm rau txhim kho qhov xoom txhav zoo ntawm xoom txhav yooj yim pob khawm, thawj lub kaum sab xis =π, crank ntev piv = 0.2, uas yog, qhov ua tsis tau tiag tiag ntawm ntu 4.2 xoom txhav hloov pob khawm.

Raws li qhov tseeb ua tsis tau ntawm xoom-stiffness saj zawg zog pob khawm (Section 4.2), torque-angle kev sib raug zoo ntawm lub puab thiab sab nplhaib hloov tau yooj yim hinges thiab xoom-stiffness saj zawg zog pob khawm yog qhia nyob rau hauv daim duab 13; Qhov txo qis hauv qhov tawv nqaij yog xoom-stiffness zoo coefficientηKev sib raug zoo nrog lub ces kaum & gamma; yog qhia hauv daim duab 14. Los ntawm daim duab 14: Hauv 0.35 rad (20°) kev sib hloov ntau yam, qhov nruj ntawm xoom-qhib lub pob khawm hloov tau raug txo los ntawm qhov nruab nrab ntawm 97%; 0.26 hli (15°) ces kaum, nws yog txo los ntawm 95%.

3 Tsim ntawm linear zoo rigidity caij nplooj ntoos hlav

Kev tsim kho ntawm xoom stiffness saj zawg zog pob khawm feem ntau yog tom qab qhov loj thiab nruj ntawm lub pob khawm hloov tau raug txiav txim siab, thiab tom qab ntawd qhov nruj ntawm lub caij nplooj ntoos hlav hauv lub caij nplooj ntoos hlav crank yog thim rov qab, yog li qhov nruj thiab qhov xav tau ntawm lub caij nplooj ntoos hlav yog nruj heev. Tsis tas li ntawd, thawj lub kaum sab xis =π, los ntawm daim duab 5a, thaum lub sij hawm kev sib hloov ntawm lub xoom-qhib zawv zawg pob khawm, lub caij nplooj ntoos hlav yog ib txwm nyob rau hauv lub xeev compressed, uas yog“Compression caij nplooj ntoos hlav”.

Qhov nruj thiab qhov loj ntawm cov tsoos compression springs yog qhov nyuaj rau kev kho kom raug, thiab cov txheej txheem qhia feem ntau yuav tsum tau siv hauv cov ntawv thov. Yog li ntawd, lub caij nplooj ntoos hlav uas nws qhov tawv thiab qhov loj tuaj yeem raug kho tau——Pob zeb diamond-puab nplooj caij nplooj ntoos hlav hlua. Lub pob zeb diamond-puab nplooj caij nplooj ntoos hlav hlua (Daim duab 15) yog tsim los ntawm ntau lub pob zeb diamond-puab nplooj springs txuas nrog hauv series. Nws muaj cov yam ntxwv ntawm kev tsim qauv dawb thiab qib siab ntawm kev hloov kho. Nws cov thev naus laus zis ua tau zoo ib yam nrog cov pob khawm hloov tau yooj yim, thiab ob qho tib si tau ua tiav los ntawm kev txiav hlau precision.

3.1 Load-tsav qauv ntawm pob zeb diamond-puab nplooj caij nplooj ntoos hlav hlua

Vim lub symmetry ntawm lub rhombic nplooj caij nplooj ntoos hlav, tsuas yog ib lub caij nplooj ntoos hlav yuav tsum tau raug kev nyuaj siab tsom xam, raws li qhia nyob rau hauv daim duab 16. α yog lub kaum sab xis ntawm lub reed thiab kab rov tav, qhov ntev, dav thiab thickness ntawm lub reed yog Ld, Wd, Td raws, f yog lub dimensionally unified load ntawm lub rhombus nplooj hlav,δy yog deformation ntawm rhombic nplooj caij nplooj ntoos hlav nyob rau hauv y kev taw qhia, quab yuam fy thiab lub sij hawm m yog sib npaug loads nyob rau hauv lub kawg ntawm ib tug reed, fv thiab fw yog tivthaiv rog ntawm fy nyob rau hauv lub wov coordinate system.

Raws li lub beam deformation txoj kev xav ntawm AWTAR [13], lub dimensionally unified load-tsav kev sib raug zoo ntawm ib tug reed

Vim qhov kev sib raug zoo ntawm lub cev nruj ntawm lub reed, lub kaum sab kawg ntawm lub reed ua ntej thiab tom qab deformation yog xoom, uas yogθ = 0. Ib leeg (20) (22)

Equation (23) yog lub load-tsav seem kev sib koom ua ke qauv ntawm rhombic nplooj caij nplooj ntoos hlav. n2 rhombic nplooj springs yog kev cob cog rua nyob rau hauv series, thiab nws load-tsav qauv yog

Los ntawm formula (24), thaumαThaum d yog me me, qhov nruj ntawm lub pob zeb diamond-zoo li nplooj nplooj hlav hlua yog kwv yees li kab raws li qhov ntev thiab raug loads.

3.2 Finite element simulation pov thawj ntawm tus qauv

Lub finite caij simulation pov thawj ntawm lub load-tsav qauv ntawm lub pob zeb diamond-puab nplooj hlav yog nqa tawm. Siv ANSYS Mechanical APDL 15.0, cov kev simulation tsis tau qhia hauv Table 2, thiab lub siab ntawm 8 N yog siv rau lub pob zeb diamond-zoo li nplooj hlav.

Table 2 Finite element simulation tsis ntawm rhombic nplooj caij nplooj ntoos hlav hlua

parameter

Ntaus

Khoom siv

AL7075-T6

Reed ntev L

Yab

/ hli

18

Reed Wid W

Yab

/ hli

10

Reed Thickness T

Yab

/ hli

0.25

reed inclination kaum sab xisα/°
10/20/30/40

Elastic Modulus E/GPa

73

Kev sib piv ntawm cov qauv kev tshwm sim thiab cov txiaj ntsig simulation ntawm rhombus nplooj caij nplooj ntoos hlav load-tsav kev sib raug zoo yog qhia hauv daim duab. 17 (dimensionalization). Rau plaub rhombus nplooj springs nrog sib txawv inclination ces kaum, tus txheeb ze yuam kev ntawm tus qauv thiab lub finite caij simulation tshwm sim tsis tshaj 1.5%. Qhov tseeb thiab qhov tseeb ntawm tus qauv (24) tau raug txheeb xyuas.

4 Tsim thiab kev sim ntawm xoom-nrawm flexible pob khawm

4.1 Parameter tsim ntawm xoom-stiffness saj zawg zog pob khawm

Txhawm rau tsim ib qho xoom-qhib pob khawm yooj yim, tus qauv tsim ntawm lub pob khawm hloov tau yuav tsum tau txiav txim siab raws li cov kev pabcuam ua ntej, thiab tom qab ntawd qhov cuam tshuam tsis zoo ntawm crank caij nplooj ntoos hlav mechanism yuav tsum tau xam inversely.

4.1.1 Flexible pob khawm tsis muaj

Qhov kev sib tshuam ntawm lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim yog nyob ntawm 12.73% ntawm qhov ntev reed, thiab nws cov kev txwv tau qhia hauv Table 3. Hloov mus rau hauv kev sib npaug (2), lub torque-rotation lub kaum sab xis kev sib raug zoo ntawm lub puab thiab sab nplhaib hloov tau yooj yim hinges yog

Table 3 Cov yam ntxwv tsis zoo thiab cov khoom siv ntawm lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim hinges

parameter

Ntaus

Khoom siv

AL7075-T6

Reed ntev L / mm

46

Reed dav W / mm

9.4

Reed Thickness T / hli

0.30

Elastic Modulus E/GPa

73

4.1.2 Tsis zoo tawv tawv mechanism tsis

Raws li qhia hauv daim duab. 18, noj tus naj npawb n ntawm crank caij nplooj ntoos hlav mechanisms nyob rau hauv parallel li 3, qhov ntev l = 40 mm yog txiav txim los ntawm qhov loj ntawm lub pob khawm hloov tau. raws li qhov xaus ntawm ntu 2.4, lub kaum sab xis pib =π, crank length ratio = 0.2. Raws li kev sib npaug (16), qhov nruj ntawm lub caij nplooj ntoos hlav (I.e. pob zeb diamond nplooj caij nplooj ntoos hlav hlua) yog Kconst = 558.81 N / m (26)

4.1.3 Pob zeb diamond nplooj caij nplooj ntoos hlav hlua tsis

Luas = 40 mm, =π, = 0.2, thawj qhov ntev ntawm lub caij nplooj ntoos hlav yog 48mm, thiab qhov siab tshaj plaws deformation (& gamma; = 0) yog 16mm. Vim muaj kev txwv cov txheej txheem, nws yog ib qho nyuaj rau ib lub caij nplooj ntoos hlav rhombus los tsim xws li ib tug loj deformation. Siv plaub rhombus nplooj springs nyob rau hauv series (n2 = 4), qhov nruj ntawm ib lub rhombus nplooj hlav yog

Kd=4Kconst=2235.2 N/m (27)

Raws li qhov luaj li cas ntawm qhov tsis zoo tawv tawv mechanism (Daim duab 18), muab lub reed ntev, dav thiab reed inclination lub kaum sab xis ntawm lub pob zeb diamond-puab nplooj hlav, lub reed tuaj yeem txiav tawm los ntawm cov mis (23) thiab cov qauv nruj (27) ntawm lub pob zeb diamond-puab nplooj hlav Thickness. Cov txheej txheem tsis sib xws ntawm rhombus nplooj springs tau teev nyob rau hauv Table 4.

nto4

Nyob rau hauv cov ntsiab lus, qhov tsis ntawm lub xoom-stiffness saj zawg zog pob khawm raws li lub crank caij nplooj ntoos hlav mechanism tau tag nrho cov tau txiav txim, raws li qhia nyob rau hauv Table 3 thiab Table 4.

4.2 Tsim thiab ua cov qauv xoom-qhib hloov pob khawm Xa mus rau cov ntaub ntawv [8] rau kev ua thiab kev sim cov txheej txheem ntawm lub pob khawm hloov tau. Lub xoom-stiffness saj zawg zog pob khawm yog tsim los ntawm qhov tsis zoo nruj mechanism thiab lub nplhaib puab thiab sab nraud hloov tau pob khawm nyob rau hauv parallel. Tus qauv tsim muaj nyob rau hauv daim duab 19.

Ob lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim hinges thiab pob zeb diamond-puab nplooj hlav hlua yog ua tiav los ntawm precision hlau-txiav tshuab cuab yeej. Lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim hinges tau ua tiav thiab sib sau ua ke hauv txheej. Daim duab 20 yog daim duab ntawm lub cev ntawm peb pawg ntawm pob zeb diamond-zoo li nplooj nplooj hlav hlua, thiab Daim duab 21 yog qhov sib dhos xoom-nruj Daim duab lub cev ntawm cov qauv pob khawm hloov tau.

4.3 Lub rotational stiffness test platform ntawm xoom-stiffness saj zawg zog pob khawm Xa mus rau txoj kev rotational stiffness test method nyob rau hauv [8], rotational stiffness test platform ntawm xoom-stiffness saj zawg zog pob khawm yog tsim, raws li qhia hauv daim duab 22.

4.4 Kev sim ua cov ntaub ntawv thiab kev soj ntsuam yuam kev

Kev sib hloov ntawm lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim hinges thiab xoom-stiffness saj zawg zog hinges tau sim ntawm lub platform xeem, thiab cov txiaj ntsig kev sim tau pom hauv daim duab 23. Xam thiab kos qhov xoom-nruj zoo nkhaus ntawm xoom-stiffness saj zawg zog pob khawm raws li cov qauv (19), raws li qhia hauv daim duab. 24.

Cov txiaj ntsig kev sim qhia tau hais tias qhov kev sib hloov nruj ntawm xoom-qhib lub pob khawm hloov tau ze rau xoom. Piv nrog rau sab hauv thiab sab nraud lub nplhaib hloov tau yooj yim, lub pob khawm xoom-qhib saj zawg zog±0.31 hli (18°) nruj tau txo los ntawm qhov nruab nrab ntawm 93%; 0.26 hli (15°), qhov tawv nqaij yog txo los ntawm 90%.

Raws li tau pom nyob rau hauv daim duab 23 thiab 24, tseem muaj qhov sib txawv ntawm qhov kev xeem ntawm qhov xoom txhav zoo thiab cov qauv kev xav tau (qhov kev txheeb ze yuam kev tsawg dua 15%), thiab cov laj thawj tseem ceeb ntawm qhov yuam kev yog raws li hauv qab no.

(1) Tus qauv yuam kev tshwm sim los ntawm qhov yooj yim ntawm kev ua haujlwm trigonometric.

(2) Kev sib txhuam. Muaj kev sib txhuam ntawm pob zeb diamond nplooj caij nplooj ntoos hlav hlua thiab cov ncej mounting.

(3) Kev ua yuam kev. Muaj qhov yuam kev nyob rau hauv qhov loj ntawm lub reed, thiab lwm yam.

(4) Kev sib dhos yuam kev. Qhov sib txawv ntawm qhov kev teeb tsa ntawm lub pob zeb diamond-zoo li nplooj nplooj hlav hlua thiab cov ncej, qhov sib txawv ntawm qhov kev sim platform ntaus ntawv, thiab lwm yam.

4.5 Kev sib piv kev ua tau zoo nrog ib qho xoom-qhib hloov tau yooj yim pob khawm Hauv cov ntaub ntawv [4], xoom-stiffness saj zawg zog pob khawm ZSFP_CAFP tau tsim los siv tus ntoo khaub lig-axis flexural pivot (CAFP), raws li qhia hauv daim duab 25.

Kev sib piv ntawm xoom-nrawm hloov pob khawm ZSFP_IORFP (Fig. 21) thiab ZSFP_CAFP (Fig. 25) tsim los siv lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim hinges

(1) ZSFP_IORFP, tus qauv yog compact dua.

(2) Lub kaum sab xis ntawm ZSFP_IORFP yog me me. Lub kaum sab xis yog txwv los ntawm lub kaum sab xis ntawm lub pob khawm hloov tau nws tus kheej; lub kaum sab xis ntawm ZSFP_CAFP80°, ZSFP_IORFP kaum ntau yam40°.

(3) ±18°Hauv qhov ntau ntawm cov ces kaum, ZSFP_IORFP muaj qhov zoo dua ntawm xoom txhav. Qhov nruab nrab nruj ntawm ZSFP_CAFP yog txo los ntawm 87%, thiab qhov nruab nrab qhov tawv nqaij ntawm ZSFP_IORFP yog txo los ntawm 93%.

5 xaus

Siv lub pob khawm hloov pauv ntawm lub nplhaib sab hauv thiab sab nraud nyob rau hauv cov ntshiab torque raws li qhov zoo txhav subsystem, cov haujlwm hauv qab no tau ua tiav txhawm rau txhawm rau tsim lub pob khawm xoom-qhib saj zawg zog.

(1) Tshaj tawm qhov tsis zoo qhov tawv tawv sib hloov tshuab——Rau lub crank caij nplooj ntoos hlav mechanism, ib tug qauv (Formula (6)) yog tsim los soj ntsuam cov yam ntxwv ntawm cov yam ntxwv tsis zoo ntawm nws cov yam ntxwv tsis zoo, thiab qhov ntau ntawm nws cov yam ntxwv tsis zoo tawv nqaij tau muab (Table 1).

(2) Los ntawm kev sib piv qhov zoo thiab qhov tsis zoo, cov yam ntxwv nruj ntawm lub caij nplooj ntoos hlav hauv crank caij nplooj ntoos hlav mechanism (Equation (16)) tau txais, thiab tus qauv (Sib npaug (19)) yog tsim los tshuaj xyuas qhov cuam tshuam ntawm cov qauv tsis. ntawm lub crank caij nplooj ntoos hlav mechanism ntawm xoom stiffness zoo ntawm xoom stiffness saj zawg zog pob khawm Influence, theoretically, nyob rau hauv lub muaj mob stroke ntawm lub saj zawg zog pob khawm ntawm lub puab thiab sab rings (±20°), qhov nruab nrab txo qhov nruj tuaj yeem ncav cuag 97%.

(3) Tshaj tawm qhov tawv tawv tuaj yeem kho tau“Ntaus”——Lub pob zeb diamond-zoo li nplooj nplooj hlav hlua tau tsim los tsim kom muaj nws cov qauv nruj (Equation (23)) thiab txheeb xyuas los ntawm finite element method.

(4) Ua tiav cov qauv tsim, ua tiav thiab kev sim ntawm cov qauv xoom-nruj hloov pauv pob khawm. Cov txiaj ntsig kev sim qhia tau hais tias: nyob rau hauv qhov kev txiav txim ntawm ntshiab torque, lub36°Nyob rau hauv qhov ntau ntawm kev sib hloov lub kaum sab xis, piv nrog lub nplhaib sab hauv thiab sab nraud hloov tau yooj yim, qhov nruj ntawm xoom-qhib pob khawm hloov tau raug txo los ntawm 93% ntawm qhov nruab nrab.

Lub tsim xoom-stiffness saj zawg zog pob khawm tsuas yog nyob rau hauv qhov kev txiav txim ntawm ntshiab torque, uas tuaj yeem paub.“tsis muaj zog”, tsis xav txog cov ntaub ntawv ntawm cov kabmob complex loading tej yam kev mob. Yog li ntawd, kev tsim kho ntawm xoom-stiffness saj zawg zog hinges nyob rau hauv complex load tej yam kev mob yog lub hom phiaj ntawm kev tshawb fawb ntxiv. Tsis tas li ntawd, txo cov kev sib txhuam uas tshwm sim thaum lub sij hawm txav ntawm xoom-nruj saj zawg zog hinges yog ib qho tseem ceeb optimization kev taw qhia rau xoom-stiffness saj zawg zog hinges.

cov ntaub ntawv

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[2] Yu Jingjun, Pei Xu, Bi Shusheng, thiab lwm yam. Kev tshawb nrhiav kev nce qib ntawm kev tsim qauv ntawm lub pob khawm yooj yim [J]. Suav Journal of Mechanical Engineering, 2010, 46(13:2-13. Y u jin champion, PEI X U, BIS call, ETA up. State-of-arts of Design Method for Flexure Mechanisms[J]. Phau ntawv Journal of Mechanical Engineering, 2010, 46(13:2-13.

[3] MORSCH F M, Herder JL. Tsim ntawm Generic Zero Stiffness Compliant Joint[C]// ASME International Design Engineering Conferences. 2010:427-435.

[4] MERRIAM E G, Howell L. Tsis yog-dimensional mus kom ze rau static ntsuas ntawm rotational flexures [J]. Mechanism & Machine Theory, 2015, 84(84): 90-98.

[5] HOETMER K, Woo G, Kim C, et al. Qhov tsis zoo ntawm lub tsev Blocks rau Statically Balanced Compliant Mechanisms: Design and Testing [J]. Phau ntawv Journal of Mechanisms & Robotics, 2010, 2(4): 041007.

[6] JENSEN B D, Howell L. Tus qauv ntawm cross-axis flexural pivots [J]. Mechanism thiab tshuab theory, 2002, 37(5): 461-476.

[7] WITTRICK W H. Cov khoom ntawm crossed flexure pivots thiab cuam tshuam ntawm qhov taw tes ntawm cov strips hla [J]. Aeronautical Quarterly, 1951, II: 272-292.

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[9] Yang Qizi, Liu Lang, Bi Shusheng, thiab lwm yam. Kev tshawb fawb txog kev sib hloov cov yam ntxwv ntawm qhov dav dav peb-cross reed saj zawg zog pob khawm[J]. Suav Journal of Mechanical Engineering, 2015, 51(13): 189-195.

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Txog tus sau: Bi Shusheng (tus sau sau), txiv neej, yug xyoo 1966, kws kho mob, tus xibfwb, tus kws saib xyuas tus kws kho mob. Nws txoj kev tshawb fawb tseem ceeb yog qhov hloov pauv tau yooj yim thiab cov neeg hlau bionic.

AOSITE Hardware ib txwm ua raws li peb lub ntsiab lus ntawm "kev ua tau zoo ua ntej" los ntawm kev tsom mus rau kev tswj kom zoo, txhim kho kev pabcuam, thiab cov lus teb sai.
AOSITE Hardware tau mob siab rau kev txhim kho, kev tsim khoom, kev lag luam thiab kev muag khoom txij li thaum nws pib.Our kev koom tes tenet yog .Hinge muaj feem xyuam rau ntau yam xws li zaub mov thiab dej haus, tshuaj, khoom siv txhua hnub, khoom siv hauv tsev so, khoom siv hlau, kev ua liaj ua teb, tshuaj, electronics, thiab machinery.
Nrog rau kev siv vuam, txiav, polishing, thiab lwm yam kev siv tshuab ntau lawm thiab cov neeg ua haujlwm txhawb nqa, AOSITE Hardware cog lus rau cov khoom tsis zoo thiab cov kev pabcuam zoo rau cov neeg siv khoom.

1. Kev siv tshuab ntau lawm: Nrog ntau xyoo ntawm kev sib sau, peb muaj peev xwm txaus los txhim kho cov txheej txheem ntau lawm. Kev siv thev naus laus zis suav nrog vuam, tshuaj etching, nto blasting, thiab polishing pab txhawb rau kev ua tau zoo ntawm cov khoom.
Peb lub tuam txhab Drawer Slides yog nruj me ntsis tsim los ntawm ib tug xov tooj ntawm kev ua cov txheej txheem, thiab lawv ua tau raws li lub teb chaws cov qauv kev soj ntsuam zoo. Rau ib yam, peb cov khoom yog nyob rau hauv txoj kab nrog niaj hnub zoo nkauj, nrog stylish thiab zoo tsos thiab kev ua tau zoo heev. Rau lwm yam, lawv tsis yooj yim rau xeb thiab khawb, muaj zog tiv thaiv corrosion thiab muaj peev xwm tiv thaiv xeb. Raws li tag nrho cov nta, peb cov khoom tsim nyog rau sab hauv tsev thiab sab nraum zoov.AOSITE Hardware tau ua tiav hauv . Ntau xyoo dhau los, peb tau kawm tas li cov khoom siv hluav taws xob tsim khoom los ntawm kev lag luam zoo heev. Lub caij no, peb tau tsim kev sib raug zoo thiab kev koom tes ntev nrog ntau lub tuam txhab. Peb tau txhim kho peb lub tuam txhab kev cuam tshuam zoo heev.Yog tias qhov rov qab los yog los ntawm cov khoom zoo lossis qhov yuam kev los ntawm peb, koj yuav raug lees paub kom tau txais 100% cov nyiaj rov qab.

Thaum ua kev tshawb fawb ntawm Zero Stiffness Flexible Hinge raws li Crank Spring Mechanism, nws yog ib qho tseem ceeb kom nkag siab txog lub tswv yim ntawm kev paub txog pob khawm thiab nws daim ntawv thov hauv engineering thiab tsim. Nov yog qee cov lus nug uas nquag nug txog lub ncauj lus no.

Lub qhov rooj pob khawm yog ib qho tseem ceeb accessories ntawm lub qhov rooj. Nws txuas lub qhov rooj thiab lub qhov rooj ncej thiab tso cai rau peb qhib thiab kaw lub qhov rooj smoothly