Research Article Volume 7 Issue 1
National Research University of Electronic Technology, MIET, Russia
Correspondence: Afonin SM, National Research University of Electronic Technology, MIET, 124498, Moscow, Russia
Received: April 17, 2023 | Published: April 26, 2023
Citation: Afonin SM. Structural model of nano piezoengine for applied biomechanics and biosciences. MOJ App Bio Biomech. 2023;7(1):21-25. DOI: 10.15406/mojabb.2023.07.00171
The structural model of the nano piezoengine is determined for applied biomechanics and biosciences. The structural scheme of the nano piezoengine is obtained. For calculation nano systems the structural model and scheme of the nano piezoengine are used, which reflect the conversion of electrical energy into mechanical energy of the control object. The matrix equation is constructed for the nano piezoengine in applied biomechanics and biosciences.
Keywords: nano piezoengine, structural model, applied biomechanics and biosciences
The nano piezoengine based on the inverse piezoeffect is used for applied biomechanics and biosciences, nanomedicine, nanobiology, microsurgery. The nano piezoengine is provided for applied biomechanics and biosciences in scanning probe microscopy, interferometers and adaptive optics, actively dampen vibrations, deform mirrors and the work with the genes.1–6
For calculation nano systems the structural model and scheme of the nano piezoengine are used, which reflect the conversion of electrical energy into mechanical energy of the control object.6–19
Structural model
For calculation the nano piezoengine on Figure 1 is determined the inverse piezoeffect.1–49
Si= d mi Em+s E ij Tj
here d mi,s E ij,Em,Tj,Si are piezomodule, elastic compliance, strength electric field, strength mechanical field, relative deformation.
For the nano piezoengine the differential equation is evaluated4–56
d2 Ξ (x,s)dx2 − γ2 Ξ (x,s)=0
here Ξ(x,s),x,s,γ are the transform of deformation, the coordinate, the parameter of transform, the factor of propagation.
For the longitudinal piezoengine at x=0 the deformation Ξ(0,s)=Ξ1(s) , at x=δ,Ξ(δ,s)=Ξ2(s) are calculated.
Its solution is written4–36
Ξ (x,s)={ Ξ1 (s) sh [ (δ−x) γ]+Ξ2(s)sh(xγ)}/sh(δγ)
For the nano longitudinal piezoengine in Figure 1 its relative displacement on 3 axes1–29 has the form
S3= d33 E3+s E33 T3
The system for the nano longitudinal piezoengine is obtained11–31 for x=0,x=δ
T3(0,s)=1s E33 d Ξ (x,s)dx |x=0−d 33s E33E3(s)
T3 (δ,s) = 1s E33 d Ξ (x,s)dx |x=δ− d33s E33 E3 (s)
The structural model is evaluated for applied biomechanics and biosciences
Ξ1(s)=(M1s2)−1{ −F1(s)+( χE33 ) −1 × [ d33 E3 (s)−[γ / sh ( δγ ) ] × [ch( δγ )Ξ1(s)−Ξ2(s)]] }Ξ2 (s) = (M2s2)−1 { − F2 (s) + (χ E33 ) −1 × [ d33 E3 (s) − [ γ / sh ( δγ ) ] × [ ch ( δγ ) Ξ2 ( s ) − Ξ1 (s) ] ] }χ E33 = s E33 / S0
here Ξ1(s),Ξ2(s) - the transformations of displacements, S0 - the area.
For the nano transverse piezoengine the expression of the transverse inverse piezoeffect1–29
S1= d31 E3+ s E11 T1
The system for the nano transverse piezoengine is determined for x=0 and x=h
T1 (0,s)= 1s E11 d Ξ (x,s)dx |x=0− d 31s E11 E3 (s)T1 (h,s) = 1sE11 d Ξ (x,s)dx |x=h− d31sE11 E3 (s)
The structural model of the nano transverse piezoengine is calculated
Ξ1 (s) = ( M1s2 )−1 { − F1 (s)+ ( χ E11 )−1 × [ d31 E3(s) − [γ / sh ( hγ ) ] × [ch(hγ ) Ξ1(s)− Ξ2( s )]] }Ξ 2 (s) = ( M2 s2 )−1{ − F2 (s) + ( χ E11 ) −1 × [ d31 E3(s)− [ γ / sh ( hγ ) ] × [ch( hγ ) Ξ 2 ( s )−Ξ 1 ( s ) ] ] }χ E11 = s E11 / S0
For the nano shift piezoengine the expression of the shift inverse piezo effect1–29
S5=d15 E1+s E55 T5
The system for the shift piezoengine is written at x=0 and x=b
T5 (0, s)= 1s E55 d Ξ (x,s)dx | x=0− d 15s E55 E1 (s)T5 (b,s)=1s E55d Ξ ( x,s ) dx | x=b − d 15s E55 E1 (s)
The structural model is calculated
Ξ1( s )= ( M1 s2 )−1 { − F1 ( s )+ ( χ E55 ) −1 × [d 15 E 1( s )− [ γ/ sh ( b γ ) ] ×[ch(bγ)Ξ1( s )− Ξ 2 ( s ) ]] }Ξ 2 ( s )= ( M2s2 ) −1 { −F2 ( s )+ ( χ E55 ) −1 × [ d 15 E 1 ( s )− [ γ / sh ( bγ ) ]× [ch( bγ )Ξ2(s)− Ξ 1 ( s ) ] ] }χ E55 = s E55 / S 0
At x=0 and x=l for l={ δ, h, b the system in general is obtained
Tj(0,s)= 1sΨ ij d Ξ (x,s)dx |x=0− ν misΨ ij Ψm (s)Tj(l,s)= 1sΨ ij d Ξ (x,s) dx |x=l− ν misΨ ij Ψm (s)
The structural model and scheme of the nano piezoengine on Figure 2 are evaluated
Ξ1(s)=(M1s2)−1{−F 1 (s)+(χ Ψ ij ) −1× [ν mi Ψ m (s)−[ γ / sh (lγ) ]× [ch(lγ)Ξ1(s)−Ξ2(s)]] }
Ξ 2(s)=(M2 s2)−1{ −F 2(s)+(χ Ψ ij ) −1× [νmiΨm(s)−[ γ / sh ( lγ ) ]× [ ch (lγ)Ξ 2 (s)−Ξ 1 (s)]]}
χ Ψij = s Ψij / S0
v mi = { d 33 , d 31 , d 15 g 33 , g 31 , g 15
Ψ m = { E 3 , E 3 , E 1 D 3 , D 3, D 1
s Ψ ij = { s E 33 , s E 11 , s E 55 s D 33 ,s D 11 , s D 55
γ={γE, γD
c Ψ={ c E, c D
The displacements matrix is calculated
(Ξ1(s)Ξ2(s))=(W 11 (s)W 12 (s)W 13 (s)W 21 (s)W 22 (s)W 23 (s)) (Ψm(s)F1(s)F2(s))
W11(s)=Ξ1(s)/Ψm(s)=ν mi [M2χ Ψ ij s2+γ th (lγ/2)]/A ij
A ij =M1M2(χ Ψ ij )2s4+{(M1+M2)χΨ ij /[cΨ th (lγ)]} s3+[(M1+M2)χ Ψ ij α/ th (lγ)+1/(cΨ)2]s2+2αs/cΨ+α2
W 21 (s)=Ξ2(s)/Ψm(s)=ν mi [M1χ Ψ ij s2+γ th (lγ/2)]/A ij
W 12 (s)=Ξ1(s)/F 1(s)=−χ Ψ ij [M 2 χ Ψ ij s2+γ / th (lγ)]/ A ij
W 13 (s)=Ξ1(s)/F 2(s)=W 22 (s)=Ξ2(s)/F 1(s)=[χ Ψ ij γ/ sh (lγ)]/ A ij
W 23 (s)=Ξ2(s)/F 2 (s)=−χ Ψ ij [M1 χ Ψ ij s2+γ/ th (lγ)]/ A ij
The static longitudinal displacements are evaluated
ξ1=d 33 U M2 / (M1+M2)ξ2=d 33 U M 1 / (M1+M2)
For d 33 = 4⋅10−10m/V , U = 25 V, M1 = 1 kg, M2 = 4 kg the static displacements ξ1 = 8 nm, ξ2 = 2 nm and ξ1+ξ2 = 10 nm are evaluated at error 10%.
The equation of the direct piezo effect is used1–29
D m= dmi Ti + ε Emk E kk d= d mi S0δ s Eij
here ε Emk,Dm,kd - the permittivity, the electric induction and the direct coefficient. The transform the voltage of feedback for the nano piezoengine on Figure 3 is calculated
Ud(s)=d mi S0 Rδs Eij •Ξn (s)= kd R •Ξn (s),n=1, 2
For the nano piezoengine its static deformation is obtained.
For voltage control
Tjmax= Em dmi / s EijFmax= Em d mi S 0 / s Eij
For current control
Fmax=Uδ d mi S 0s Eij+ F maxS0 d mi S c 1ε Tmk S c/ δ 1δ d mi S 0s EijFmaxS0 ( 1− d 2miε Tmk s Eij )s Eij=E m d mi Tjmax ( 1−k 2mi ) s Eij=E m d mik mi =d mi /√ s Eij ε Tmk
here Sc,C0,k mi - the sectional area of capacitor, the capacitance, and the coefficient of electromechanical coupling.
For current control of the nano piezoengine
Tj max=E m d mi / s DijFmax=E m d mi S 0 / s Dijs D ij = (1− k 2 mi ) s E ij
The mechanical characteristic of the nano piezoengine is obtained
Δl=Δlmax(1−F/Fmax)Δl max= ν mi Ψ m lFmax=Tj maxS0= ν mi Ψ m S0 / s Ψij
The expression of the mechanical characteristic of the nano transverse piezoengine is calculated
Δh=Δhmax(1−F/Fmax)Δhmax=d 31 E3hF max=d 3 1 E 3 S 0 / s E1 1
At d 3 1 = 2⋅10−10m/V , E3 = 0.5∙105 V/m, h = 2.5∙10-2 m, S0 = 1.5∙10-5 m2, s E1 1 = 15∙10-12 m2/N the parameters Δhmax = 250 nm, Fmax = 10 N are obtained on Figure 4 at error 10%.
The deformation piezoengine at elastic load is obtained
Δll = ν mi Ψm− s Ψij CeS0 ΔlF=Ce Δl
The control characteristic of the nano piezoengine is determined
Δl= ν mi l Ψm1+ C e / C Ψ ijs ij = ks s E ij ,( 1− k 2mi )≤ks≤1
here ks the coefficients change of elastic compliance.
For the nano piezoengine its reverse and direct coefficients are calculated
kr=kd= d mi S0δ s ij
By using the equation of load the scheme of the nano piezoengine with one fixed face on Figure 5 is calculated.
The expression on voltage for Figure 4 is calculated
W(s)=Ξ2(s)/U(s)=kr/N(s)N(s)=a0 s3+a1 s2+a2 s+a3a0=R C0 M2,a1 =M2+ R C0 kva2=kv+R C0 C ij + R C0 C+e R kr kd,a 3= C e+ Cij
here kv - the coefficient of damping.
For the nano transverse piezoengine for R=0 the expression on voltage is determined
W (s)= Ξ (s)U (s)=k U31 T2t s2+2Tt ξt s+1k U31 =d 31 (h/δ)/( 1+C l/C E11)Tt= √M /( C l + C E1 1 ),ωt=1/ Tt
For M = 2 kg, Cl = 0.2⋅107N/m , C E11 =1.6⋅107N/m the parameters Tt = 0.33×10-3 s, ωt =3 ⋅10 3 s −1 are evaluated on Figure 6 at error 10%.
The static displacement
Δh=d 31 (h/δ)U1+Cl /C E11=k U31 U
For d 31 = 2⋅10−10m/V , h/δ = 24, Cl /C E11 = 0.1 the parameter k U31 = 4.4 nm/V is evaluated at error 10%.
For calculation nano systems the structural model and scheme of the nano piezoengine are used, which reflect the conversion of electrical energy into mechanical energy. The structural model and schemes of the nano piezoengine are obtained for applied biomechanics and biosciences. The matrix of the deformations of the nano piezoengine is constructed. The parameters of the nano piezoengine are determined for applied biomechanics and biosciences.
None.
None.
The authors declare that they have no conflict of interest.
©2023 Afonin. This is an open access article distributed under the terms of the, which permits unrestricted use, distribution, and build upon your work non-commercially.