principi fisici dei sensori moderni in ambito meccatronico

7/30/2019 PRINCIPI FISICI DEI SENSORI MODERNI IN AMBITO MECCATRONICO

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q

E


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14/65

q1q2 r21

F21 = k

q1q2

r212

ur,

k ur q2k

k =1

40 9 109

N m2C2

,

0

0 8.85 1012 N1m2C2 .


15/65

q

E =

F

q.

N C1

A


16/65

A

A =

A u d.

u

A =

A u d.

A =

E u d =

q

0.

div(E) =

E =

0,

E =

x

i +

y

j +

z

k E =

Ex

x

+Ey

y

+Ez

z

.

1

r2U

q

A B


17/65

UB UA = LAB =

B

A

F dl = q

B

A

E dl.

q

E

V =

U

q .

V =U

q.

[V] =

J C1

VAB =

B

A

E dl ;

E = V =

x

i +

y

j +

z

k

V =

V

x

i +

V

y

j +

V

z

k

.

VA VB =

BA

E d

l = E d,


18/65

d

q

V(r) =1

40

q

r.

E

q

d

p = q d uk,

uk

v(r) =1

40

pcos

r2.


19/65

C =Q

V,

F = C

VC = 0

A

d,

A d


20/65

w =1

20E

2.

W = 12

QV = 12

CV2 = 12

Q2

C.


21/65

I =Q

t,

Q t

t

I =dQ

dt.

A = C s1

J = nevd,

n evd

V = R I,

R = V A1

R = l

,


22/65

l

[W m]

j =

E .

I V

P = V I.

P = V I = R I2 =V2

R.

L R = L

(1.59 2.44) 108 [ m]

T c = 7.18K T c =4.15

T c = 91K

135K

T

,

= 0 [1 + (T T0)] ,

0


23/65

Rt = Rt0exp

1

T

1

T0

,

T0 Rt0

(3000K;5000K)

F = q v

B ,


24/65

F = q

E

dl L

i B

dF = i d

l

B

F = i

L

dl

B = iLB.

dl

i

dB =

0

4i

dl ur

r2,


25/65

r ur0

0 = 4 107 [N]

[A2].

i

r

B(r) =0i

2r.

i1 i2 d

Fl

= 0i1i22d

.

B d

l = 0i,


26/65

i

n

i

B = 0ni

B

(B ) =

B und,

un A

(B ) = B A cos().

= d(

B )

dt.


27/65

(B )

II

(B ) I

L

L =(

B )

I.

I (B )

= LdI

dt,

W = 12

B

2

0.

L

I

W =1

2 L I2.


28/65

I1

I1

21 = M21dI1

dt,

M21

12 = M12dI2

dt ,

I2

M = M12 = M21.

x

f(x, t) = f(x vt),

v

2f

x2=

1

v22f

t2,

f(x vt) = A sin[k(x vt)] = A sin[k x t],

= k v.

= 2k

T = 2

= 1T

= 2

= v


29/65

v = k

v

vg

vg = v +dv

dk k.

E und =

q

0

E =

0.

B und = 0

B = 0.

E utdl =

d

dt

B und

E =

B

t.

B

ds = 0I + 00

d

dt

E und

B = 0

j + 00

E

t.

2E

z2= 00

2Ex

t2,

2B

z2= 00

2By

t2,


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(E B) c = 100

3 108

E = c B

wel =1

20E

2,

wmag =1

2

B2

0,

w = wel + wmag = 0 E2.

S = 1

0

E

B

c v = cn

n

d C = 0

d

E = lib0

lib

r

C = 0r

d

Etot = Eapplicato Epol Epol

P


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D = 0r

Etot

D =

0

Etot +

P P = 0eEtot eD = 0

Etot + 0e

Etot

r = 1 + e E und =

qlib + qpol0

,

qpolD

D und = qlib.

D E D

E

B

H

H

M

B = 0(

H +

M)

H

M = mag

H mag

B = 0(

H + mag

H) = 0r

H r = 1 + mag

B

H

B uNdl = 0(icond + imagn) = 0ricond,

H uNdl = icond,


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icond imagn

B =

0r

4icond

dl ur

r2,

B(r) =0ricond

2r,

B = 0rnicond,

w =B2

20r.

B

H

mag 104 105

mag 105

mag 1010


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20Hz 20kH z 20Hz20kH z

V V V

p

V V

B = pVV

= 0 v2,

0 v

v =

B

0.

B 0

E

v =

E(1 )

0(1 + )(1 2).


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P

.

Z =P

.

Z

Z = 0 v.

I

I = P =P2

Z.

I0 = 1012 W

m2

= 10log10

II0

.

I0

I = I0 = 0


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n = cv

ir = i

n1i

n2 t

n1sini = n2sint.


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n1n2

c

sinc =n2

n1

.

c

c v

f

v = f,


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c = 0f,

0

n =c

v=

0

.

d

D d

= d sin.

= d sin = m,

m = (0, 1, 2, .....)

= d sin = (m +1

2),


38/65

m = (0, 1, 2, .....)

D

ym = mD

d

ym = (m +1

2)

D

d

S

2S = (m +1

2

),

m = (0, 1, 2, .....) n

0 =0n

2nS = (m +1

2)0,

m = (0, 1, 2, .....)

2nS = m0,

m = (0, 1, 2, .....)


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b

bsin = m,

m = (0, 1, 2, .....)


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q = AT

n,

q ATn

TwT

q = A (Tp Tf) .


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A

qrad = A T4,

5.669108

Wm2K4

T1 T2

qradnettaA

= A

T41

T42

.


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f h h

h


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f2E = h f2 h

W0

W0


46/65

f0

V0I

EKMAX

EKMAX = e V0,

I e

1.6 1019C V0

I f >

f0

i

I

E = hf 1 10eV

102eV

f

EK

EK = hf W,

W

EKMAX

EKMAX = hf W0 0,

W0hf0 = W0

f < f0

V0

V0 =hf

e

W0

e,

h

I I


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h

10 mAmW

10ns


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P =

Pxx +

Pyy +

Pzz ,

x y z

Pxx = d11xx + d12yy + d13zz

Pyy = d21xx + d22yy + d23zz

Pzz = d31xx + d32yy + d33zz

dpq CN


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g =dpq0pq

VmN

m2 h = gEY oung

Vm

g

kpq =

dpq hpq.

x

Qx = d11Fx.

C V

V =

Qx

C =

d11

C Fx;

s

C = k0

s,

0 k

V = d11C Fx = d11k0

Fx.


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109 CN

SQ =Q

P,

Q P

V =Q

C =SQ

C P,

V C = CS+CCV

SV =SQ

C=

Q

P C=

Q

P (CS + CC).

SV CC

Q V SV CC


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VU =Q

CR,

CR


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F

F = q v

B ,

q = 1.6 1019C v B

i


54/65

VH

VH = h i B sin,

B

h

H =1

N c q,

N c

q


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Ri

Ro

B

Ri Ro


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dVa = adT

dxdx,

dT dx a

a

dVa = adT.

T

x

f em


59/65

T3 T4 T5

f em T1

T2

ia = ib

f em

i = ia ib

ddp


60/65

A

AB = A B.

dVAB = ABdT.

AB =dVAB

dT.


61/65

giunto freddogiunto caldo

0

dQP = p i dt,

i dt p


62/65

R

P =i2

R.

f.e.m. f.e.m.


63/65

ES = pAB|T2 pAB|T1 +

T2

T1

AdT

T2

T1

BdT =

T2

T1

ABdT,


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principi fisici dei sensori moderni in ambito meccatronico

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