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Thesis - Leigh Moody.pdf - Bad Request - Cranfield University

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Chapter 5 / Missile State Observer<br />

_ _<br />

∂ F<br />

∂ X<br />

B<br />

m<br />

ML<br />

: =<br />

⎛<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎝<br />

m<br />

−1<br />

m<br />

∂ y<br />

∂ X<br />

∂ z<br />

∂ X<br />

⎛<br />

⋅ ⎜<br />

⎝<br />

v<br />

ML<br />

w<br />

ML<br />

∂ F<br />

∂ X<br />

⋅ P&<br />

⋅ P&<br />

XB<br />

T<br />

ML<br />

YB<br />

o,<br />

m<br />

ZB<br />

o,<br />

m<br />

5-25<br />

∂ F<br />

+<br />

∂ X<br />

∂ y<br />

+<br />

∂ X<br />

∂ z<br />

+<br />

∂ X<br />

XB<br />

D<br />

ξ<br />

ML<br />

η<br />

ML<br />

ML<br />

⋅ ξ<br />

⋅ η<br />

⎞ ⎞<br />

⎟ ⎟<br />

⎟<br />

⎠ ⎟ ⎛<br />

⎟ ⎜<br />

⎟ ⎜<br />

⎟ ⎜<br />

+<br />

⎟ ⎜<br />

y<br />

⎟ ⎜<br />

⎟ ⎜<br />

⎟ ⎝<br />

z<br />

⎟<br />

⎠<br />

v<br />

w<br />

⋅<br />

⋅<br />

0<br />

456 B ( ϕ )<br />

A<br />

⎞<br />

( ) ⎟ ⎟⎟⎟⎟⎟⎟<br />

789 B T<br />

ϕ<br />

A<br />

T<br />

⎠<br />

Equation 5.9-25<br />

The variation in thrust and drag with respect to the linear missile states is<br />

defined in §6.3&4. The normalised lateral force derivatives are themselves<br />

functions of Mach Number, geodetic height and incidence. For example,<br />

the variation in the lateral lift derivative with respect to the these parameters<br />

expressed in the state space,<br />

⎛<br />

⎜<br />

⎜<br />

⎝<br />

0<br />

2<br />

,<br />

∂ y<br />

∂ M<br />

v<br />

m<br />

∂ M<br />

⋅<br />

∂ P<br />

m<br />

ZA<br />

m<br />

M<br />

∂ y<br />

v<br />

∂ y<br />

∂ M<br />

v<br />

∂ X<br />

m<br />

ML<br />

∂ M<br />

⋅<br />

∂ P&<br />

: =<br />

m<br />

A<br />

m<br />

+<br />

∂ y<br />

∂ ξ<br />

v<br />

MV<br />

B<br />

MV<br />

∂ ξB<br />

⋅<br />

∂ P&<br />

A<br />

m<br />

M<br />

0<br />

3<br />

⎞<br />

⎟<br />

⎟<br />

⎠<br />

Equation 5.9-26<br />

Likewise for the other normalised aerodynamic derivatives. For the generic<br />

missile, these equations are simplified using the incidence lag and its<br />

variation with missile height, velocity and incidence that are defined in §6,<br />

∂ F<br />

∂ X<br />

B<br />

m<br />

ML<br />

: =<br />

⎛<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎜<br />

⎝<br />

−1<br />

m<br />

⎛<br />

⋅ ⎜<br />

⎝<br />

∂<br />

−<br />

∂ F<br />

∂ X<br />

YB ( 1 T )<br />

∂ X<br />

ZB ( 1 T )<br />

∂<br />

−<br />

∂ X<br />

XB<br />

T<br />

ML<br />

I<br />

ML<br />

I<br />

ML<br />

∂ F<br />

+<br />

∂ X<br />

⋅ P&<br />

⋅ P&<br />

XB<br />

D<br />

ML<br />

YB<br />

o,<br />

m<br />

ZB<br />

o,<br />

m<br />

5.9.3.2 Angular Motion Pseudo-Measurements<br />

m<br />

⎞<br />

⎟<br />

⎠<br />

⎞<br />

⎟<br />

⎟<br />

⎟<br />

⎟<br />

⎟<br />

⎟<br />

⎟<br />

⎟<br />

⎟<br />

⎟<br />

⎠<br />

⎛<br />

⎜<br />

⎜<br />

⎜<br />

− ⎜<br />

⎜<br />

⎜<br />

⎝<br />

YB 456 B<br />

( 1 T ) ⋅ ( ϕ )<br />

I<br />

( ) ( ) ⎟ ⎟⎟⎟⎟⎟⎟<br />

ZB 789 B T<br />

1 T ⋅ ϕ<br />

I<br />

0<br />

A<br />

A<br />

T<br />

⎞<br />

⎠<br />

Equation 5.9-27<br />

Applying the simplifying assumptions to the angular equations of motion<br />

the angular acceleration pseudo-measurement,

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