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

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Chapter 6 / Missile Guidance<br />

_ _<br />

B<br />

A<br />

D T<br />

D T<br />

( π , ϕ ( Θ , ζ , ω ) , ϕ ( Ψ , ζ , ) )<br />

E : =<br />

ω<br />

NO<br />

D2L<br />

A<br />

INDEXS = 1<br />

YES<br />

LAUNCH = 1<br />

MS_LONGAX<br />

6-34<br />

L<br />

LAUNCHER (P,Y) 2ND<br />

ORDER DYNAMICS<br />

OPERATING ON TARGET<br />

POSITION MAPPED TO<br />

MISSILE BODY AXES<br />

ALIGNMENT TO MISSILE<br />

EULER TO QUATERNION<br />

AVERAGE ANGULAR<br />

MISSILE BODY RATE<br />

AVERAGE ANGULAR<br />

ACCELERATION BY 1ST<br />

ORDER DIFFERENCING<br />

YES<br />

YES<br />

L<br />

D2L<br />

( 4 KHZ )<br />

MS_LAUNCHER<br />

LAUNCH < 2<br />

MS_LONGAX<br />

ALIGNMENT<br />

REFERENCED SPECIFIC<br />

ACCELERATION<br />

ALIGNMENT<br />

REFERENCED INERTIAL<br />

ACCELERATION<br />

( INDEXI = 1)<br />

MS_ROTATE<br />

MISSILE QUATERNION<br />

STATE DERIVATIVES<br />

ALIGNMENT<br />

REFERENCED SPECIFIC<br />

ACCELERATION<br />

Figure 6-11 : Launcher Simulation<br />

A<br />

L<br />

L<br />

Equation 6.9-1<br />

If the launcher bandwidth is set to zero its dynamics are by-passed and the<br />

missile is pointed at the selected tracking point,<br />

E<br />

M<br />

A<br />

: =<br />

E<br />

B<br />

A<br />

+<br />

( π , 0 , 0 )<br />

Equation 6.9-2<br />

In the launcher (LAUNCH < 2) the Missile Velocity and Seeker Head<br />

frames are aligned with the Missile Body frame. The missile angular rate<br />

and acceleration are determined from its current and previous orientation,<br />

and by numerical differences at 4 kHz. Once the missile is clear of the<br />

launcher the system state is propagated according to the equations presented<br />

in §6.10.2.

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