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

Appendix A / Geometric Points
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14.4 NAVSTAR GPS Reference Points
The set of 24 reference points {ni} of the satellites comprising the
NAVSTAR GPS constellation.
14.5 Missile Centre of Gravity
Point (c) is the missile centre-of-gravity in a locally uniform gravitational
field that lies on its longitudinal axis of rotation. During the boost phase
this point moves along the longitudinal axis as fuel is expended. When the
missile is treated as a point mass points (c), (u) and (m) are coincident.
14.6 Missile IMU Reference Point
Point (u) is the IMU reference point on the missile’s longitudinal axis.
14.7 Missile GPS Receiver Reference Point
Point (g) is the NAVSTAR GPS reference point that lies on the upper
surface of the vehicle in the longitudinal plane spanned by X B and Z B .
14.8 Seeker (Missile) Reference Point
Point (m) is the seeker gimbals centre of rotation that lies on the missile
longitudinal axis. This point also acts as the electronic centre for the
detector and is also the missile’s reference point. When the missile is
treated as a point mass points (c), (u) and (m) are coincident.
14.9 Missile Geodetic Position
Point (d) is the intersection of a geodetic vertical through point (m) and the
WGS-84 geoid.
14.10 Missile Ground Position
Point (f) is the intersection of a geodetic vertical through point (m) and the
ground represented by 3 rd order DTED interpolation centred about point (d).
14.11 Target Reference Point
Point (t) is the target reference point when it is treated as a point mass. It is
also used as the observation point for the radar and seeker models in the
absence of measurement glint.
14.12 Target Impact Point
Point (b) is the point at which the missile and target collide.
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