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

Appendix I / Utilities / WGS 84, Target and Missile Data
_ _
22.3 WGS 84, Target and Missile Data
The simulation utilises many target and missile dynamic parameters that are
derived from the reference state vector. Although these parameters can be
derived in-situ as a need arises, their computation is centralised so that they
are easier control and modify. The modules involved in this process are not
strictly utilities since they have been developed for a specific purpose.
However, they demonstrate how the utilities are combined to generate the
kinematic parameters required.
2
TARGET SIGHTLINE
DATA WRT
LAUNCHER/GROUND
BASED TRACKER
EARTH REFERENCED
TARGET AND
MISSILE DATA
22.3-1
UPDATE
KINEMATIC
DATA
1
4
TARGET & MISSILE
SIGHTLINE
KINEMATICS 4
5
MISSILE TO TARGET
SIGHTLINE
KINEMATICS
3
MISSILE SIGHTLINE
DATA WRT
LAUNCHER/GROUND
BASED TRACKER
Figure 22-5 : Kinematic Data Precedence
The kinematic generator modules must be executed in the hierarchical order
indicated by numbered arrows in Figure 22-5. Each module has two
separate forms, one based on reference state data, the other on observer state
vector. All parameters are derived, from reference data at 4 kHz the state
integration rate, and from observer data at 400 Hz. This is simpler than
implementing multi-rate logic.
22.3.1 Missile Closest Approach Detection and Reporting
C_APPROACH monitors the LAUNCH flag at the state integration rate.
After missile launch, range-to-go is interrogated and the STOP_MONITOR
activated to test the following program termination conditions:
• Missile speed < 200 m/s
• Closing speed < 200 m/s
• Range-to-go < 1000 m and Seeker LOS angular rate > 10,000°/s