Figure 6-15.-FLIR positioning/stabilization block diagram.
The LOS of the receiver is selected in one of three
ways:
. By a program in the aircraft’s computer (or a
video tracking computer when the system is used with
a laser system)
. By inputs from the target tracking sight control
. By operator adjustment of the azimuth and
elevation controls on the control box
The control servomechanism WRA processes
these azimuth and elevation commands, no matter
from which source they come. This WRA will then
apply drive signals to the receiver head positioning
motors and gimbals. The receiving head is aligned
to the desired LOS. If the aircraft should pitch or
roll, the gyros (mounted on the receiver head)
initiate error signals to a capture loop. This loop
creates azimuth and elevation rate signals. The rate
signals are fed back to the control servomechanism
(CS). The CS will then process these rate signals
and apply them to the receiver head as drive signals
to maintain the correct LOS. In the manual mode
(which uses the target tracking sight control), the
stabilization system is inhibited in the control
servomechanism assembly.
BITE System
Most FLIR systems are equipped with a built-in
test equipment (BITE) system. The receiver-
converter BITE subsystem monitors status signals
from the following subassemblies:
Camera video
Refrigerator unit
Gimbals from the control servomechanism
assembly
Scan mirror and TV camera scan
Focus drive of the lenses
Heat exchanger
6-13
