IRS

Question 1

SAGNAC EFFECT

Answer 1

~light takes longer to complete the journey if the path is rotating in the same direction as light is travelling
~it takes less time for the ight to complete the loop if the path is rotating in the direcion opposite to that light

Question 2

Interference patterns

Answer 2

~when two occupacy the same space their effects are added toghether
-wave peak plus wave peak makes an even greater wave peak
- wave trhough plus wave trough makes an even greater wave trhough
-wave peak plus wave through equals zero (they cancel each other out)

Question 3

Interference pattern

Answer 3

~two light beams in similar frequemce willcreate an interfernce

-interferefcne patterns creatd by light produce light and dark lines
-this pattern is very sesitivy to the slightes change in the frequency of the beams

~pattern is projected onto a light detecor

Question 4

RLG errors

Answer 4

~suffer from random drift
~accuracy improved by increasing the path length

Answer 5

~speed proportianl to the rate of rotaion of rRLG
~detector output is used to calclate the rate of rotation
~RLG no gyros
~~powrr up 1sec
~rlg suffer from drift

Question 6

Laser lock

Answer 6

When there is small movement
The error is solved by PIEZOELCTRIC MOTOR ,vibrating

Answer 7

Airdata modules use solid state pressure transducer

Question 8

ADIRS FAILURE

Answer 8

If the sys fails ,its still able to operate in standalone mode provinding lat and long read out on a detected display

Adirs sys comprises 3 adiru

Question 9

Strap down

Answer 9

3 rate sensors
3 accel

Question 10

Skewed axis sensors

Answer 10

Computing power
~6 acclerometer and 6 rate gryos are set on 6 axes ,nono of which align with x,y,z axes of the a/c
~from the a/c orignal attitude the irs uses the rate gyros to keep track of tis attitude
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