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Garth
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#14
Feb21-06, 04:52 PM
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Quote Quote by RandallB
In space how do you define up down left right forward and back with no references.
Same thing here, I don’t see a defined reference.
From the plane of the satellite's orbit (N-S) and the orientation of the Earth(E-W).
For the gyro that is pointed at the guide star.
Option 1:
The axis end pointed at the star tips up to the North the back end will of course tip down to the south.
Option 2:
The opposite happens, the end axis pointed at the star tips down to the South the back end will of course tip up to the North.

Which option is the N-S move Option 1 or 2?
We can assume N-S means “from North towards the South” movement.
But without defining which end of the gyro is being measured how does any one know what the other is talking about.

Same kind of problem understanding the other gyro measements in 3D.
The Spin vector of the gyro is defined by the Right Hand Screw convention, so long as that convention (or the opposite one) is applied consistently in the analysis there is no ambiguity.

Garth