Gyroscopic space robot avoids negative reactions

Thanks for the comments, got done reading them and understand it more now.

However, why is it that you can't use a conventional motor in space? the inertia created by it when it spins or what?

Baring in mind that I have taken note that there are other advantages to using gyroscopes for this application - I have to ask, if they're not using motors (which don't work well in space) to power the arms then what are they using to power the gyroscopes hmmmm?

And I agree with the people who ask "why haven't they done this before?" hehe, it's remarkable how clear forward vision is in hind sight.

If I understand it correctly, the re-active force from pushing a satellite with the arm is countered by the gyroscopes instead of the shuttle, so they don't have to use fuel to keep shuttle on course.

LukeSkyscraper; The gyroscopes do use motors but they work in pairs.

Imagine you were floating in space with your arm by your side. If you extended your arm using your shoulder muscles (motor) your body would move in an equal and opposite manner.

(Continued...)

...If, however, you extended your arm using paired gyroscopes attached to your wrist, your body would not move (as much).

I'm guessing that the orientation/speed of these gyros requires considerable effort to control in order to minimize 'body' movement, and isn't at all as straightforward as some people believe. ;-J

I understand the principles of how it works :) I was just being unnecessarily pedantic about the statement that it doesn't use motors :). After all the gyro's don't spin themselves. So it does use motor's just indirectly and I understand that the arm isn't actually necessary either. You could use the gyro's to move a free floating object, the arm in this case is as much of a tether and communications link as a guide. The reactive forces on the spacecraft body will be far less than usual.

Hmmm... Not quite pedantic enough. A true pedagogue would never have misinterpeted their own abbreviation of the stated phrase, 'conventional motor' ;-J

Also, you could use the gyros to move a free floating object, but only a rigid (when neccessary) arm can hold an object in perfect relative position to a spacecraft, allowing the spacecraft to perform manoeuvres without slewing away from the object.