Docked at the ISS for the first time!

Thorsten

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It took me a couple hours yesterday, but I managed to dock to the ISS for the first time!

Congratulations - seems you are persistent!

I guess it gets easier once one has the basic idea down.

Also, in reality there's some help available. I remember taking an hour or so to dock Orbiter's stock Atlantis to ISS for the first time. My main problem was that the docking collar is 'upwards' and 'behind' the cockpit. so when you see it looking up, the control inputs are all wrong - to roll around your view axis you have to yaw the Shuttle for instance - which I got wrong about a dozen times - and periodically I had to adjust attitude because 'kill rotation' stabilizes the Shuttle attitude inertially, but ISS has fixed attitude in the LVLH (local horizon) frame.

Well, turns out the real Shuttle has not only an LVLH-attitude hold mode but also a switch to change the sense of the controls to what you see looking up - that makes the problem much more tractable.
 

Arvil

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@Thorsten. Yeah, it makes just feel all wrong, and the arm isn’t real friendly. But, seems to me some one put up in Orbiter Hanger a mod that translates the RCS for docking, and the arm so that you drive the ‘hand’ and the system drives the elbow and shoulder.
 

Thorsten

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But, seems to me some one put up in Orbiter Hanger a mod that translates the RCS for docking, and the arm so that you drive the ‘hand’ and the system drives the elbow and shoulder.

Well, fast-forward my experience by a couple of years, and writing an autopilot which just docks any spacecraft for me becomes a trivial exercise:)

(Actually, automated flight in space isn't that hard, it's a very quiet and predictable environment - designing an AP that can hover and land a helicopter in gusty winds... now that was a real challenge...)

So the question for me really is - what skills would a real astronaut require? Docking with the original Shuttle avionics is a challenge I consider still meaningful.
 

N_Molson

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what skills would a real astronaut require?

A very "stable" psychologic profile, the ability to deal with information overflow. I've seen seemingly very rational people doing pure nonsense when they were under high stress (like beaching a sailboat straight on a very visible sandbank, after 3 repeated warnings...). The ability to put aside personal feelings so that it won't interfere when the crewmate you don't like asks you to do a specific task. Of course good reflexes and coordination, and excellent spatial orientation (very useful when you're docking a spacecraft with an offset docking port like the Shuttle, and also for limiting the "falling into Earth" feeling/disorientation on EVAs). Well inner ear is something that can be trained, but probably some people are better than others. Also you have to understand how work the systems you're working with, and in the case of the Space Shuttle (1M spare parts...), it was no small feat. So most astronauts are highly specialized (PhD) in space-systems engineering, some have double-specialization for mission specialists skills (like biology, psychology, medicine...). Which means those are people that learn fast and well.
 

Thorsten

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I've seen seemingly very rational people doing pure nonsense when they were under high stress

Well, simulators are excellent ways to test yourself in that respect if they have decent immersion. I've acquired a good understanding of many GA aircraft crashes that way.

I used to do a lot of simulated mountain flying with a single prop plane. So sometimes the weather deteriorates, and I find myself thinking 'Hey, I can do that, I know the area really well, I just push above the layer, visuals will be gone for no more than a few minutes, no problem' And then finding myself in a narrow valley with no space to turn, headed for a rock wall.

There are also the frequent conversations with users that go like 'The AP killed me - it just pushed into a steep dive!' - 'Why didn't you disengage it?' - 'I though it knew what it was doing!?' - 'When pushing you into a steep dive?'

Rationality is sometimes in your way because you're wasting time analyzing which you should have used acting.

So I know I'm not really up to high stress level astronaut decisionmaking - the more standard failures in the Shuttle like single engine failures I can handle, but complicated ones I tend to fail.:confused:
 

IDNeon

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Well, turns out the real Shuttle has not only an LVLH-attitude hold mode but also a switch to change the sense of the controls to what you see looking up - that makes the problem much more tractable.

How do you handle the LVLH problem without the convenience of those tools?
 

IDNeon

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A very "stable" psychologic profile, the ability to deal with information overflow. I've seen seemingly very rational people doing pure nonsense when they were under high stress (like beaching a sailboat straight on a very visible sandbank, after 3 repeated warnings...). The ability to put aside personal feelings so that it won't interfere when the crewmate you don't like asks you to do a specific task. Of course good reflexes and coordination, and excellent spatial orientation (very useful when you're docking a spacecraft with an offset docking port like the Shuttle, and also for limiting the "falling into Earth" feeling/disorientation on EVAs). Well inner ear is something that can be trained, but probably some people are better than others. Also you have to understand how work the systems you're working with, and in the case of the Space Shuttle (1M spare parts...), it was no small feat. So most astronauts are highly specialized (PhD) in space-systems engineering, some have double-specialization for mission specialists skills (like biology, psychology, medicine...). Which means those are people that learn fast and well.

Very awesome and succinct. But now how do you demonstrate that and get hired? Especially these days. Seems space flight is rarer than visiting the Titanic...again.
 

Thorsten

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How do you handle the LVLH problem without the convenience of those tools?

Without any claim to this being a real procedure:

Patience and discipline - the LVLH frame rotates fairly slowly. Ideally you align one axis with it so you only need to correct that axis. While you do your translation maneuvers, you remember to switch to rotation every two minutes or so and quickly correct attitude, then you switch back. You just have to remind youself to do the attitude corrections, it's unfortunately easy to forget. And you absolutely have to remember which axis to rotate, if you pick the wrong axis it all becomes a mess...:cool:
 
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