Talk:Space rendezvous

Latest comment: 1 year ago by 137.188.108.202 in topic Docking

Docking

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It would be great to have some more information/article(s) on docking and docking devices such as docking rings. Suprisingly any relevant information on these seems to be very rare. Jiri Svoboda 17:52, 4 November 2007 (UTC)Reply

Shouldn't be too difficult to find the info online on the Gemini and Apollo docking mechanisms, for the historical aspect. 137.188.108.202 (talk) 14:57, 19 June 2023 (UTC)Reply

Docking vs. Berthing

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I have heard of a technical distinction between docking and berthing. In this usage,

  • docking is the "controlled crash" of two vehicle masses into one another via standard spacecraft reaction control (flight dynamics) such that a mechanical docking mechanism of some sort is engaged, and subsequent airlock etc. can be established. In contrast,
  • berthing is the movement of two spacecraft into the same orbit, with only a few meters of separation, and very precise station-keeping. Once in these relative positions, an electronically-controlled mechanical arm (like Canadarm or Dextre) are used to make a mechanical connection between the two vehicles, and then the mechanical arm is used via electric control to bring the two craft into a stiffer mechanical connection, and for some vehicles (e.g. H-II Transfer Vehicle into a subsequent airlock connection.

Two questions. Is such a distinction made in standard space literature? Does anyone know of a good source for this distinction? I don't see the distinction made in the article today but think it may be a quite useful addition given that both of these variants are widely practiced in space today. Cheers. N2e (talk) 19:33, 2 January 2011 (UTC)Reply

Here is a source[1] that describes the Berthing process for the Japanese HTV with the ISS. Might be a useful illustration of berthing for the article if we can find a verifiable mainline source that makes the berthing/docking distinction. N2e (talk) 20:02, 2 January 2011 (UTC)Reply

References

  1. ^ JAXA (2007). "HTV Operations". Retrieved 2011-01-02.

China completes first space docking: November 2011

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A first for China, a successful docking of two unmanned spacecraft:

"Successful docking of Chinese spacecraft

Shenzhou 8 and Tiangong 1 successfully hook up in space: /-- China Succeeds in First Space Docking by 2 Spaceships | - Space.com

/-- China completes first space docking test - Reuters"

Cheers, N2e (talk) 06:06, 3 November 2011 (UTC)Reply

Disputed Gemini 8 addition

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This text recently inserted by an IP needs to be removed from here, not because it is uncited, but because it is out of scope in this article:

Shortly after docking, one of 16 Gemini spacecraft thrusters experienced an electric short, sending the spacecraft into a 1 RPS spin. Neil Armstrong & Dave Scott came very close to blacking out and being the first crew to die in space. It took more than 30min to get the Gemini 8 spacecraft under control by isolating which thruster was misfiring, as a result most of the fuel was used up for the primary system and much of the fuel for the re-entry thrusters was consumed trying to stabilize the spacecraft. The mission was cut short, but still accomplished it's primary goal of the 1st docking in space and the spacewalk by Dave Scott cancelled.

This article is about the subject of rendezvous and docking. Docking was successfully achieved, and what happened afterwards is irrelevant to this article. There is a hyperlink to the Gemini 8 mission, which is where this kind of detail belongs. You're welcome to merge it in there.

Also notice, the Citation needed tag was not put in the place intended; it's by a reference to Gemini 6. JustinTime55 (talk) 15:58, 2 August 2012 (UTC)Reply

Soyuz & Progress launch & rendezvous with ISS in 6 hours

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You got to explain how they were able to rendezvous and dock the progress transports and Soyuz in only 6 hours. There must be some major differences to the traditional way to do it. — Preceding unsigned comment added by 194.237.142.21 (talk) 07:59, 2 April 2013 (UTC)Reply

First of all, the Russians make use of the latitude of their launch site. The latitude of the Baikonur Cosmodrome is 46°N, only 6° less than the orbital inclination of the ISS. Therefore, the cosmodrome moves only slowly through the orbital plane of the ISS, giving a long launch window in which a spacecraft can be launched into the ISS's orbital plane. This allows them to choose the launch time such that the spacecraft is not only in the right orbital plane, but also close to the right orbital phase. Put simply, the Russians launch the Soyuz or Progress just minutes after the ISS moves through the zenith over the cosmodrome, which because of their latitude happens more or less every day. They can skip what is called in the article Drift Orbit A and reduce Drift Orbit B to just two revolutions followed a bi-elliptic transfer.
Then, proximity operations are also accelerated. The final 600m until capture take only 20 minutes (see one of those videos of a Soyuz docking). Must have to do something with their automatic docking system. See also this video produced by ESA: [[1]].
PiusImpavidus (talk) 14:07, 17 April 2015 (UTC)Reply
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The second reference (Earth to Moon to Earth - Buzz Aldrin) is 404... (Cesarakg (talk) 01:55, 15 August 2014 (UTC))Reply

R-bar Approach

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Current text:

When below the target the chaser fires radial thrusters to close in on the target. By this it increases its altitude. However, the orbital velocity of the chaser remains unchanged (thruster firings in the radial direction have no effect on the orbital velocity). Now in a slightly higher position, but with an orbital velocity that does not correspond to the local circular velocity, the chaser slightly falls behind the target.

Analysis:

Chaser is below the target, and therefore has higher orbital velocity than target. Chaser thrusts radially to increase orbital radius. Orbital velocity is unchanged. Chaser now has orbital velocity greater than local circular velocity, and so pulls ahead of target, not behind.

Suggested text:

When below the target the chaser fires radial thrusters to increase its altitude. However, the orbital velocity of the chaser remains unchanged (thruster firings in the radial direction have no effect on the orbital velocity). Now in a slightly higher position, the chaser's orbital velocity is greater than the local circular velocity, and so the chaser slightly pulls ahead of the target. — Preceding unsigned comment added by 2604:2D80:C805:81AA:5CC2:5F51:59B5:F34C (talk) 02:42, 30 August 2018 (UTC)Reply

I agree. This is currently misleading. However, this would then need some additional work, as the maneuver described would not lead to a successful docking. Are there any good sources for that maneuver? 147.86.175.51 (talk) 08:13, 13 May 2023 (UTC)Reply

Requesting more discussion of relative navigation in V-bar and R-bar coordinates

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Ladies and Gentlemen, 2601:151:C304:7200:E192:E5E:2D5E:E8AE (talk) 09:22, 27 July 2022 (UTC)Reply

Article is mostly about manually controlled rendevous - Could have a section on automated rendezvous

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Article is mostly about manually controlled rendevous - Could have a section on automated rendezvous and proximity operations, which could mention DART (satellite) (failed) and Orbital Express (needed manual intervention). - Rod57 (talk) 18:25, 30 July 2022 (UTC)Reply

Is the science described here correct?

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" A spacecraft in a certain orbit cannot arbitrarily alter its velocity. " What? I'm no scientist, but this article then goes on to explain that a spacecraft CAN alter its velocity. Maybe someone with good understanding and writing can update it. 137.188.108.202 (talk) 14:54, 19 June 2023 (UTC)Reply