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Talk:Gimbal lock

Latest comment: 4 months ago by 2603:8080:2B00:11D4:A7E1:B184:5B55:6999 in topic History?

Confusing sentence

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"If the aircraft pitches up 90 degrees, the aircraft and platform's yaw axis gimbal becomes parallel to the roll axis gimbal, and changes about yaw can no longer be compensated for."

Why? — Preceding unsigned comment added by 2601:58B:4280:1180:A145:89C9:C8A2:9234 (talk) 22:32, 10 November 2021 (UTC)Reply

Math formula rendering is broken

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Attention to Authors and Mediawiki team/admins: There is a Math markup related error in this page. It is displaying the following message "Failed to parse (Cannot write to or create math output directory)" — Preceding unsigned comment added by 83.139.17.163 (talk) 14:05, 7 September 2012 (UTC)Reply

Page rewritten

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Things that got better:

  • I have rewritten the introduction to make it "good introductory style" as requested (or at least, I hope that).
  • I have separated the approaches "gimbal lock in vehicles" (gyroscopes, submarines, aircrafts and spaceships) from "gimbal lock in maths" (explaining the problem with euler coordinates, and quaternion alternative).
  • I have made an illustration for the "mechanics" part.
  • I have removed the final paragraph about singularities on a map of the sphere, and south pole on the Earth. That was way too allusive and almost unrelated to main focus of this article.
  • I have taken into account the remarks on this discussion page
  • I have "stolen" some material from Inertial measurement unit and from gimbal

Things that still need improvement:

  • The "mechanics" section probably needs some more work, as my speciality is maths and not mechanical engineering.
  • Also, English is not my mother language, so the article is probably full of strange phrasings and language mistakes.
  • I have added myself a "needs more citations" template. Most of the material is taken either from my mathematical knowledge, my experience with 3D graphics, or other Wikipedia articles. That is unfortunately not "independant sources", even though I think the article is already much better than before I started.

Thanks in advance for correcting me. MathsPoetry (talk) 06:50, 1 February 2009 (UTC)Reply

Moon or moon?

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Should we use initial caps on the word Moon? Is Moon the proper name for our moon, or is it just a generic term identifying the kind of heavenly body nearest Earth? In other words, is Moon to our moon as Earth is to our planet? Or is it part of the proper name for the Apollo Moon mission? John (talk) 21:54, 9 February 2009 (UTC)Reply

Wikipedia article Moon clearly capitalizes "the Moon" when it is our moon, so I think the rule is the one you describe above.
MathsPoetry (talk) 09:20, 10 February 2009 (UTC)Reply
Good point, MathsPoetry which raises the question "Are they right?" I don't really know. So I asked at Moon. John (talk) 00:52, 12 February 2009 (UTC)Reply
I imagine it just depends whether you're using 'the Moon', or 'a moon'. LieAfterLie (talk) 07:11, 13 August 2011 (UTC)Reply

The maths is wrong

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When choosing the axes of rotation, one must choose different axes. The proof written here is transforming a vector x by a rotation in Z-X-Z. However due to the commutative properties of matrices (i.e. ABx=BAx), ZXZx=XZx, Which of course when setting X to an identity matrix will only have one axis of roatation. A proper Euler 'set' needs an X Y and Z rotation. — Preceding unsigned comment added by 2.222.106.85 (talk) 23:15, 30 May 2012 (UTC)Reply

Yes, there needs to be a y axis rotation, otherwise your example is trivially satisfied. — Preceding unsigned comment added by 109.154.80.111 (talk) 15:12, 30 October 2012 (UTC)Reply
Agree. If anyone here understands the problem well enough for an encyclopedia, please fix the math. --Dlazerka (talk) 02:37, 24 November 2014 (UTC)Reply
Since no one attempted to correct the maths example for two years I'll attempt it - might not be perfect, but won't be worse, since the current example is completely invalid. Mikoszrrr (talk) 22:11, 25 December 2014 (UTC)Reply

the math renderer thing seems to be borked

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the article is sprinkled with a lot of errors from the thing that processes the math formulas or somthing --TiagoTiago (talk) 03:52, 22 May 2009 (UTC)Reply

I think that you mean that the conversion from TeX formulas to images is not okay. I don't see any problems with it. Could you be more precise and give examples of such problems? Thanks in advance. MathsPoetry (talk) 08:29, 22 May 2009 (UTC)Reply

Yaw and roll confused in the 3D example

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I was so confused out of my mind that I had to construct a crude gimbal from cardboard and toothpicks. When the innermost (red) ring rotates on an axis perpendicular to its plane, this uses the bearings between the outer two rings, and the plane pitches. Pitching directly upwards puts the two outer rings in parallel. However, in that condition it is still possible to yaw by twisting the innermost ring on the bearings between it and the middle ring, as usual. The outermost (blue) ring no longer corresponds to the plane perpendicular to the yaw axis - and none of the rings do - but yawing is still possible. What can't be done is rolling, which puts a shear force on all the bearings. - Kevin 99.244.184.166 (talk) 06:42, 22 March 2010 (UTC)Reply

The drawings to the right of the "gimbal lock in 3D" are wrong for the aircraft example. In aeronautics we have a "yaw-pitch-roll" convention. I.e. the airplane should be fixed to the inner (blue) ring, next comes the red ring, and the green ring is the outer ring. The upper drawing could be corrected by whoever made it, by showing the aircraft from the rear, i.e. flying away from the viewer, with otherwise unchanged rings. Then the second drawing should show the aircraft pitched up by 90 deg., so that you look at its top. Then the blue ring and the green ring are parallel, with the red ring inbetween. It then is clear, that the same aircraft position can be achieved with an infinite number of inner and outer ring positions.

Even better would be if those two drawing would have the same color for the rings as the animation at the top of the wiki article. I.e. the inner ring red, the middle ring green, and the outer ring gold or yellow. [Joe]

Actually this 3D example doesn't make any sense to me at all. The example seems to imply the plane itself is subject to gimbal lock which is certainly incorrect. A plane moving vertically can still yaw, with the rotation around the vertical axis of the airplane, which is not necessarily aligned with the vertical axis of the Earth. What can gimbal lock is an instrument or device mounted in the airplane, but in this case the mounts for the gimbal should be fixed relative to the airplane's vertical axis, not the Earth's vertical axis as shown in the figure. [Jeff]. — Preceding unsigned comment added by 128.237.224.17 (talk) 14:45, 5 January 2012 (UTC)Reply

Opening line

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"Gimbal lock is the loss of one degree of freedom in a three-dimensional space that occurs when the axes of two of the three gimbals are driven into a parallel configuration, "locking" the system into rotation in a degenerate two-dimensional space."

I haven't read the article, but briefly looking at the first sentence and from what I think I understand of gimbal lock... you don't need two of the three axes to be parallel to each other. You only need all three axes to be in the same plane. In most gimbals the axes are all at right angles to each other, so the only way for them to be in the same plane is for two of them to be parallel. But the given description implies that you can just prevent gimbal lock by not using right angle axes. LieAfterLie (talk) 07:05, 13 August 2011 (UTC)Reply

Conversion of quaternion into mechanical model?

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Since quaternions are able to completely avoid the problems of gimbal lock, it possible to convert the math of a quaternion into a direct physical model?

Or is this not possible because the quat assumes a 4th degree of motion is available that doesn't exist in 3D space?

-- DMahalko (talk) 22:05, 19 December 2012 (UTC)Reply

The mere use of quaternions does not solve gimbal lock.

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The Quaternion Solution section talks about how quaternions solve gimbal lock. They don't. Gimbal lock is the result of using 3 angles to represent an orientation. The solution to gimbal lock is to not represent an orientation as 3 angles; you represent an orientation as an orientation, a single unit value.

There are two ways to represent an orientation as a "value": matrices and quaternions. The problem with matrices comes from applying successive transformations; the matrix stops being ortho-normal after a while. So you have to re-orthonormalize it, which is a complex process. Orthonormalizing a quaternion is just a simple normalization operation.

So quaternions do not magically solve gimbal lock. They're simply a good alternative representation of an orientation instead of 3 angles. Korval (talk) 01:58, 16 March 2013 (UTC)Reply

Oh yes it does! There are several ways of representing three dimensional rotations. The problems you mention are an artifact of limited precision, which causes error in all representations. Quaternions magically solve gimbal lock. I have removed the disputed section template. PatheticCopyEditor (talk) 18:12, 10 April 2013 (UTC)Reply
The link you posted is simply talking about the ways to represent an orientation. It doesn't answer my point. I came here and put that tag there because of a question on Stack Overflow that explicitly linked to this Wiki section. The person used quaternions, but they didn't magically solve his gimbal lock. Why? Because he was simply converting the Euler angles into three quaternions and multiplying them together to get the actual orientation. *That* is the point I was trying to make, that "using quaternions" isn't good enough if you still represent the orientation as 3 axial rotations. You have to stop representation the orientation as 3 angles. Korval (talk) 02:26, 12 April 2013 (UTC)Reply
In short, the solution has nothing to do with quaternions specifically. The solution is to find an alternative way of representing an orientation. Korval (talk) 02:27, 12 April 2013 (UTC)Reply

Animated Gif

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Is there any way to convert animated gif's so that they stop their animation. It is impossible for me to concentrate on the text, and maybe I am a little slow, but it does not do much for me to clarify the subject also. It would be a cool feature to turn the animations of by clicking somewehere on the gif.82.171.79.72 (talk) 01:08, 11 July 2013 (UTC)Reply

Agree! Alternatively slow down quickly the animations go through frames - currently the one at the top of the article and to the right rotates too fast to see anything meaningful! — Preceding unsigned comment added by Bhav Khatri (talkcontribs) 12:52, 12 January 2019 (UTC)Reply

"Lock" is not misleading.

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If a gyroscope is gimbal-locked, then it can be forced to rotate via its housing; it is effectively locked to the housing. 70.79.163.252 (talk) 15:32, 19 June 2017 (UTC)Reply

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Animation

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Why can't the green ring continue rotating? — Preceding unsigned comment added by 2601:589:8101:8D30:A42B:402C:948F:2B0E (talk) 13:29, 16 October 2021 (UTC)Reply

The animation is way too fast, and the lack of annotation makes it pretty useless in helping a layman to grasp the concept. The caption doesn't help much. WP Ludicer (talk) 07:41, 15 August 2022 (UTC)Reply

History?

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I hope Wikipedia one day has History section on even a topic as obscure as this. Who discovered Gimbal Lock? Who developed resolutions to it over time? 2603:8080:2B00:11D4:A7E1:B184:5B55:6999 (talk) 20:44, 14 July 2024 (UTC)Reply