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Gear animations - center of rotation

Postby legoboyvdlp » Mon Jun 08, 2020 10:39 am

This may be somewhat obvious but the compression animation is breaking the tyre spin animation. I defined the axis and center for the latter- but when the gear compresses and extends, then the tyre keeps spinning around that center.

Is there some way to ensure that the center of rotation moves with the translation animation?
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Re: Gear animations - center of rotation  

Postby WoodSTokk » Mon Jun 08, 2020 11:05 am

I think it is the order of animations inside the xml file.
On the Citation II it works as expected.
First animation is the rotation of the gear assembly.
Second animation is the translation of the damper (with fork and wheel).
Last animation is the spin of the wheel.
There are some locked-track animations for the actuator, scissors and doors.
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Re: Gear animations - center of rotation

Postby legoboyvdlp » Mon Jun 08, 2020 11:24 am

Ok, thank you :)

Inverting the order of the animations does seem to have fixed it +1
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Re: Gear animations - center of rotation

Postby legoboyvdlp » Sat Jun 20, 2020 5:49 pm

Thanks - the locked track was very useful!


Is there any soloution to animate something using locked-track in 3D -- I set up an animation for the strut which has two parts, with one parented to the other.

Image

However, the result is twisted as you can see (ignoring all the other components, only the biggest one).

Image

It looks right -- but if you actually look into the bay you can see that the result is twisted.

Obviously, I know you can specify the lock-axis and track-axis using a vector of <x>, <y>, <z>. I set it up getting coordinates / axis from Blender... it should have worked, and indeed it does work.

It seems the two parts (which are parented to eachother properly) are not animated in the plane of the lock-axis / track-axis!
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Re: Gear animations - center of rotation

Postby WoodSTokk » Sat Jun 20, 2020 8:46 pm

Looks like a gear from a airliner with many moving parts.
Can i download the latest blender and xml file for a closer look?
Out of that image i cant see what part should move in which direction.

EDIT:
I think you mean this little hydraulic actuator that push the down-lock if the gear are extended.
But, hmm, this two parts (cylinder and piston) are normaly moving on one plane (AFAIK), so the lock-axis should be the face-normal on that plane.
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Re: Gear animations - center of rotation

Postby legoboyvdlp » Sat Jun 20, 2020 11:26 pm

Not quite -- I mean the large strut to the left which is in a v-shape pointing to the right. Of course the rest needs animated but I want to get the main bit working!

I am unable to provide blender atm, as this has local changes that I can't push (I parented objects properly on my side for testing purposes) -- once CaptB pushes the new .ac from his end { we have a strict policy that the model is off-limits in git :) } then would be glad to.

https://media.discordapp.net/attachment ... nknown.png

So - in this image, it is the most visible strut, running from center of gear down and to the right. It should fold as the gear retracts:

Image

I have this animation implemented - but as seen in this succession of images it gets more or less twisted. It is hard to show on screenshots:

Image

Image

Image

I took lock axis as perpendicular to the strut -- that is:
Image

I hope you can understand this -- sorry if I can't explain it properly but it is my first time with this animation :)
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Re: Gear animations - center of rotation

Postby WoodSTokk » Sun Jun 21, 2020 2:39 am

For me, it looks like this strut does not only fold, it will also rotate.
So you need two locked-track animations, one for rotate and a second for (un)folding.
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