Animate rotation around local axis

[Hueyman]

Hi guys,

I’m sorry I know this has been covered numerous times but I never succeed to understand nor make ti work properly every time, could please someone explain me with steps on how to do it ?

I’m looking for a simple propeller motion blur in cycle using rotation keyframes and animating it around it’s local axis of rotation ( the plane being in different orientation than global axis ).

I can make it rotate as I want with Transform Orientation and local axis ( R - X - X for example , or with the widget ) but when I play the Animation it spins around weird axis ( but start and ends at the correct location ).

I would need your help friends !

Cheers,
Hueyman

[Modron]

try putting an empty at the center of the prop, then parent the prop to the empty, then use numerical input on the empty to rotate it.

[Emil_Assarsson]

Did you parent the prop to the plane? It might be easier to see whats going wrong if you post the blend file.

[Hueyman]

@Modron :

Used this technique ( but with a bone ) and same result, looks like Blender doesn’t allow animation around local axis ( which sounds weird ) but many people seems to have the same issue and the solution was workarounds I didn’t really understood …

@Emil :

Sorry this is a big project I don’t want it to publish it on the net

Thanks for your input guys

[Photox]

This will work:

1. ensure that all rotations are applied on everything.
2. Create an armature, a single bone really, along the axis of prop rotation.
3. Parent the bone, in object mode, to the main airplane.
4. parent the prop to the bone, (choose bone)

5. Select the bone, and switch to xyz euler mode.
6. frame 1 - create a keyframe for loc/rot on the bone (in pose mode)
7. next frame say 120, in pose mode, R Y Y, and insert keyframe los/rot

now you can keyframe the airplane, in object mdoe doing anything the prop will respect the local axis (for armatures the local Y axis runs with the bone, you would think it might be z but it’s not)

Parentage

Airplane
Bone
Prop

[Hueyman]

Hi,

Thanks Photox, but for some reasons, that didn’t work.

I’m 2mm from throwing everything thru the window, really … lol

Here is a little prop sample so maybe you could actually show me how you would animate that, in the current prop orientation, with simple loc/rot keyframes…

http://pasteall.org/blend/index.php?id=43335

Thank you very much

[Photox]

You have issues with the object will will prevent you from moving forward. first you have unapplied rotations,location, and scales. You can get rid of those by alt g , then alt r, then ctl a , choose scale.

What much worse is that you have rotated the mesh in edit mode such that it no longer aligns with any axis.

Come back and post a prop with no rotation, location, or scale issues properly align to an axis and I can help you.

It is possible to add a bone, that is aligned with you prop and use the local rotation, but it’s going to be a mess, and you should start organzing and getting better at the fundmanetals.

Always model on on an axus, and then uif you need to rotate, roatte in object mode, or add an armature and rotate in pose mode.

Keep at it.

[Hueyman]

Hi,

Sorry, I don’t get what you say…

Here is an updated .blend with correct applied scale and local axis, rotated in object mode not edit one, but what is the difference ?

Could you please show me on this .blend how you would do that ?

I understand I may miss the fundamentals, but I modeled a whole airplane without any problems and it’s the first time I got stuck like this for such a basic task.

Thanks a lot,
Hueyman

[Photox]

No link to new blend…

[Hueyman]

http://pasteall.org/blend/index.php?id=43371

[Photox]

Here is a 3 minute video of your prop rotating in local space using a bone, parented to a main airplane.

direct link

[Hueyman]

WOW thank you very much Photox for your time and patience, it paid off

[Photox]

I’m glad you got it working, the first time can be frustrating, but remember the second time is 10 times easier.