Set bone rotation?

Hi all,

First of all, thank you Epic for this suprise! A nice Spring 1st day!

I have a question about skeletalmeshes. Is it possible to set a particular bone’s rotation and location by using blueprint? I m trying to implement a genetic algortihm based procedural animation system. So the first step is a precise manipulation of the skeleton. :wink:

Thanks to all.

It’s very easy to do this in an Animation Blueprint using the Skeletal Control “Transform (Modify) Bone”. More info here: Skeletal Controls | Unreal Engine Documentation

Ok, thank you Arnett! I will read that this evening.

I hope there is no stupid question…

I have tried to update the rotation value (BMM_additive) of a bone from the HeroTPP skeletonmesh at each frame. But the bone moves only once when I simulate or play the animation in the Animation Blueprint previewer.

Could somebody tell me how to ask to the engine to rotate a bone by a precise angle in a precise time interval? Or on a frame basis?

Thanks a lot!

Not a stupid question at all.

Your current setup is applying a single 60 degree rotation on top of the animation pose. If you wanted to make that rotation dynamic, you could connect a variable to the Rotation input and then modify that variable in the Event Graph.

I actually just used a similar setup for a robot character with rocket boosters that played a hover animation. Whenever the character turned, I would take the amount it turned and rotate the rocket boosters (to look like they were driving the turn) using a Transform Bone node.

I made a quick test to illustrate how this works. The two images show the Anim Graph with the rotator variable and the Event Graph where that variable is being set to a random value.

I believe he actually meant how to change rotation during time interval. ****, use Lerp (Rotator) to achieve that.
I have another question about bone rotation, how to define angles which bone is allowed to rotate? LookAt in UDK had something like that, as documentation [says][1]. Currently rotating it as shown on image below.

Had to set pitch value to 90 to block pitch rotation and make head positioned “right”, is there a better way to achieve it?

Hello there, currently trying to implement head rotation driven by mouse movement.
Getting rotation as shown in the picture below

And setting rotation as shown in picture within my comment on Ray’s answer, using replace method to set rotation.
So head rotates with out any limitations and i could not find a way to properly lock it. Tried simply checking values and setting yaw/roll/pitch to maximum locked values, that didn’t work out, it was barely working at all. Also if i change character direction via WASD movement head rotation messes up even more. What would be a proper algorithm to achieve head rotation of this kind? I assume head also should be rotated somehow relative to character rotation as well. Appreciate any help, thanks.


personally I’m using the third person template and simply wanted to transform a bone. I did exactly what you described and whatever I do I never see anything changed. I chose a proper bone from the HeroTPP and did what you did in the anim blueprint but nothing changes.

What am I missing ?

Thanks in advance

Well nevermind I just found that ‘Rotation mode’ property was set to ‘BMM_Ignore’ by default… Good to know for those others like me who have no clue what could be wrong though.

How did you get the “Mouse Location in World Coordinates” node?

I tried this thing also in my project but its not able to replicate. Do you know why? Variable is set to replicate.
Im getting the rotation out of “get controll rotation”

I did this using what Biggest Smile uploaded, worked for me, All I wanted to do was rotate the head just a little to have it straight up and down. Hope this helps anyone with my problem! Cheers!

this really helped me in 4.14.1… I set up the character anim so that he still uses the leg movement anims but his spine_03 bone (which has the arms and head) can look up and down, however I hooked up his look up and down movement to the controller aiming