Keyframing face controls in UE (Sequencer or otherwise)?

I’ve imported a character from Character Creator, and the face controls/sliders import with it, and obviously work when looking at the character itself. How, then, do I go about animating/keyframing those sliders? From what I can tell you can only use mocap for character animation (although I’m trying to get my head around the control rig). Is there not a way to add additive tracks like in Motionbuilder or Maya, so you can have the basic mocap, but then do an additive to raise the arm (or whatever–rig control animations), and keyframe the expression sliders? I imagine this is a pretty basic question, but parts of the answer seem to be scattered all over the internet–I haven’t been able to find a concise-in-one-place comprehensive answer to this.


Assuming you’re using Se1quencer: Add another track and set its property to Additive

This sounds like what I’m looking for–but where do you choose “additive”? I see changing track weight, so I assume they’re all probably additive anyway. I also just found the option of adding an FK rig track, but when it’s on the same character as an animation it overrides the animation completely. How can I get them to live harmoniously? And to access joints other than FK (including face expression sliders) do I have to build a control rig from scratch?

So many questions. Thanks for your help!

Click on Control rig track where it has the +
When hovering over the + that twill say +Section
Click on it and Select Additive from the popup
When you hover over the actual track area it will say additive
Now change that control rig and it applies to an additional motion to whatever was already on the track(s) before. (Including bake animation, etc)

You can also do this with transform tracks to make another transform which is additive

In theory this is working, but in actuality the minute I do a track with the FK rig it still kills all other animation. You can see by the screenshot here that I did edit the section/change to additive. Whether I add the animation before or after the FK animation the result is the same–the FK rig silences everything else, so there must be another step to making it additive that I’m missing, correct? (Those two keyframes are just a quick head turn to make sure that part of things works, which it does.)

Aha! By watching one of the 2-minute “new animation feature” videos from Epic at 0.5 speed, I was able to see them do the “bake to control rig” click. Doing that worked just fine–I expected we’d be able to add on top of clips, but this hardly seems an inconvenience.

You can just add a control rig and make it additive.

That has never worked for me. As soon as an FK rig is added, even if the track is “additive” (both in creating it with the + and in the properties), it kills all the other animation. I’ve tried both ways to no avail.