Help - Control Rig Look / Point at constraints

I imported an FBX from Daz3D that features “look/ point at” constraints.
These basically tell the bones to always be rotated towards a specific target point.
I have uploaded an example video of how it should look, the bones in question are the “neck pistons”.

Of course these constraints no longer exist when importing into Unreal.
I tried to recreate the effect with a Control Rig, but so far I could not find a solution.
Here is a short video that shows the problem:

As you can see, the Debug-Line I draw is the optimal line the bones should follow / be rotated along.

It is actually a simple line from Point A (Blue Bone Control) to Point B (Green?/Yellow? Bone Control color blind sorry)

However, I simply cannot find a way to solve this.

Does anyone here know how I could achieve this? I tried the Aim-Node to make the bones aim at each other, but that just screws everything up.

Hi svenji
Did you manage to resolve this?
I have the same problem, in 3dsmax it’s called “Look at Constrain”.
I also couldn’t figure out what similar command in Control Rig.

Sorry for the late reply I was not active in this forum in forever.

I did actually figure it out.
The best way to handle this in unreal engine is to use physics body constraints.

For my example above I solved it like this:

  1. Attach a physics body to the small piston
  2. Attach a “bigger” physics body to the “tube” it moves into
    I chose 2 rectangular bodies here.

You can then constrain these physics assets. Tell them in which direction to move and lock an axis or two.
You can also set different parameters on how much “wiggle room” each piston has.

Sadly I deleted the project, but if you require more help, I could try to see what I can do.

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