I recently switched my project (full of metahumans) to UE5.4
Where I got my physics for the metahumans more or less correct in UE5.2 this is all going wrong again in UE5.4
It seems my metahumans are falling as ragdolls down, once physics and collision are set.
When retrying in 5.2 my metahumans fall suddenly down as ragdolls too.
Which never happened before. So I’m afraid something has changed on a deeper level.
These are my settings in unreal 5.2 for now, in a clean project, with a clean reimport of a 5.2 metahuman
I’ve always set the collision to this configuration before, without really understanding it. I never wondered as it seemed to work. Afterward, I added breast physics to it with constraints. But now, in this clean project I haven’t even touched the physics asset. It’s a clean import.
One thing I noticed with an older overweight version of the same metahuman is that the shapes in the physics asset in the old version are “kinematic”, while in the normal weight version, it was set to “default”. Changing this for all the shapes gave me better results in 5.4, but then the neck gets separated when adding an animation file to the metahuman:
I got physics working on the Metahuman body.
You have to change two things.
Set collision in Body skeletal mesh in Metahuman BP to Physics Only.
Then to fix the gap between head and body, go to Face and set Tick Group to Post Physics.
hey @Hype_Ldbg
This worked really well for me; it’s the best solution. However, now I’m facing another problem to make it perfect. The dynamics work fine and as I want, but I set them up on a Metahuman and used the bones from the corrective pose or driven pose. Now I’ve lost the driven pose (corrective pose) effect after adding the physics. Do you know if there’s a solution for this?
@Hype_Ldbg
Oh, I see. These are bones used to correct certain poses, like for example the glutes, which have a parameter in the animation blueprint that tells them how to position when the leg moves back. This way, the glute bone stays in a specific position to avoid deforming when the leg moves back. It’s also used for things like arm bending, where there’s a corrective bone in the biceps that makes the muscle appear to flex a little.
In Metahumans, there are several of these bones—some are used for the chest and others for the glutes. I used the chest corrective bone to create dynamic movement for the breasts, but by doing that, I lost the information that tells it how to move when the clavicle raises.
What I need is for the physics simulation to be applied after the corrective pose information is processed in the animation blueprint.
I hope this makes sense, it’s a bit confusing, but I haven’t found a solution yet, and it seems like it should be something simple to resolve.
Aha, now I got it! The term for this in my head is corrective bone transformations and I didn’t make a connection.
Corrective bone transformations and physics both work fine for me on a Metahuman.
The fact that they don’t work for you is related to something else.
Did you modify the Metahuman skeletal mesh in a 3rd party tool and have reimported it into UE?
If yes, make sure you duplicate the original Metahuman skeletal mesh, open it and set source file in the details panel to your fbx asset. Then hit reimport. This keeps corrective bone stuff and doesn’t destroy it.
I didn’t make any changes to the skeleton, I only edited a new physics file and applied it to the body. In this physics file, I added a shape to those bones (thigh_bck_r), made it dynamic, and applied a constraint to the pelvis. The simulation works fine, but the corrective movement no longer works
@Hype_Ldbg
I found a solution to my problem, although it’s not the one I would have preferred, but now everything works fine. The solution was to duplicate each bone I wanted to use for the dynamic simulation in the physics file, making them children of the respective original bones, transferring the skin weights to them, and then re-importing the body to update the skeleton. After that, I created the physics file with the new bones, and now everything works as expected.
Since I had also applied this method for the breasts, I had to do the same for the head because it’s separated from the body but shares some bones.
Thank you for taking the time to address this topic.
