Character/Ragdoll deformed when Simulated Physics is enabled

Hello, i’ve made a character using blender and i’ve exported it to the engine. Animations and collisions work perfectly but the problem is that when i enable Simulated Physics it starts to deform.

This is the character i’ve made, before enabling simulated physics:

and this is what happens when i press simulate:

88733-after.jpg

It starts flying around instead of hitting the ground.
Thanks in advance for the help.

Have you setup body constraints/etc in PhAT properly or are you using the default setup which the engine generated for you from the skeleton?

For Blender models I’ve noticed that the collision bodies shown in PhAT are often different from what the engine is actually using internally for simulating! Try this: start your game, run Show Collision in the in-game console after your ragdoll deforms and look at the collision it shows you. Are the collision bodies much bigger or much smaller than what you expected? If so, this could be a bone scale issue which I have on a couple of my Blender models too. Hitting “Apply Scale” on the armature in Blender helps in some cases.

I haven’t perfected my Blender workflow for phAT either so I’ll leave others to provide more general workflow recommendations.

I’m using the default setup. I’ve tried Show Collision but i couldn’t see any collision on the ragdoll or maybe they’re too small.

This could be the bone scale issue I was talking about. Try using Wireframe View (F1 with play in editor) or Unlit View (F2) while checking the collision, tiny collisions shapes should be much easier to see.

In any case, try applying the scale of your armature in Blender before export to see if that helps. (Be sure to make a backup of your previous blend files / uassets though, applying scale might ruin your animations or do weird things to your skeleton/animgraph assets)

Select your armature (in object mode, not pose mode) hit Ctrl A and select “apply scale”. (official docs). Take a backup of your current blend file first.

Have you confirmed the “tiny collisions” yet though?

How do i apply the scale to the armature?

I’ve checked using the wireframe view but i couldn’t see any collision. So i tried the apply scale method but unfortunately it didn’t work anyway.

Hmmm I’m out of ideas. If your ragdoll is exhibiting no in-game collision at all (on top of not showing any collision with the command) then I’d double check the collision preset. But if it’s colliding and deforming badly (just like in phAT) it sounds like a Blender to UE4 armature import issue. I remember seeing at least a few questions on Answerhub related to your issue, try searching for those.

One last thing I’d try is to delete the default phAT bodies and create a few bodies yourself with a simple body constraint for testing. This is to rule out issues with the default phAT asset UE4 created for you.

Hope someone can provide a solid solution for this!

I tried deleting all the collisions and making new ones but as soon as i add more than one this happens.

Thank you for your help.

Did you see this thread already? That may be the issue here as well.

I didn’t see that, i’ll take a look at it hoping to fix the issue.

Fixed! All i had to do was decreasing the export scale in Blender. Now everything works correctly.

89019-fixed.jpg