Unusual Physics Behaviour After Migration To UE5

So I’ll get straight to the point, I made this trees in UE4 that are pretty simple.

You hit them → Simulate Physics → Impulse is applied to make them fall.

Simple as that and they work just fine on UE4, whoever, today I migrated the prototype to UE5 and the physics are making the trees go crazy when they collide with something.

UE4 Physics Working Fine: UE4 Prototype: Physics Working Fine - YouTube
UE5 Physics Going Crazy: UE5 Prototype: Physics Went Crazy - YouTube

I’ve tried to tweak the collisions(which are just 2 cubes), removing the grass, changing the landscape and tweaking the values on the Physics tab inside of Project Settings (which made things worse).

I’ll be honest I’ve been learning UE4 for 1 month, so Im still very new to this, so I might have made some mistake.

Also I dont know if Im posting this on the right category because I have never posted before.

Ue5 has the new chaos physics engine instead of the “old” physx engine perhaps this is the problem

Any ideas how to ease this effect or how to switch to the PhysX engine? I know that Epic intends to get rid of the PhysX entirely, but right now Chaos is really not helping me at all.
Any idea is a good idea right now, even if it requires me to retry everything I listed above. I can also share prints of everything if needed.

I was forced to almost completely stop working on UE because of this. I know 5 uses a new physics engine so I want to work with it and unfortunately, nothing works as it should. I don’t want to go back to 4 so all I can do is stop and wait.

This is really a sad thing. It’s like an entirely new engine as far as physics goes. But we already had ongoing projects made with UE4, we can’t just start over with a different engine. So, waiting…

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lol :smiley: that tree

I’m the last to talk about physics because I’ve spent like two hours looking at how it works but one thing I’ve found out is that you need to have correct physics materials applied

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I actually ended up fixing the problem and completely forgot about this post.
I ended up reseting the linear damping and the angular damping of my trees.
Apparently this all started bc I migrated my project from UE4 to UE5 and it probably broke some values. I recommend reseting the linear damping and the angular damping, since it has been a while since I fixed this, I kinda forgot what I did besides that but I remember getting mad when it kinda fixed itself when I reseted those 2 values. Also I have LOCK POSITION X and Y enabled on the trees so they dont move that much when the physics are enabled. Now they vibrate a bit on the ground and thats it, barely noticable. Also check if the physical material that is applyed on the floor or wherever surface you are having problems and remove completly the physical material. I also had one when I was facing this problem, didnt add one again bc it was not needed for my game.

If you want to make slippery floors or bouncy surfaces that is that right thing to use. Also if you wanna do different footsteps based on the floor you are on, lets say mud and rock, you can use Physical Materials to change the sound of your footsteps. Didnt really got into it yet but thats all I know about it :slight_smile: