Problem with wheels collisions

[anonymous_user_e7bc502d]

Hello!
Recently I started to learn to use UE4. I wanted to make a simple working vehicle, but there is a weird problem with wheels physics: they don’t work.
I checked all solutions I could find, but nothing helped. In most cases the problem was about wheels’ location, but I checked hitboxes with pxvis collision command and they are in the right place. They even collide with the player camera in play mode, but they go through the ground and other physical objects. To test it I even tried moving all other hitboxes except wheels few meters up to see if wheels’ hitboxes are misplaced, but they aren’t. I checked skeletal mesh few times, but it’s not the problem.
Also: only wheels had this problem while the rest of the car interacted normally with physical objects.
I tried everything I found and I can’t see the problem, but it still doesn’t work. I use the newest version of UE4: version 4.24.0
Here are some screenshots:

[anonymous_user_e7bc502d]

@MostHost LA

By the looks of it, the model is probably not rigged correctly - your skeletal mesh is probably the problem.

Also, the wheel RADIUS is 47.5 ???
The diameter is a whole meter? 95 cm? what sort of car is this? O_o

you need to try and find the way to debug the wheel components. I can’t remember what command it is, but it’s something like showdebug.cls or it had cls in it for collision, I’m almost sure of that. Anyway, once you are able to render where the wheel component actually is at (because it’s not the wheel you see, the component’s collision is invisible in editor and a factor of your radius+width parameters for the wheel). you can move forward with testing.

While in there, make sure your PHAT has kinematic set for the wheels collision. maybe you just have no collision on those in Phat.

So turned out my all issues were caused by my horrible blender skills. (Including car’s size, it was supposed to be half the current size) Also it turned out wheels were at the bottom of the car also rotated wrong, but I don’t know how to fix this in blender. Will probably take some time, before I figure out how to fix it. Also thank you, that debug ccommand helped me a lot and will probably help me in future. Time to learn blender more

[anonymous_user_e7bc502d]

@MostHost LA

Pretty easy. Edit the bones and rotate them 90deg. On the X or Y axis.
the diameter/radius thing is not uncommon don’t feel bad.

For the car rig (basic) you want 5 unlinked bones.
root, and 4 wheels.
The 4 wheels have the root as their parent.

They should be positioned with X in front, Z above. You can change the display in blender to show axis for the bones and help you out a bit.

Before reading this I managed to move wheels to correct locations, but still need to change rotation. Also wheels’ collisions seem a bit small (I checked all sizes and should be correct, but I will check once more)

[anonymous_user_e7bc502d]

I noticed how rotating bones has no effect on it, but rotation joints does. Parenting is done correctly. Showdebug command doesn’t show wheels’ collisions anymore tho. I tried to do everything same as before, except I rotated those bones…

[anonymous_user_e7bc502d]

I did everything as you told me to, but wheels are still not there… I’ll redo everything following tutorial, maybe I missed something important

In the photo you can see what happened when I moved the body hitbox up. Wheels’ collisions are just not there…

[anonymous_user_e7bc502d]

So after trying to make it all again from scratch…
(Red sphere in the screenshot is not car’s collison, it’s there even if I delete car)

[anonymous_user_e7bc502d]

I figured it out myself and now I have working collisions and car is moving as well as I wanted it to.