Chaos vehicle wheel width has no effect

Hi, so no matter what value I put it doesn’t seem to affect anything, like I can put 0.01 to 100+ it’s not doing anything, can someone explain if this setting has any effect on wheel behavior/collision ?
Wheel radius working just fine and you can see the difference.

Thank you.

Hi Kaidoom,

Cool question, I’ve been keen on understanding Chaos Vehicles better, so I tried looking into this.

In https://github.com/EpicGames/UnrealEngine/blob/release/Engine/Plugins/Experimental/ChaosVehiclesPlugin/Source/ChaosVehicles/Private/ChaosWheeledVehicleMovementComponent.cpp (You must link your github account to Epic and be logged in to see this)

I found 2 instances of WheelWidth

  1. float Radius = PVehicle->Wheels[WheelIdx].Setup().WheelWidth * 0.5f;

and then that ‘Radius’ float was used for some line traces. I wonder if someone has confused Wheel Width (How fat a tire is, as in length of contact patch) with how wide a rim is.

  1. In a block of commented-out code for calculating WheelDimensions

I realize that isn’t particularly helpful, but hopefully it can unlock some new ways on our paths to grokking Chaos Vehicles. :brain:

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Thank you for responding.
I’ve been looking in that section as well, from my understanding they use a line trace or a sphere trace which you can’t really incorporate radius and width as the same time.
You can select what to go for in the ChaosVehiclewheel class, I don’t think shape cast is used though.

Here’s the result when using a simple ray cast trace, you can see the issue with the wheel on the right, from a line trace perspective everything is good.

Sphere trace solves the issue but you still get some situations like this with wider gaps.

I think wheel width can only be used with something like a capsule trace perhaps.

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I want to correct one thing about sphere trace, this is mainly the issue you would face with a sphere cast, since the sphere sticks out more to the sides the wheels will hit the curb when driving near it even though it shouldn’t in regality.