As a Roblox developer it is currently hard to make good cars with cylinder wheels due to the fact that they start bouncing when going at a incline.
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If Roblox is able to address your issue, how would it improve your game and/or your development experience? Please be as specific as possible.
While yes it is a easy solution to switch to ball wheels, that how ever limits us big time in different ways. For starters we would not be able to set up working realistic camber as ball wheels would have the same amount of surface area compared to cylinders. Cylinders are the proper shape so we would be able to set up gutter runs. For those who don’t basically it means you have a indent in a turn that you can put your tire into so you grip through the turn, while this works with cylinder wheels ball wheels would ignore the indent rolling over it as if it was a smooth surface or pop out of the indent due to the sphere shape.
Feel free to include any other details. You can test this for your self using any basic chassis set up with cylinders.
This is how ball wheels behave Watch 2019-01-12_22-36-55.mp4 | Streamable As you can see they are smoother but cylinders should be just as smooth. We believe this is related to how the collisions are set up on a cylinder and we think that by fixing the collisions it would rotate properly even at high speeds.
If the problem really is the collisions, you could union the cylinder wheels and check ShowDecompositionGeometry in studio settings to view the collision mesh. From there you could set CollisionFidelity to Default or Hull depending on whatever works better.
We have tried this in the past as well as trying to mess with a custom mesh in blender with no luck. From what I can tell it would need to be rounder with more faces to smooth it out. Looking at the wireframe it is not a perfectly smooth cylinder as you can see some areas are wider than others. https://gyazo.com/519c1fef3acf928461dcb6085cb83798.gif
I have also experienced this behavior when switching over from ball parts to cylinders. For me this usually occurs at higher speeds far less the incline. I have tried using MeshParts but haven’t succeeded either no matter the collision configuration.
Cylinder collision in Roblox is not based on the mesh geometry, the solver interprets it as a real cylinder, perfectly smooth. So, using a mesh part with more sides won’t solve this. That being said, however, we are having stability issues with cylinder collisions, and are looking into it. Thanks for sharing, we will be sure to include this in our test cases.
Could you let me know how fast the car was moving, and the wheel’s RotVelocity, when the bumping started?
