btRaycastVehicle jitter

[dwells254lb43]

Hi, I am using the btRaycastVehicle and when I have it on the ground (another btRigidBody) it jitters and bounces around, this makes the vehicle very unstable especially for very small vehicles. Any ideas?

I am also just using the size and information from the vehicle demo, and when i get close to the object its quite apparent of its seizure.

Thanks

[mirat]

I met with the same problem. Try to reduce size of the ground body, ray casting goes unstable on big meshes. I had to construct the landscape from small tiles.

Another workaround is to use gimpact triangle mesh for ground collision shape. I don't know why, but I get more stable vehicle on gimpact instead of even convex ground mesh.

[Verbo]

Hi,

Yep, large convex mesh and raycast vehicle are not good friends. We had the same issue in the vehicle based game we are working on. The easy fix we did was to use btBvhTriangleMeshShape for all our fixed ground parts.

However, we are still using kinematic rigid bodies for some moving parts, so we are still watching for the problem to arise, because we are not sure yet if we can use btBvhTriangleMeshShape for kinematic objects...

Verbo

[CodeWarrior]

Breaking on all (four) wheels causes jitter when vehicle is standing still.

[fishboy82]

Yep,because the large size of the ground shape will make the convex cast algo used in wheel-cast unprecise, so you will see the wheel jitter, the easiest way to get rid of this is to use triangle mesh to represent a large size ground shape,for example use 100*100 triangle mesh to replace a large box shape ground object ,this will get rid of this problem