Vehicle jumps up and falls down when hit obstacle


It was observed that when vehicle hits an obstacle, it jumps up and falls down, wondering if this could be problem with suspension system?

Thanks in advance!

It’s very difficult to diagnose the problem without more information about the issue reported.

Do you mean that the vehicle’s collision hull hits an obstacle and then the vehicle jumps up and down? That would be unexpected behaviour.

Or do you mean that one of the suspension raycasts is suddenly blocked by an obstacle underneath the car and the car then jumps up and down? That is expected behaviour because the suspension will be kicked upwards for a few frames and the vehicle will move with it. It is, of course, unwanted behaviour but raycasts have their disadvantages as well as their advantages. There are multiple ways to fix this. The first is to use scene query filtering so that the suspension raycast ignores the obstacle. If you want the obstacle to move when the wheel hits it then you could add a collision volume for the wheel and use simulation filtering to ensure rigid body contact between the obstacle and the wheel. The second fix is to use the volumetric wheel feature introduced in 3.4 and illustrated in SnippetVehicleContactMod. This uses a combination of sweeps and rigid body contact for the suspension and switches between the two based on the contact point and normal.