Time for action – making the mesh colliders convex
Provided our mesh is made from fewer than 255 triangles, one thing that we can do to make our Mesh Colliders behave better is to mark them as "convex". (You can see how many triangles comprise a mesh by clicking the mesh and looking at the Preview section of the "Inspector" panel.) GameObjects that are in motion (like our HandsAndTray soon will be) tend to react better with other moving colliders if we make this small change.
In the Hierarchy panel, hold down the ALT key on your keyboard and click on the grey arrow next to the HandsAndTray GameObject. Instead of just expanding the top-level item, this expands the entire tree beneath the parent GameObject.
Select Hands_Mesh.
In the Inspector panel, under the Mesh Collider Component, check the box labeled Convex.
Do the same for Tray_Mesh.
As we did with the paddle before it, add a Rigidbody component to the HandsAndTray GameObject, and check the Is Kinematic box in the Inspector panel. As...
