is there any solution ???

I have imported some 3d models from archive 3d site to my project and added rigid body component to them , but after I pressed run to test my game , I found them falling down and passing through the ground like there was no ground .

Can any one help me to fix this problem .

Hope some one help cause I can’t continue my proj with that problem .

Hmm, that is really strange, maybe try restarting your computer because, i just made a quick scene in unity with Terrain and a cube with a ridgid body attatched to it, what version of unity are you using? i used 4.3 so it might be a minor bug.

Check if you had not just put a cube as a surface and make it a terrain. If it is a cube, make sure it has a box collider around it. The only reason it would be falling through is because of a bug or it is not detecting any colliders.

If you are using mesh colliders and your model is a child of an emptymesh which has no geometry. Make sure that the mesh collider component is attached to the model itself, not the empty parent. Otherwise you’ll have to manually assign the collider from the mesh collider component and the position and scale might be off a little.

Yes J-F , i found them have no mesh collider -.- .

sorry guys i don’t know how i didn’t noticed that , i made a cube collider for them

Ty for the help J-F , Parzivell & HarshaK