Irrlicht Engine

Hi

I had collision detection working early on in game development but there was a massive drop in the frame rate. I now have the following function to simplify things but nothing happens

CGame::WorldCollision(ISceneNode* node)
{
ISceneNodeAnimator* anim = temp_smgr->createCollisionResponseAnimator(
selector, node, vector3df(20,20,20),
vector3df(0,-50,0), 50.0f,
vector3df(0,0,0));

node->addAnimator(anim);
anim->drop();
}

Using function in main:
WorldCollision(bot[0]);

can anyone point in the right direction as 2 why nothing is happening?

can know one help?