How to make an object(cylinder) always at the center of an object(Terrain)?

I have a cylinder that have rigidbody. So what I want to do is make the cylinder roll down and make its position in the middle of the slides(boxes), and rotate itself depending on where the slides are leading to until it reach the end. Please help me.

 

It should do it by itself, you need to put a custom mesh collider to it, and attaching a physics material with high friction, but it should do, if you don't want to make a custom collider, attachibg a sphere collider, and freezing z or x rotation should also work

 

Oh, I see, you could solve this with invisible walls, or positiom freezing.

 

ohhh thank you so much