How to make things Unity Character Controller player steps on move according to physics?

For instance, if my Unity Character Controller player crosses a rope bridge like this,

then how would you make the planks of the bridge move under the player's feet?
If you just put a Sphere with Rigidbody then the planks move automatically, but since my Player doesn't have a Rigidbody then I'm not sure how to achieve this?
Thanks.

 

You would have to create your own logic of this or somehow fake it with additional gameobject with kinematic rigidbody and capsule collider following your player...
Obscure solutions aside, I would recommend not to use CharacterController component if you want to have complex physics interactions. Just use a rigidbody controller, you can create your own or scrape some on the internet. There was one provided by Unity even but I can't find it any more on their site, but Brackeys used it in this tutorial:

and here's the rigidbody controller:
https://github.com/Brackeys/NavMesh-Tutorial/tree/master/NavMesh Example Project/Assets/Example05 - LowMan/LowMan/Scripts