How I can make gameobject detect collisions and make every other gameobject be able to go through it?

[system]

I'm trying to make hidespot(invisible box object) to my character, but it doesn't detect collisions if either my character or hidespot have rigidbody. Character doesn't need to have rigidbody so I made rigidbody to my hidespot. It works fine, but when enemies with rigidbodies tries to go through the hidespot they crashes to it and often got stuck. I would like my hidespot be able to detect collisions but also allow objects go through it.

[efge]

You could use a trigger and the function OnTriggerEnter to detect if a Collider enters the trigger.