Will robots rule our world in the next century?

We are living in a world that every day produces some new kind of technology or device that helps us in our life. Therefore i wonder, when human beings will be displaced by any of this new technology? Maybe robots will be our replacement.

Some people believe that the possibility that robots will replace humans it is near by but I find this hard to conceive. It seems that humans beings only use around 20% of the capacity of the human brain.

Imagine what we could do if we use our whole brain? 

I guess that by the time robots are produced massively humans will have discovered how to used their entire brains capacity. 

Therefore Humans will still be more integrated in society than robots.

It is because what I stated before that I found unlikely that robots will rule our society in the next century, perhaps this will be an import part of our world but could never replace us.