Some people think we could easily build and identify a conscious robot, while others insist that it’s impossible – it all depends on what you think consciousness is.
There is disagreement over whether machines can ever be conscious, let alone how we would know if one were. Your view may depend on how you see consciousness.
If the subjective feeling of consciousness is an illusion created by brain processes, then machines that replicate such processes would be conscious in the way that we are. How would we know this? Daniel Dennett at Tufts University in Massachusetts thinks a Turing test, in which a machine has to convince a human interrogator that it is conscious, should, if conducted “with suitable vigour and aggression and cleverness”, be enough.