I think that the critical aspect here is self consciousness, not just consciousness. I suppose that a device that can detect and respond to external stimuli could be termed "conscious," but this machine being aware of its own existance is a completely different matter. I'd say that if a machine was aware that it was a thinking, detecting, reacting entity, and fully comprehended the meaning of this (although no one can say if people even fully understand this), it could be said to be self conscious.
This aspect is what separates humans from the rest of the animal kingdom. All other animals, except dolhpins, can experience their surroundings, and react to them, but have no idea that they themselves exist.
I wonder what the machine would think when you turned it on...
Animals besides dolphins are self aware. Apes that are taught sign language refer to individuals, able to differentiate between you and me and themselves, if that isn't self awareness, I don't know what is.
What made you say only dolphins?
The biggest thing that seperates humans from animals is his or her ability to build and modify tools.
I suppose I forgot about apes, but even then, I think its only Chimpanzees that are able to differentiate between themselves and others. Most, if not all, other animals have no sense of self. When looking into a mirror, most animals will not be able to identify the reflected image as themself, but will behave as if another entity is there instead. I've seen videos online of cats hissing at themselves and attacking themselves in mirrors. So I still think that self awareness is a rather unique trait, only found in humans and a few other species.
In terms of determining if other animals have a consciousness, that is rather hard to do. Communication with other species is rather difficult, to say the least, and there is no way, other than psychological tests, to determine much about their mental proceses. And I agree with other posts, the question about consciousness must be more specific. The capacity for self awarness seems an important aspect of attaining consciousness, but there is certainly more to it that that.
I guess what I'm trying to say is I don't think we can define or determine self-awareness any more that we can consciousness. In my opinion, I would consider most animals self aware. Of course, that's the problem, it's just an opinion. We have very little understanding of the origins of thought and intelligence from the micro to the macro. We might as well be cavemen talking about how to build a rocket to the moon out of rocks fire and clay.
I think we've got a language problem here.
Do you mean concious - able to respond to stimuli?
A relay does this.
Do you mean aware - able to react differently to
sets of stimuli appropriate to a situation?
With programmed controlers, we've got this too.
Do you mean self aware - able to pass a Turing test?
This one is more a problem for a philosopher than an engineer.
You are asking the question. It is up to you to further define the awareness that you are attempting to create.