Robot Rock is not an example of using an instrument to create the auditory illusion of talking like the talking piano is. I’m pretty sure Daft Punk are just using a talk box. The talking piano illusion happens because you’re mixing the frequencies of the tones of the keys to match as best as possible the frequencies of speech. A talk box simply takes the sound from the guitar through a tube that’s then put into your mouth and you kind of “mouth” the words into a microphone, kind of like if your voice was the guitar but your mouth still makes the movements.