I was a bit surprised by this article as it actually contradicts the account I always heard, which was their main vocal effect was a Roland VP-9000. If you listen to e.g. Harder Faster the effect is somewhere in between a vocoder & autotune, so I assumed that was the VP-9000. That said, this guy has clearly done his homework (pun intended) so I'm inclined to accept his version of events.
It’s hard to know without an official word from our favourite robots, but I think you’d struggle to get the sound of any Daft Punk song out of a VP-9000. I’m really not sure where that rumour started.
I almost bought a VP-9000 to test, but sonically it’s so far off, I didn’t bother.