@Xenobert: We know why he's called Ruebert and it's obviously a pun on robot. @Jimson is correct though I don't know why he puts a '?' at the end of his comment.
This is not a pun on robot. Alot of SA's characters end in 'bert'. Dilbert, Dogbert, Ratbert... Since this robot rue's the day he was created, Dogbert felt "Ruebert" was fitting.