There are many different kinds of robots, so you can determine what “robot voice” means to you, though it should probably sound different from your regular voice (unless you’re a robot, I suppose, in which case I for one welcome our new robot overlords).

If Impounding Lot-Bot leaves the battlefield before its enters-the-battlefield ability resolves, the target artifact or enchantment won’t be exiled, even if you say INCARCERATE! You should say it anyway though.