I recently heard that Roombas often freak family dogs out because they don't know where they stand in the pack order. Here's a new "creature" that doesn't seem to follow orders or help the family pack. A tip from a dog trainer was to let your dog see you "disciplining" the Roomba to re-establish pack order.
I hadn't thought about it from that point of view! He isn't overly traumatized, by any means, and it genuinely does entertain us. Before you think we're totally heartless, when we run it, we do leave the pocket door into the next room open 8-10" -- enough for him to escape, if he chooses, but not enough for the Roomba to get into that (linoleum -- no vac needed) room.
If it becomes an issue, I can see "disciplining" the Roomba . . . but wouldn't the dog think we're lax disciplinarians when the Roomba never obeys, and we don't force the issue? We were pretty strict with him when he was a pup, and now he's a well-behaved critter. Would he think we care for the Roomba more than for him? I suspect I'm attaching more thought to the concept than would the dog.