I know full well I can just read the manual or Google the questions I have when it comes to how 2 Roombas will interact in a small environment, but I have so much more fun black box testing and theorising how something works. Besides, the most exciting phrase in science isn’t “Eureka!”, it’s “Now isn’t that interesting”.

All that said, into the badlands I go to see how they interact. Keep in mind I’m deliberately not Googling or RTFM’ing.

So the Roombas can be prevented from wandering too far by erecting one of these towers. How they work is pretty straight forward I guess, it’s invisible and directional, so probably not radio based. More than likely infrared. Now while my arduino is out of commission I won’t be capturing any IR anytime soon, but the day is saved by my cell phone.

For some reason (which I’m just going to put down to a need to operate in low light condition) the IR that is normally deliberately filtered out or just isn’t picked up by normal cameras and the human eye is quite easily picked up by the humble cell phone.

So that little purple light there is blinking away at me. Looking at the casing of these towers, it looks like I’m right.

Actually, if I record the video then apply a nifty little algorithm (which for some reason I can use but can’t remember the bloody name) I could record or decode it then save it as an audio file replay it through my my phones headphone port into an IR LED to recreate it. Light to sound to light More on that later.

Back to the cultural workings of our robotic tribe. The villagers have boundaries and respect them. Let’s take a look at their home. While I have 2 charging stations/docks/huts for these guys, I’m only going to work with 1 for now. Again looking at our cell phone you can see the IR blinking away.

In fact, you can see 2 of them pointing off on 2 different angles. So it looks like each of these base stations have a directional beam at 30 to 45 degree offsets to create a V shaped homing beacon. Now the strange part is that in both situations, I didn’t really expect the IR to be coming from these places.

So now I find myself wondering what the hell is this thing? There’s one on each device and the Roombas too. It’s a reflective inverted cone in a clear housing. So it’s either for focusing any light in a 360 degree view into a single receiver or sending a light from a single point to 360 degree spray. We’ll come back to that in another post.

So, these Roombas have homes but how do they feel about sharing? The easiest way to find out is my favourite part. Experimentation and observation. This is where it gets into the anthropology a little more.

I know from an earlier experiment that Roombas are a bit slutty. Any port in a storm. They don’t care whose dock they use. But when 2 Roombas vie for a place to call their own, it appears second place is a very bad thing. As soon as one Roomba occupies the dock, it covers the docking IR and leaves the other Roomba out in the cold. Out of sight, out of mind the lonely Roomba wanders off looking for a home. The loser in this game of musical chairs is unfortunately sentenced to death as it wanders into the wilderness looking for the home it will never find. Slowly it loses charge and dies.

This is a horrible thought really and I’d feel super bad about the whole thing (in fact I did feel bad and retrieved the poor lost little guy) but then I took a closer look at our noble worker.

That evil little bastard has been watching me. Both of them have. This entire time. LOOK AT IT!!! THOSE SUNKEN DEMON EYES!!! Now I don’t feel so bad at all. Yes I know that those are IR emitters, but I’m going to assume there’s a receiver there to pick up reflections so it can anticipate walls (which it then slows down before bumping). Technophobia aside, with a fresh fill of Robo-hatred I’m good to subject it to some more torture.

Roombas are, in fact, inconsiderate assholes. I mean, we’ve established that they can both see each other and yet neither one wants to concede and allow the other clear passage. Like Robin Hood’s first meeting with Little John, it’s going mean a butting of heads. So now that I understand just how bad these demonic asshole sluts suck, I don’t feel anywhere near as bad when I put one in a tiny room with no doors (in my opinion the most understated and epic threat ever delivered considering it was death himself who spoke it).

While my disdain for these horrid robotic imps has garnered the application of torture a little easier than I would like to admit it appears that, when faced with a small room and no way out, lady luck smiles on them still. The corner swiffer along with their nature, either through great programming or dumb luck, lead the Roomba to gently nudge the walls of it’s invisible prison until it Shawshanks itself out of purgatory and off to fornicate in the warmth of the closest charging station. Yours, mine, Roomba 2’s, or the neighbours.

In conclusion, I’d say the Roomba are a robust tribe of workers who display a blatant disregard for their own kind. A selfish robot with loose morals and little intelligence. Screw these little assholes.

Next post: Building the arena…