Saturday, January 19, 2008

Roomba: Not Your Mother's Vacuum Cleaner

Robert A. Heinlein Scores Again!

In his classic time-travel novel, The Door Into Summer, Robert Heinlein's engineer protagonist Daniel Boone Davis invents a mechanical cleaning robot — not a humanoid device that dusts and pushes the vacuum cleaner, but a smaller gadget that runs around the floor looking for dirt, picking it up and returning to its charging station when it is full or it runs out of juice.

The device is promising enough that his scheming girlfriend and unscrupulous partner conspire to trick him into taking the "long sleep"; they freeze him and send him into the future. The rest is grist for a wonderful story.

But what happened to the wonderful cleaning robot? Other conceptual gimmicks (waterbeds, ATMs, manufacturing robots) from Heinlein's fiction have become reality. Where is the floor-cleaning wizardry we were promised?

iRobot has it — when I first started looking at the Roomba, and its partner mopping machine, that Scooba, I wondered if the patents had the name D.B. Davis on them. Here it was, that all-around time saver of a semi-intelligent vacuum cleaner. The Roomba Red is the basic version. At the push of a button (and a bleeping Tally Ho!), it starts out on a drunkard's walk around the room, flicking and sucking dust, pet hair, crumbs, etc. into a small cannister. A sensor looks for concentrations of dirt; when it encounters them, it switches into a spiraling pattern designed to focus on the dirty area. Another sensor backs it away from the brink of stairs.

Yep, you can turn it on and walk away. It will clean as long as its battery has power, and there is still room in the cannister for dirt. Unless it gets stuck. Or high-centered on something. Or plugged with something it can neither suck in nor disgorge. Even then, it has a plaintive little beeping song that tells you your Roomba has problems its chip can't solve.

Rather than walk away, I like to watch the little sucker work. It rolls easily up over non-fringed carpet edges, and has a back-and-turn trick to deal with the problem when a carpet edge gets sucked into the brushes. It bounces off of obstacles, then stubbornly returns just a touch to the left or right to see if it can get past. The circling movements when it runs into the out-trackings of the cat's litter box, and the sometimes-panicked, sometimes-stalking behavior of my cats, are fascinating.

When it can't complete its task because its bin is full, the Roomba halts wherever it is and plays a sad little "Oh, no!" melody. And its triumph when it returns to its charging station, finished for the day, is evident in the "Ta-dah!" it bleeps into the room.

Oh, you still have to pick up the bigger stuff before you set the Roomba loose — in my case, cat toys, books, and the occasional sock. I still have to hand-brush the fringed carpets; the Roomba just tries too hard to suck up that fringe. And although the Roomba Red has to be started manually, there are advanced versions that start on a timer, and they all run from hardwood to carpet, sweeping as they go. (For wet-washing floors, you want the mopping robot, Scooba.)

So Heinlein can put his feet up on a cloud, and chalk another one up on his predictive scoreboard. I'll just put my feet up down here, and watch my Roomba clean.