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Gadget Review

Roomba Intelligent Floor-Vac from iRobot

By Kailas Narendran

Staff writer

Why toil endlessly to clean up the floor of your apartment when you’re just going to get it dirty again? The answer to this question divides the population more than any political or religious controversy (kind of like the question of “Do you like Harry Potter?”). On one hand you have the “dunno” and “amen brother!” and on the other you have “because” and “it’s disgusting.” I have to say I was in the former category till I saw the Roomba Intelligent Floor-Vac from iRobot.

The Roomba is the world’s first robot vacuum cleaner. You simply put the device in the middle of the room and select a room size (small, medium and large). After that, the Roomba takes over, driving around like a tiny, robotic housewife, cleaning the floor.

How the Roomba works

The robot starts by spiraling outward from the center of the room. Once it runs into something (sensed by the bumper on the front end), it starts a wall-following algorithm using the bumper and proximity sensors.

A small spinning brush picks up dirt off the corner, pushing it into the path of Roomba’s brushes. After a bit of wall following, the Roomba starts to cut across the room in a somewhat random pattern, cleaning as it goes.

It has sensors on its front end to ensure that it doesn’t drive off a step or any other dangerous architectural formation. The wheels are soft, knobbed rubber, allowing it to easily traverse all types of flooring (I tested carpet, tile and hardwood), and transitions without getting stuck.

It runs off of rechargeable NiMH batteries which are good for about 45 minutes to an hour of continuous operation (enough to clean two or three good sized dorm rooms, assuming no carpet).

There’s also a small catch tray that’s easily removable for emptying the robot.

Roomba beats out competition

When I first saw the Roomba, I was skeptical of its functionality. I had used handheld, battery-powered vacuums before with very limited or almost no success. Products such as the Dust Devil required me to cover the same spill about 4 times to actually pick anything up. The Roomba does a much better job for a couple of obvious, and not so obvious, reasons.

First of all, the Roomba has rotating brushes (bristle and a rubber one), that help it pick up all the crud off of both hard and soft surfaces.

But the subtlety that allows this battery-operated vacuum to do such a good job is that it can mindlessly cover the same ground over and over, picking up a little bit on each pass.

While this would be boring for most people, the robot does it with no complaints. This subtlety is how they can cram the value of a vacuum cleaner that could easily cost hundreds of dollars into this unique, reasonably priced unit.

Putting Roomba to the test

I put the Roomba through its paces in my apartment and it fared quite well. The floors are mostly hardwood, with a couple of carpets placed here and there. The robot had no problems with the transitions between surfaces, and ended up covering the floor quite well. The small catch tray wasn’t a problem, either. The first time we ran the vacuum we had to empty the catch tray a couple of times. But since it’s so easy to use, I run the Roomba every other day and there isn’t enough time for more than one tray’s worth of debris to accumulate.

The unit does have trouble when it goes over loose cables. They tend to get caught in the brushes. Five minutes of work tidying up loose cables and rug tassels quickly makes a room “Roomba Friendly.”

A “virtual wall unit” is provided with the robot and allows you to set up an invisible wall wherever you want. I found this unit to be very imprecise, creating a wedge shaped wall rather than a linear boundary. I often find that it’s easier to just put a box or chair in the way of a door I don’t want the Roomba to pass through. The charge on the battery is plenty for a room up to a few hundred square feet.

Overall, I think the Roomba is a nifty piece of technology. Its underlying principals are simple, but the emergent behavior is pretty impressive. You can buy it from a variety of retailers including Brookstone for about $200. You can find out more information at <http://www.roombavac.com>.