iRobot's Unhousebroken Dirt Dog

This variation of the Roomba robotic vacuum is meant for garage and basement floors, but design compromises offset its low price

Editor's Rating:

The Good: Low-priced version of the company's popular Roomba stands up to garage and basement debris

The Bad: The robotic sweeper stumbles on bigger fragments and requires a close eye to free it from mishaps

The Bottom Line: It'll clean your workspace competently, but be prepared to watch it for an hour or so at first

Give iRobot (IRBT) credit for knowing how to capitalize on a hit. The home robot maker has sold more than 2 million Roombas—the automated, robotic vacuums that glide though living rooms in search of dirt with nary a hand to steer them—since the product's 2002 debut. Now iRobot is trying to make hay with a slew of follow-on products that aim to capture some of Roomba's floor-scouring magic.

There's the Scooba, a blue and gray disc that scrubs your kitchen. The company adapted a version of Roomba called Sage (it's green) to scoop up dog hair. On Apr. 10 iRobot released Verro, a line of pricey pool-cleaning robots. I'm in the midst of a series of reviews of robotic devices aimed at consumers (see, 4/18/07, "Hasbro's Fickle Butterscotch"). So I decided to put one of Roomba's offspring—the garage- and basement-cleaning Dirt Dog—to the test. But this canine ranked well below alpha status.

At a panel discussion on robotics in San Francisco on Apr. 11, iRobot Chief Executive Officer Colin Angle told me the company got the idea for Dirt Dog when it learned customers who had upgraded Roombas to better models put the old ones out to pasture in their basement or garage, where the vacuums could serve out their days trying to swallow the chunkier sort of debris that resides in a home's nether regions. Why not design a product that could snap up sawdust, dirt, and nails with aplomb? While at it, iRobot figured it could tap into a new market of men who had long been forced to sit by while their wives reaped the rewards of Roomba.

Underpowered Pup

"We tend to focus on the head of the household—the woman," says John Billington, a senior product manager at iRobot. "Unfortunately, it's the basement and the garage that end up being the play area for the guy."

So in September, 2006, iRobot released the industrial black and yellow Dirt Dog, which at $130 sells for less than many Roombas and features design touches meant to help it tackle what Billington calls "the male spaces" of the house.

Getting there took some compromises. Unlike the Roomba, the Dirt Dog lacks a vacuum. It uses counter-rotating brushes to sweep debris into its bin. iRobot also took away some of the software-controlled behaviors that help get Roomba unstuck from jams. The Dirt Dog also includes a lesser battery than most Roombas that also takes longer to charge—six or seven hours, vs. three.

What the product shares with the Roomba is iRobot's application of artificial intelligence to cleaning a room. After a few spirals in the center and a crawl along the walls, the disc-shaped robots estimate a room's size, then undertake a zigzag pattern around it to hit every area, using sensors on their bodies and wheels to turn corners and miss obstacles.

Choke Trawler

To test the Dirt Dog's mettle, I took one to a friend's garage workshop. It's populated by two table saws, bags of hockey and cycling equipment, and piles of planks in the corners. It was a sufficiently male space, I figured. The 17 x 15-foot floor was coated with sawdust, and scattered wood chips, dowels, and nails completed the mess. A child's red Radio Flyer wagon in the corner presented a formidable obstacle to navigate. Let's see the Dirt Dog tackle this, I thought. To play fair, we moved some of the bigger debris off the floor and stacked the planks in even piles in the corners.

The Dirt Dog's a snap to get going. I gave the battery an initial overnight charge, plopped the sweeper in the center of the room, and pushed the big "clean" button on top of the robot (hard to miss, since it's the only button on the product). The Dirt Dog, about the size of a round serving platter and 2.5 inches high at its highest point, emitted a little fanfare, then began spiraling out in search of dirt.

Three minutes later, though, this dog was panting. The motor audibly slowed, leading me to pick up the disc to inspect. Sure enough, a small block of wood thrown from a saw had become stuck in the brushes. In fact, similar chunks that ranged from a half-inch to and an inch-and-a-half long stopped Dirt Dog in its tracks two subsequent times during the first 15 minutes of my test.

Owner on Guard

To its credit, the product effortlessly swept up wads of electrical tape, a screw, the dowels, half the nails, and a months-old Christmas tree twig. It swept admirably through the sawdust, leaving clean swaths in its wake, and circled around the legs of the saws, getting in close. It even darted under the red wagon and emerged victorious.

But each time Dirt Dog stumbled or got stuck—and there were many mishaps in my 70-minute test—I had to stop and upend the thing, take the steps needed to release the brushes and free debris, then reverse the process to resume my mission. After more than an hour of this, the room still wasn't clean. For a product that's billed as a time saver, keeping a watchful eye on the Dirt Dog on its rounds could quickly become a chore. It would be quicker—and cheaper—to do the job yourself with a shop vac.

iRobot says the Dirt Dog encounters the toughest obstacles the first time around a room, when it's dirtiest. Subsequent maintenance runs should be easier. My test didn't include a follow-up cleaning, but I hope iRobot is right. It's novel to watch the Dirt Dog romp through a messy room, and iRobot deserves credit for making its complicated technology easy to unleash. But this dog lacks enough bite to merit a full housebreaking.

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