How do you stop a robot uprising?
That’s just one of the disappointments I discovered when I tried to find out whether robot vacuums can actually clean. A dozen years after the first Roomba robo-vacs made their debuts, today’s models top out at $700 and tout improved power and navigation. One even has the same technology found in Google‘s GOOGL +0.08% self-driving cars.
I lined up three of the latest—the $700 iRobot IRBT -1.25% Roomba 880, $600 Neato BotVac 85 and $500 Moneual Rydis H68 Pro—to test in my home and in the Journal Thunderdome, a pen I built to compare performance. On shag, medium-pile and low office carpet, I made them gobble Cheerios, M&Ms, beach sand—even potting soil.
The result: None of the robots are good enough to replace a manual vacuum. The idea of a robo-cleaner may appeal to slackers, but just keeping one running is hard work. At best, they’re a pricey supplement to clean homes with a lot of pet hair or dust, and best used between regular vacuuming.
All of them were stymied by 1-inch shag, and none could muster the suction needed to pull sand out of medium-pile carpet. Just hunting for dust bunnies, all the bots got tangled up in power cables and caught in furniture.
Today, some 15% of world-wide vacuum sales are bots, according to industry researchers. But let’s be honest about why many of us get these little fellas: They’re adorable. Watching one auto-navigate its way out of a tight corner is like watching a puppy climb stairs. I understand the compulsion to name them and dress them up in outfits.
Snap out of it, people. None of these robots perform like Rosie from “The Jetsons.” If you spill Cheerios on the floor, just grab a vacuum and clean it up yourself. While robots will one day get intelligence to spot messes from afar, the ones I tested don’t have it.
Robot-makers have two approaches for how to navigate a floor. A Roomba bumps around in a seemingly random pattern, on the assumption that it will cover every spot at least three times. It gets help from sensors that guide it around walls and away from stairs, and suggest it linger when it sees, or even hears, extra dirt below.
BotVac and Rydis are like Roomba’s obsessive cousins. They use sensors to map out a room and then methodically follow a path to cover it. BotVac uses a proprietary laser scanner and navigation technology like in driverless cars to clean the house in 15-foot-by-15-foot chunks.
Neither approach is perfect. In my tests with Cheerios and M&Ms sprinkled across carpets, none of the robots managed to scoop every morsel. The D-shaped BotVac has the most powerful vacuum and largest dust bin, but got confused and frequently ignored whole sections of my carpeted test pen. Rydis, which has the least effective vacuum and smallest bin, chewed up the Cheerios like Cookie Monster—leaving behind a bigger mess. (A Moneual spokesman said Cheerios are a little too large for its vacuum, and its prime targets are dust and hair.)
Roomba and BotVac proved equally effective at finding chunks of food on low office carpet. In 45 minutes, they gobbled up 2 cups of Cheerios, leaving only a bit behind. But if you were relying on either to clean, who knows how long those missed Os might remain on your floor?
Sand revealed a second problem: None of these robots have sufficient suction. I poured 4 ounces of sand onto fresh 5-foot-by-7-foot carpets, and no robot could retrieve even an ounce in 45 minutes. Letting them run longer yielded little additional sand. The companies say their bots can carry only a fraction of the suction power of a plugged in upright vacuum. “Robot vacuums are a supplemental accessory, used to lengthen the time between serious vacuums,” a Moneual spokesman said.
And then there’s the shag. The robots would stagger, seize up or report unseen obstructions. An iRobot spokeswoman said no robot vac is “ideal on higher pile or shag carpets.” The other makers echoed that sentiment—but none of them strongly emphasize on their websites, packaging or manuals that they don’t work on this very common floor covering.
Roomba and Rydis fared better on medium-pile area rugs, but BotVac even disappointed there: Its wheels would slip, rendering the BotVac’s laser-guided smarts irrelevant.
A Neato spokeswoman said that the carpet I used for the test—a budget area rug from Home Depot HD -0.11% —was made of waxy fibers that caused BotVac to lose grip. Whose fault is that? (The robot performed better on office carpet and hardwood.)
These robot vacuums perform best with lightweight cleaning in spaces where the main culprits are dust and hair. All three bots were able to find an embarrassing volume of dust bunnies on the hardwood floors in my “clean” house.
Because they’re short, they can generally find their way under sofas and beds to places few people remember to reach with regular vacuums. They can be scheduled and they charge themselves, so emptying their tiny bins is all they ask of you.
But they got themselves into enough trouble in one week in my house that I’d feel uneasy about letting them run unattended. Roomba chewed up paper it found and managed to lodge itself under a chair. Rydis became unresponsive to controls, trying to push into a wall. And the particularly aggressive BotVac gobbled up an errant phone cable it found under a sofa—and pulled another gadget off a shelf by grabbing its cord. The companies say owners get used to prepping their houses to be robot friendly. “People need to partner with their robots,” a Neato spokeswoman said.
If your house is clutter-free, these robots may do OK, especially if you set up virtual guardrails. But sorry, I don’t have time to clean up my house before they do.
If I were to choose a robot to zap dust bunnies in my own house, I’d pick the Roomba for its balance of performance and floor-type adaptability. But at $700, that’s one pricey dustbuster. The more basic Roomba 630 sells for half the price, though its brushes aren’t as good at handling long hair.
I look forward to a time when robot vacuum cleaners are as effective as their upright ancestors. At that point, I will buy one—and probably dress it up as a turtle. But that future has still not arrived.