It seems that everyone is on the hunt for the perfect robot vacuum – they busily clear away crumbs and piles of dust, wielding their brushes, rollers and even mop attachments in every corner of the apartment, all the while you cook your dinner or help your children with their schoolwork. But can this automated helper really replace your weekly cleaning routine?
These gadgets can certainly be helpful, but don't expect them to be able to get the job done on their own.
"Most robot vacuums manage a basic cleaning of the floor, but many models do not reach into the corners," said Anne Kliem, who recently tested various robot vacuum cleaners for the German consumer organization Stiftung Warentest. The lateral brushes often aren't suitable to clean tricky areas, she adds.
In addition, not every robot fits underneath cupboards, beds and sofas. "Buyers should measure the space below their furniture before purchasing a robot, to make sure that it can reach below," said Markus Nohe, product expert at TUV SUD, a Munich-based technical inspection association.
Most robot vacuums are either great at cleaning carpets or hard surfaces, but not both, testers for Stiftung Warentest found. Especially more affordable models have problems on one of the surfaces.
"For carpeted floors, the device must have a brush that penetrates deep into the pile," Kliem explains. Otherwise, the dirt is only removed superficially.
"On hard floors, the lateral brushes shouldn't rotate too fast, otherwise the dirt will be pushed away,” Kliem adds.
Robot vacuums have sensors that allow them to find their way around the room and detect obstacles. Navigation often takes place via lasers or cameras. But even this has its weak points: "Laser models are easily confused by reflective surfaces – cameras struggle with orientation in poor lighting conditions," explained Nohe.
If you don’t want to tidy up every time before sending the little helper on its mission, you are therefore best advised to avoid a mess in the first place.
"The fewer items on the floor, the faster the cleaning process becomes overall," Kliem said. Socks strewed all over the place, yesterday’s newspaper lying around or small toys under the sofa: All of them can obstruct the vacuum process and cause malfunctioning.
However, the little robots are doing a better job in terms of frequency than we are. While humans usually only vacuum once or twice a week (if they are eager), your robot can be set to do daily cleans while you're out of the house.
You'll probably want to be there while it cleans, however, at least for the first few runs, just to make sure it doesn't tangle itself on a phone charger or knock something delicate over.
If the battery is low, most new devices will automatically return to the charging station. Once recharged, some of them even continue vacuuming exactly in the spot where they left off. This is only relevant for homes with a large surface area on one floor, and the battery will likely easily manage one or even two sweeps of a smaller apartment.
You also shouldn't expect them to be zero-maintenance, quite like cordless vacuums, and in most models, you'll regularly need to empty out the dust tray, as well as wipe dust off the sensors and clean the filter.
Robots have also long made their appearance as a garden helper. Different from robot vacuums, robotic lawn mowers neither use lasers nor camera but collision sensors.
"As a rule, they choose their paths randomly and change direction when they bump into something. Ultrasound is also used in some cases," Kliem said.
High-priced models are equipped with a GPS system to make them easier to find on large properties and protect them from theft.
According to Stiftung Warentest, the lawn area should be at least 100 square meters (1,076 square feet) to make the purchase worthwhile. The robotic mower also prefers level ground and at most slight inclines to work well.
Another perk is that robotic mowers never need to be emptied. They only cut short pieces off the blades and drop the grass clippings as fertilizer. Mulching prevents the lawn from forming moss and becoming matted.