Mopping robot vacuums: vibrating plate, spinning pads or roller?

Four kinds of mop

A drag cloth. The simplest form: a damp cloth under the robot that drags across the floor. It picks up dust and light dirt. You usually wash the cloth yourself.

A vibrating mop. Roborock calls its system VibraRise: the mop plate vibrates back and forth. Roborock gives 3,000 vibrations per minute for the S7 and 4,000 per minute for the Saros 20 Sonic (VibraRise 5.0), with 14 newtons of pressure.

Two spinning pads. Here two round mop pads rotate under the robot, as with Ecovacs' OZMO Turbo in the T30 family. Xiaomi names "dual rotating mops" for the Robot Vacuum X10+.

A roller mop. A rotating roller that, according to the makers, is kept clean while it mops. Ecovacs describes the OZMO Roller of the X8 PRO OMNI with sixteen nozzles and a scraper; the catalogue has the Ecovacs Deebot X12 OmniCyclone with OZMO Roller 3.0. Eufy calls its roller HydroJet, as on the Eufy C28 Omni and the Eufy S2. The Roborock Qrevo Curv 2 Flow and the Mova Z60 Ultra Roller also have a roller mop according to their names.

Carpet: lift or leave behind

A wet mop doesn't belong on your carpet. Makers solve this in two ways:

• Lifting. The robot detects carpet and lifts the mop. Roborock names up to 5 mm for the S7, Ecovacs 9 mm for the T30 family and Dreame up to 10.5 mm for the X40 Ultra. How thick the carpet may be is a separate figure: Roborock calls the S7's lifting suitable for low-pile carpet up to 4 mm, and Dreame advises setting the X40 Ultra to skip carpet with a pile over 3 mm in the app. The Roborock Qrevo S5V says "Mop lift" in its name, the Roborock Q10 S5+ "Auto Lifting Mopping".
• Leaving it behind or folding it away. Dreame lets the X40 Ultra leave its mops in the station when it goes to vacuum carpet. iRobot folds the mop of the Roomba Combo j9+ all the way onto the top of the robot. On the Dreame Aqua10 Ultra Roller, a cover closes over the roller on carpet.

If you have deep-pile carpet, choose a robot that leaves its mop behind or folds it away, or have it skip those rooms in the app.

The base station

The station decides how much work is left for you.

• Charging or emptying dust only. You wash the mop yourself and refill the water tank in the robot. Robots such as the Dreame D20 Pro Plus have an auto-empty station according to their name.
• Washing and drying the mop. The station washes the mop after mopping and dries it with warm air. Ecovacs names washing with hot water at three levels and drying with 63 °C air for the X8 PRO OMNI. The Ecovacs Deebot T30C Gen 2 names hot water in its name, the Dreame Matrix10 Ultra self-cleaning at 100 °C.
• All-in-one. Emptying dust, refilling clean water and collecting dirty water, often next to washing and drying. Not every station does everything: iRobot names emptying dust for up to 60 days and refilling water for up to 30 days for the Combo j9+ station, but you wash its mop yourself. How often you empty and fill the tanks depends on your home and how often it runs.

Swapping mops per room

Some stations swap mops by themselves. The Dreame Matrix10 Ultra has an automatic mop swap according to its name, so the kitchen can get a different mop from the living room. That is mainly useful if you have different floors or don't want the kitchen mop going through the rest of the house.

What the name says, and the specifications

Many entry-level models only say "with mopping function" in the name, such as the Roborock Q7 M5 and the Roborock Q10 VF+. Then check the specifications for the kind of mop, whether it lifts and what the station does. Suction in pascals (Pa) is in almost every robot's name, but says nothing about mopping. All models are under robot vacuums with mopping; those with a station that empties itself under self-emptying.