Xiaomi S40 Pro: extending mop, 10 mm lift, 15,000 Pa

Dual extendable arms at the skirting

Most robots leave a thin line of dust along the skirting because the round body cannot get flush to the wall. Xiaomi's answer is to push both the mop and the side brushes outward as the robot follows an edge, adjusting their reach so they sit as close as 1 mm from the wall. The listing also mentions reaching under furniture, which helps around kitchen plinths and bed frames.

Obstacle sensing is described as wide-angle, and the robot navigates by LiDAR, with schedules, modes and room control in the Mi Home app plus Google Assistant and Alexa voice commands.

Hair handling and carpets

The main brush and side brushes both have Y-shaped combs and anti-tangle structures, and the listing names long hair and pet fur as the target. That is a useful detail for anyone used to cutting hair off a brush every week, although Xiaomi does not quote a maximum hair length.

Ultrasonic sensors detect carpet, raise the mop by 10 mm and turn up suction, so you can leave the mop fitted on a home with a few low rugs. Deep-pile rugs are not covered by the listing, so treat them with care.

Battery, bin and water tank

The 5,200 mAh battery is rated to clean up to 180 m² on one charge, which covers most flats and many family homes. The spec table separately lists 120 minutes of battery life. On board there is a 430 ml dustbin and a 310 ml water tank. Because no self-emptying station or mop washing dock is listed, you will empty the bin and rinse the mop pad by hand, and how finely water flow can be set is not described.

Compared with the X20 Pro and eufy C28

The Xiaomi X20 Pro gives up suction, at 7,000 Pa, but adds a base that empties dust for 75 days and washes and hot-air dries the pads. The eufy Omni C28 matches the S40 Pro's 15,000 Pa and adds a full station and DuoSpiral brushes rated for 30 cm hair. The S40 Pro wins on edge reach and on how little floor space it needs.