Robot Vacuums: How They Work & What to Buy

If pets or kids keep your floors messy, a robot vacuum earns its keep. Here's the engineering behind navigation and suction — plus a live 3D coverage simulator you can tune.

Coverage 0% · Passes 0

Why navigation matters more than suction

The single biggest difference between a cheap and a smart robot vacuum is how it moves. Switch the toggle above from LiDAR to Random and watch coverage crawl — random-bounce models can miss 20–30% of a room even after 45 minutes, while a mapping robot covers it in efficient back-and-forth rows.

LiDAR / VSLAM

A spinning laser (LiDAR) or camera (VSLAM) builds a map, letting the robot clean in straight rows, remember no-go zones, and resume after charging. Best coverage per battery cycle.

Random bounce

Budget robots use bump sensors and turn at a random angle on collision. Cheap and effective for small rooms, but slow and uneven in larger open floor plans.

Suction (Pa)

Measured in pascals: 2,000 Pa handles hard floors and light pet hair; 4,000–8,000 Pa is better for carpet and dense fur. More Pa drains battery faster.

The specs that actually change your life

SpecWhat it doesGood target
SuctionPulls up debris; higher helps carpet & pet hair2,500+ Pa (5,000+ for heavy fur)
BatteryRuntime per charge; bigger homes need more120+ min for 1,500+ sq ft
Bin / dockSelf-empty docks hold 30–60 days of dirtAuto-empty if you hate emptying
Brush typeRubber brushes tangle less with long hairAnti-tangle rubber roller
HeightWhether it fits under your furniture<3.8 in for most sofas

Worked example: time to clean a room

A robot cleaning path length ≈ room area ÷ cleaning-path width. For a 200 sq ft room and a 7-inch (0.58 ft) effective path: 200 ÷ 0.58 ≈ 345 ft of travel. At a typical 1 ft/sec that's about 6 minutes of pure driving — but overlap, edge work, and obstacle detours realistically push a mapping robot to 15–20 minutes, and a random-bounce robot to 30–45 minutes for the same room. That efficiency gap, multiplied across daily runs, is what you're really paying for.

Enjoy this tool? Build your own with Super