Robot Vacuums: What the Specs Actually Mean

Robot vacuums are sold on one number - suction in pascals - and it explains less about living with one than the rest of the spec sheet does. What actually varies between tiers is how the robot sees obstacles, what it does with the mop on carpet, and how high an edge it can climb. This guide explains what each published spec physically changes, then compares three models side by side.

Suction in pascals scales, but not linearly with results

The three models here publish 6,000 Pa, 13,000 Pa and 22,000 Pa. That is a genuine range rather than marketing noise, but pascals measure static airflow pressure at the nozzle, not debris pickup, and the relationship between the two flattens quickly on hard floors. Fine dust and crumbs on tile or wood come up at the bottom of this range.

The extra pressure earns its place on carpet, and specifically deep pile, where debris has to come up through fibres rather than off a flat surface. If your floors are hard throughout, suction is the spec you can most safely stop optimising.

Worth knowing: each manufacturer measures pascals under its own conditions, with no shared industry test, so cross-brand comparisons are approximate.

Obstacle avoidance is what decides whether you tidy first

This is the spec that separates the tiers most sharply, and it is not a number. The budget model here navigates with LiDAR mapping and cliff sensors but no camera - it maps the room accurately and still cannot identify what a charging cable is. In practice that means a pre-clean pass by you: cords, socks, pet bowls off the floor.

Camera-based systems change that. The mid-tier model publishes an RGB camera with 3D structured light and an LED for dark rooms; the premium one adds a stated recognition set of 108 object types on a LiDAR turret that retracts, which is what lets a taller sensor stack fit under a sofa.

No tier eliminates floor prep. The spec tells you how much of it you still do.

Mop lifting and washing is the specification most worth reading

Two mechanisms hide behind the word “mop”. The first is lifting: whether the robot raises the pad on carpet, and by how much. Published figures here run from no lift at all - the pad is detachable and you remove it yourself - to 10.5 mm, to a chassis lift of up to 17 mm. Where a rug sits in a hard-floor room, that is the difference between one pass and two.

The second is what the dock does with the dirty pad. The two higher tiers publish hot-water washing at 158°F and 176°F, with warm-air drying at a stated 113°F on the premium model. Drying matters more than temperature: a pad left damp in a closed dock is the usual source of the smell owners describe.

Threshold clearance is a yes-or-no spec

Published climbing heights here are 20 mm, 22 mm and a stated 1.57 inches for double-layer thresholds. Unlike suction, this one has a hard edge - either the robot gets over the strip between your kitchen and hallway or it does not, and a room it cannot enter is a room it never cleans.

Measure the tallest threshold on the robot’s route before comparing anything else - it is the fastest way to rule options out.

Matching the specs to your floors

Rather than a single answer, the useful question is which constraint binds hardest in your home.

• Mostly hard floors, simple layout - suction is the least binding spec here; threshold clearance and dock capacity matter more.
• Deep-pile carpet or rugs - suction and mop lift height together, since one handles pickup and the other prevents a wet rug.
• Cluttered floors, cables, or pets - obstacle avoidance, because that is the spec that decides how much you tidy before each run.
• Raised thresholds, or low furniture to clean under - climbing height and robot height, measured against your own door strips and clearances.
• You want to think about it as rarely as possible - auto-empty capacity and the stated days between bag changes.

The spec table below carries the published figures for each of these axes.

Frequently asked questions

Do robot vacuums work well on both carpet and hardwood?

Hardwood is the easier surface and every tier handles it. Carpet is where the published suction figure starts to matter, and high pile reduces effectiveness across all tiers. With deep pile, read the suction spec and the mop-lift height together - a robot that mops without lifting will wet the carpet it crosses.

How much maintenance do robot vacuums actually require?

Expect to clear hair from the brush roll and replace filters and bags on the manufacturer’s schedule. The published auto-empty figures - 90 days, 75 days and up to 7 weeks here - describe bag changes under each maker’s stated conditions, not how often the robot needs attention.

Will a robot vacuum work in a multi-level home?

None of them climb stairs, so you either carry the robot between floors or use one per level. Mapping-based models generally let you save a separate map per floor, which makes moving one between levels workable - though the dock stays where it is, so only one floor gets automatic emptying.