Robot Vacuum Features Explained: Lidar, Self-Empty Bases, Mopping and What Actually Matters

Robot vacuum spec sheets are a wall of acronyms and large numbers. Most of them matter less than two questions: can the robot reliably map and cover your home, and will it stay out of trouble (cables, rugs, pet accidents) while you are away? This guide explains each feature, what it is actually for, and when it is worth paying for.

Navigation: the feature that matters most

• Bump-and-go (random): no map; cheap; misses spots and gets stuck more. Fine for a single small room.
• Gyroscope/optical: tidy rows, basic maps that may reset; good value for simple layouts.
• Camera (vSLAM): maps from ceiling features; struggles in the dark unless it has a light.
• Lidar: a spinning laser builds an accurate map in any lighting, enabling room-by-room cleaning, no-go zones and faster coverage. The most dependable option for multi-room homes.

Obstacle avoidance

Front cameras or structured-light sensors let newer robots steer around cables, socks and pet waste. This is the feature that decides whether you can run the robot unattended. Cheaper robots rely on bumpers and will drag cables; keep floors clear or budget for avoidance.

Suction and 'Pa' numbers

Suction is quoted in pascals (Pa). Higher helps on carpet, but brush design, airflow and seal matter as much; a 2,500 Pa robot with a good brush roll can out-clean a 5,000 Pa robot on hard floors. Treat Pa as a rough tier indicator, not a ranking. Look for carpet boost (automatic suction increase) if you have rugs.

Self-empty bases

A base with a vacuum bag empties the robot's small bin after each run, typically holding 30–60 days of debris. It is the single biggest convenience upgrade for pet owners and daily cleaning, at the cost of bag purchases and base noise for about 10–20 seconds.

Mopping

• Drag-pad: a damp pad wiped along the floor; removes dust film, not stains.
• Vibrating/oscillating pad: better on light grime.
• Rotating pads with lift: closest to a real mop and can raise over carpet.
• Self-wash and dry stations: refill and clean the pads automatically; the most expensive tier.

Other terms

• Runtime: 90–180 minutes is typical; most robots recharge and resume mid-job.
• Threshold height: how tall a rug edge or door sill it can climb, usually 15–20 mm.
• Height: a robot under about 8 cm fits under more furniture.
• HEPA filter: useful for allergy households; check replacement price.

Top picks by use case

Specific model recommendations for this section are being checked against current retailer prices and availability, and will appear here once verified.

Glossary

• SLAM — simultaneous localisation and mapping; the method the robot uses to know where it is.
• No-go zone — an area you draw on the map that the robot avoids.
• Carpet boost — automatic suction increase on carpet.
• Edge cleaning — a final pass along walls.