Robot Vacuum Glossary

Last updated: March 2026 · 8 min read

Robot vacuum spec sheets are full of jargon. This glossary defines every term you'll encounter — in plain language, with enough context to understand why each feature matters.

Auto-Empty Dock: A docking station that automatically suctions debris from the robot's onboard dustbin into a sealed bag or container in the base. Most bags last 60 to 150 days before needing replacement. This is the single feature that turns a robot vacuum from a daily chore into a set-and-forget appliance.

Brush Roll: The spinning cylindrical brush on the underside of the robot that agitates debris off the floor and feeds it into the suction path. Designs vary — rubber finned rolls resist hair tangles better than bristle brushes, and some models use dual counter-rotating rolls for improved pickup on carpet.

Carpet Boost: An automatic feature that increases suction power when the robot detects carpet. The robot uses sensors (typically ultrasonic) to identify the surface change and ramps up the motor accordingly, then returns to normal suction on hard floors to conserve battery.
Carpet Detection: The sensor system that identifies when the robot has moved from hard floor onto carpet. Most models use ultrasonic sensors that emit a sound pulse and measure how the surface absorbs it. Carpet detection is what enables carpet boost and, on mopping robots, automatic mop lifting to avoid wetting the carpet.

DToF (Direct Time of Flight): A LiDAR measurement method that calculates distance by timing how long a laser pulse takes to travel to a surface and return. DToF sensors are more accurate at longer ranges than indirect ToF alternatives and have become the standard in premium robot vacuum LiDAR systems. Sometimes also written as dToF.
Dual Spinning Mop: A mopping design that uses two round microfiber pads rotating simultaneously, typically at 180 to 200 RPM. The dual-pad configuration provides wider coverage and more consistent downward pressure than single-pad designs. This is the most common mopping system across mid-range and premium robots.

Edge Mopping: A feature that allows the robot to clean along baseboards and wall edges more effectively. Standard round robots leave a gap of 1 to 2 centimeters along walls. Edge mopping systems — such as Roborock's MopExtend or Dreame's FlexiArm — extend a mop pad beyond the robot's body to close this gap.

FlexiArm: Dreame's branded edge-cleaning mechanism. A side mop arm extends outward from the robot body to reach along walls, under furniture edges, and into corners that the main mop pads cannot access. Similar in function to Roborock's MopExtend, though the mechanical implementation differs between brands.

HEPA Filter: High Efficiency Particulate Air filter — a filtration standard that captures at least 99.97% of particles 0.3 microns or larger. In robot vacuums, HEPA-rated filters trap fine dust, allergens, and pet dander that would otherwise be recirculated into the room air. Particularly important for allergy sufferers. Note that some manufacturers claim "HEPA-style" or "HEPA-like" filtration without meeting the true standard.
Hot Water Wash: A dock feature that heats the mop-washing water to at least 149 degrees Fahrenheit (65 degrees Celsius). Hot water dissolves oils and greasy residue far more effectively than cold water and helps kill bacteria on the mop pads. Combined with hot-air drying, it prevents the sour smell that was common with earlier-generation mop docks.

LDS (Laser Distance Sensor): Another name for the LiDAR sensor module used in robot vacuums. LDS is a term you'll see in some manufacturers' spec sheets — particularly Roborock and Xiaomi — and refers to the same time-of-flight laser scanning technology as LiDAR. The terms are interchangeable in this context.
LiDAR: Light Detection and Ranging. A sensor that fires rapid infrared laser pulses while spinning, measuring how long each reflection takes to return. This produces an accurate 2D map of the room in real time. LiDAR is the dominant navigation technology in robot vacuums from about $300 upward and enables features like multi-floor mapping, room segmentation, and efficient row-by-row cleaning paths. See our technology explainer for a deeper dive.

Mapping: The process by which a robot vacuum creates and stores a floor plan of your home. LiDAR-based mapping is the most accurate method. Once mapped, the robot uses the stored plan to navigate efficiently, clean specific rooms on demand, and avoid re-mapping on subsequent runs.
Matter: An open smart-home connectivity protocol backed by Apple, Google, Amazon, and Samsung, among others. A robot vacuum with Matter support can integrate natively with Apple Home, Google Home, and Alexa without needing a brand-specific hub or skill. Adoption is still limited — the Ecovacs X9 Pro Omni is one of the few robot vacuums with full Matter compatibility as of 2025.
MopExtend: Roborock's edge-mopping technology. A mop pad mounted on an extendable arm swings outward beyond the robot's circular body during cleaning to reach along walls and into corners. This closes the gap that standard round robots leave along baseboards, typically improving wall-edge coverage from about 1.5 cm to under 2 mm.
Multi-Floor Mapping: The ability to save and recall separate maps for different stories of a home. When the robot is carried to another floor, it recognizes the environment and loads the correct saved map. Most models support 3 to 5 stored maps, which is sufficient for a typical multi-story house.

No-Go Zones: Virtual boundaries drawn in the robot's app that tell it to avoid specific areas. You might set no-go zones around pet bowls, delicate furniture legs, or areas with lots of cables. The robot treats these zones as invisible walls and routes around them. Most apps also support no-mop zones, where the robot will vacuum but skip mopping.

OZMO: Ecovacs' branding for its mopping technology platform. The standard OZMO system uses oscillating or vibrating pads. The more advanced OZMO Roller replaces pads with a continuously rotating cylinder that self-washes in real time during cleaning, achieving the highest mopping scores ever recorded in independent testing (4.95/5 by Vacuum Wars).

Pa (Pascals): The unit used to measure a robot vacuum's static suction pressure. Higher Pa values indicate a stronger motor, but Pa alone does not predict cleaning performance — airflow design and sealed suction (measured in kPa) matter equally. Current models range from about 4,000Pa on budget robots to 25,000Pa on flagships. For context, 8,000Pa is adequate for hard floors, while 12,000Pa or more is preferable for carpet. See suction power demystified for a full explanation.
ProLeap: Dreame's obstacle-climbing technology, previewed on concept models. Small retractable legs deploy from the robot's underside to physically lift it over thresholds, raised transitions, and obstacles up to about 4 cm (1.6 inches) tall — roughly double what conventional wheels can manage. Still in early stages of commercial availability.

RGB Camera: A standard color camera mounted on the front of the robot, paired with an AI model trained to recognize specific objects. Unlike structured light or infrared sensors that only detect shapes, the RGB camera can identify what an obstacle is — a shoe, a cable, a pet accident — and the robot adjusts its behavior accordingly. This is the technology behind object-specific avoidance in premium models.
Room Segmentation: The ability for the robot (or the user, via the app) to divide a mapped floor plan into individual rooms. Once segmented, you can send the robot to clean specific rooms, set per-room suction and mop settings, and schedule room-by-room cleaning routines. Most LiDAR-equipped robots auto-detect room boundaries and let you adjust them manually.

Sealed Suction: A measurement of suction performance taken with a calibrated gauge over the robot's actual intake, accounting for the complete air pathway including filter and dustbin. Measured in kPa, sealed suction is a more accurate predictor of real-world cleaning performance than the raw Pa rating. For example, the Ecovacs X9 Pro Omni measured 2.76 kPa of sealed suction — the highest among 2025 flagships — despite not having the highest Pa rating.
Self-Wash Dock: A docking station that automatically washes the robot's mop pads after each cleaning session (or mid-session on some models). Premium docks wash with hot water, apply detergent, scrub the pads, and then dry them with hot air. This is essential for maintaining hygiene and preventing odor on mop-equipped robots.
Structured Light (3D): An obstacle detection technology that projects a grid of infrared dots in front of the robot. A camera reads how the dot pattern deforms around objects, revealing their 3D shape and distance. It works in complete darkness and detects objects a few centimeters tall, making it the standard mid-range obstacle avoidance sensor. Its main limitation is that it sees shapes but cannot identify what an object is — that requires an RGB camera.

Turret (LiDAR): The raised dome on top of a robot vacuum that houses the spinning LiDAR sensor. The turret needs to protrude above the robot body to get an unobstructed 360-degree view, which adds to the overall height. Some manufacturers have developed retractable or low-profile turret designs to reduce the robot's total height — the Roborock Qrevo CurvX at 3.14 inches is a notable example — allowing the robot to fit under more furniture.

Virtual Walls: Software-defined boundaries set in the robot's app that the robot treats as physical walls. Similar to no-go zones but typically drawn as a line rather than an area. Useful for blocking doorways, hallways, or open floor plans without physically moving furniture. Some older models used physical infrared beacons to create virtual walls, but app-based digital walls have largely replaced them.

Zone Cleaning: An app feature that lets you draw a custom rectangle on the map and send the robot to clean only that area. Useful for spot-cleaning around a dining table after a meal or targeting a specific high-traffic zone without running a full-home session. Most models allow you to set the number of cleaning passes per zone.

Go Deeper

Want to understand the engineering behind these features? Read our technology deep dive. Ready to choose a model? See the buying guide or our top picks.

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