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Robot glossary

The words on robot vacuum, mower, pool robot and humanoid spec sheets, in plain language. Each definition links to where we explain it in more depth.

LiDAR: Light detection and ranging. NOAA describes it as using pulsed laser light to measure distances. On robot vacuums, the spinning turret on top that maps your rooms. More
LDS (laser distance sensor): A spinning 2D laser scanner that senses 360° around a robot. Robot vacuum makers use "LDS" and "LiDAR" for the same kind of sensor.
SLAM: Simultaneous localization and mapping: building a map while working out where you are on it. It's how mapping robots clean in rows instead of at random.
vSLAM: SLAM using cameras instead of a laser. It needs light to work well. More
ToF (time of flight): Measuring distance by timing how long light takes to bounce back from an object.
Structured light: Projecting a known pattern of light and measuring how it deforms over objects, to judge their shape and distance. Used for obstacle avoidance.
Cliff sensor: A downward-facing infrared sensor that stops a robot driving off stairs. iRobot says its minimum "cliff" is 3.5 inches (90 mm) and that dark surfaces can sometimes be misread as drops. More
RTK (real-time kinematic) GNSS: Satellite positioning corrected by a nearby fixed reference station, accurate to centimeters. Used by wire-free robot mowers. More
Boundary wire: A perimeter wire, buried or pegged down, that marks where a robot mower may mow and guides it back to its charger. More

Robot vacuum features

Self-emptying dock: A base station that sucks the robot's small bin into a larger bag or bin after each run, so you empty it every few weeks instead of daily. More
Obstacle avoidance: Sensors and software that recognize objects ahead and steer around them, usually a front camera or structured light. Very flat objects remain hard for every system. More
Mop washing: A dock that scrubs the robot's mop pads between or after runs, sometimes with heated water, then dries them with warm air. More

Mowers and pool robots

AWD (all-wheel drive): Drive to every wheel, which lets a mower climb steeper slopes. Husqvarna says its AWD models handle up to 70%, against 25–50% for its standard models. More
Lift and rollover sensors: Sensors that stop a mower's blades when it's picked up or turned over. They're part of the robot mower safety standard's tests. More
Pivoting blades: Small blades that swing back on impact instead of being fixed. In a 2021 hedgehog study, mowers with pivoting blades caused much less damage than fixed blades. More
Suction-side cleaner: A pool cleaner powered by your filter pump's suction through the skimmer or a suction port. More
Pressure-side cleaner and booster pump: A pool cleaner driven by water pushed back into the pool, usually by a dedicated booster pump; it catches debris in its own bag. More
GFCI: Ground-fault circuit interrupter: an outlet or breaker that cuts power if current leaks, for example into water. Maytronics requires one (it calls it an RCD) for its corded pool robots. More

Humanoids and AI

Actuator: Whatever moves a robot's joint: usually an electric motor with a gearbox, sometimes hydraulics or tendons. More
Degrees of freedom (DoF): The number of independent ways a robot can move. The Modern Robotics textbook defines it as the smallest number of coordinates needed to describe the robot's position. A hand with 22 DoF has 22 independently controlled movements.
End effector: The tool or hand at the end of a robot arm. OSHA defines it as an accessory or tool designed to attach to the robot's wrist.
VLA (vision-language-action) model: An AI model that takes camera images and instructions and outputs robot movements. Google DeepMind describes its Gemini Robotics models as converting vision and language input into motor control. More
Humanoid robot: A robot with a roughly human body plan, two arms and usually two legs, built to work in spaces designed for people. More
Preorder vs on sale: A preorder usually means paying a deposit for a robot that hasn't shipped yet. Our tracker only treats a robot as available when ordinary US customers can receive one.
Teleoperation: A human remotely controlling or guiding a robot through its cameras and sensors. More

Software and connectivity

OTA update: Over-the-air: new software delivered to the robot wirelessly. When a maker's servers shut down, updates stop. More
Matter: A smart-home standard that lets devices from different brands work together over your home network. Robot vacuums were added in Matter 1.2 (2023). More
Thread: A low-power mesh network that Matter devices can use alongside Wi-Fi.

Safety and regulation

IEC 60335: The international family of household appliance safety standards. Part 2-2 covers vacuum cleaners, including automatic battery-operated ones; part 2-107 covers robotic lawnmowers. More
UL 3300: A North American safety standard for consumer service, communication, information, education and entertainment robots, added on top of the standard for the robot's main function. More
FCC Covered List: The FCC's list of equipment barred from new FCC approvals on national-security grounds. Since July 2026 it includes foreign-produced advanced robotic devices without a Conditional Approval. More
Li-ion and charge cycles: Lithium-ion batteries power nearly all of these robots, and lose capacity with use and age. Dreame puts typical life at about 300 to 500 charge cycles. More

Spec-sheet numbers

Pa (pascal): The SI unit of pressure. Robot vacuum "suction" in Pa is the maker's own measurement, and there's no shared test method across brands, so compare Pa figures with care. See our methodology.
mAh (milliamp-hour): A measure of battery charge. It depends on voltage, so a higher mAh figure doesn't always mean a bigger battery.
Wh (watt-hour): A measure of battery energy, and the fair way to compare batteries. Roughly, Wh ≈ mAh × volts ÷ 1,000. 1X lists NEO's battery as 842 Wh. More
IP rating: Ingress protection, defined in IEC 60529. The first digit is protection against dust and solids, the second against water; an X means not tested. IPX5 means protection against water jets from any direction; IPX7 means immersion to 1 m for 30 minutes.
Slope percent: Rise over run × 100. A 100% slope is 45°, not vertical. More
Mop lift: How far a robot raises its mop pads on carpet, in millimeters. Higher keeps rugs drier. More

Sources

All sources read October 12, 2026.

Last checked October 12, 2026. See what changed.