What is a Robot Lawn Mower and How Does it Work?

close-up of a black and orange robotic lawn mower sitting on grass

A robot lawn mower cuts the grass in your yard much like a robot vacuum sucks up dirt and crumbs in your house. But what is a robot lawn mower and how does a robot mower work? We’ll answer those questions in this article and throw in a brief history of robot lawn mowers, too. 

What is a robot lawn mower? 

These autonomous roving mowers use cutting-edge technology to keep your lawn consistently trimmed with almost no effort on your part. By cutting just a few millimeters of grass off the top every day, your lawn stays sharply manicured without noticeable streaks.

The second-most common type of domestic robot (after the robotic vacuum cleaner), mowing robots are more advanced and more affordable than ever. And these little gizmos are a big business – the U.S. robotic lawn mower market is expected to reach $704.5 million by 2027, according to a market forecast from Arizton.

Why are sales of robot lawn mowers booming? Mowing the lawn is a chore many of us would rather not do. It’s hot, it’s sweaty, it’s loud, and it takes up valuable weekend time.

How does a robot lawn mower work?

How do robot lawn mowers work? Do robotic lawn mowers really eliminate all your mowing chores? Are they safe? You may have a lot of questions about modern robots and their potential impact on your life. 

We’ve got the answers to your questions.

Except for the installation period, owning a lawn-mowing robot is a hands-off task. Though you may need to break out the weed eater now and then to trim your edges, a robot can eliminate mowing altogether when operated according to manufacturer instructions.

So how does a robot lawn mower actually work? These key components help these self-guided mowers to give your yard a consistent, even cut:

  • Charging dock
  • Boundary and guide wires
  • Cutting route (random or pattern)
  • Safety and anti-theft features (because these little robot mowers are big ticket items)
  • Other special features (LED lights to mow while you sleep)

Let’s take a close look at the home base, basic installation, grass-cutting routing system (or lack thereof), and the other features of robot lawn mowers:

Home base: The charging dock

The vast majority of robot mowers today draw power from your home. A docking station near an outdoor outlet provides all the juice your robot needs, as well as an out-of-the-way spot to recharge between mows.

The robots are designed to return to their base station automatically when they need to recharge, or when their pre-programmed mowing period ends. Some models use a radio frequency to find their dock, while others use a guidewire.

Most mowers recharge in under two hours. If the programmed mowing period is still active when charging finishes, it can head right back out into the field. 

Bonus Points for Flexibility: The Worx Landroid series of mowers features a removable battery that is compatible with other tools. You can instantly recharge a Landroid if you have a spare battery on hand. 

Bonus Points for Green Living: Like all electric mowers, these robots have no emissions and can greatly reduce your carbon footprint.

Installation: Boundary and guide wires

How does a robotic mower know where to go? How does it know where not to go? 

Generally, a boundary wire is laid around the perimeter of your yard and no-mow spots like mulched areas and flower beds. This wire can be buried about an inch below the surface of your yard or adhered discreetly to the ground with lawn staples.

The boundary wire carries a low-voltage electrical current that the mower senses and responds to. 

The wires, even the above-ground variety, are low-voltage and perfectly harmless to touch. 

Installation is often available: Because wire installation is the most complicated step in owning a robotic mower, some vendors and dealers will offer professional installation. For instance, the Honda Miimow is only available through licensed Honda dealers, and they handle all installation and maintenance.

Bonus Features: Some mowers, such as the Husqvarna Automower series, come with additional guidewires laid throughout the lawn that can act as recharging routes and remote start points. 

For example, if you have a narrow passage between garden beds that separates two mowable areas, laying a wire through that passage and creating a remote start point will ensure that area isn’t neglected.

Cutting route (random or pattern)

The actual cutting action varies from robot mower to robot mower. 

Random cutting: The most common cutting pattern is random: that is to say, the mower roams your yard daily, cutting just a tiny bit of grass off the top. 

An intelligent program makes sure that all areas of the yard receive the same amount of attention. The cuts are so frequent and so small that even “missed spots” appear consistent with the freshly mown sections.

Pattern cutting routes: Some mowers have cutting patterns. The Honda Miimow, for example, can cut in a back-and-forth striped pattern across the whole yard. 

Mowers like the Husqvarna 450XH have an automatically-triggered “spiral cut” pattern. When thicker or slightly overgrown grass is detected, the mower begins to spiral out from that point, making sure that all the surrounding area is mown evenly.

Cutting a tiny bit of grass more often comes with another distinct advantage. Robotic mowers are, by their very nature, mulching mowers. The tiny grass tips are sliced into fine powder by the high-speed razor-like cutting blades and distributed back into the soil. This feeds your lawn to keep it greener and healthier.


Operating your robot lawn mower couldn’t be simpler. Many mowers on the market today have a mobile phone app that allows you to access your mower via Bluetooth, Wi-Fi, or cellular data. 

How easy is it to operate a robot mower? Just choose:

  • Mowing time: You can set your mower to run only at night
  • Where to start: You can choose a remote starting location. 
  • Find your mower: Data-enabled mowers can be precisely located. 

Mowers without apps are controlled with an onboard interface. Most of these are quite simple and intuitive.

Safety and anti-theft features

If you have children or pets, the idea of an autonomous machine with rapidly rotating razor blades may be a cause for concern. Not to worry. 

Shut-off sensors

Modern robot mowers are equipped with shut-off sensors that instantly stop the blades when the machine is tilted or lifted. Some models have sensors that stop the blades if a foreign object passes under the edge of the mower. Some have wide guards that keep the blades far from the edge.

Lift alarms, device locks, and GPS 

Worried your robot mower will be stolen? Most manufacturers have considered this. 

Loud lift alarms are the go-to deterrent. Many mowers will need to be unlocked with a PIN code before they work after being lifted or crossing their perimeter line. Some mowers will only work with a special radio signal that links them to their charging station.

Robot lawn mowers that have GPS capability can be tracked via the app, and send you notifications that let you know they’ve been taken.

Other special features

A lot of mowers come with extra bells and whistles to set them apart from the competition. 

Lights: LED headlights can help you keep track of your mower at night

Alexa, mow my lawn: Some robot mowers can interface with smart home systems, like Google Home or Amazon Alexa.

Rain sensors: While these outdoor robots are universally designed to be rain-resistant, some homeowners prefer not to mow wet grass. The solution to this problem is a rain sensor included with many mowing robots. 

The robot can automatically return to its home base when it senses excess moisture. This feature protects your grass, and also prevents your robot from getting stuck in a puddle.

Some mowers have unique blade decks:

Husqvarna robot mowers feature a “floating deck” to improve its height accuracy on bumpy terrain. The cutting height is set digitally and maintains an exact distance from the ground, rather than a fixed height relative to the wheels. 

The McCulloch ROB mower has a pivoting cutting disk that gives way when a solid object is encountered. This helps prevent broken blades and flying debris. 

WORX robots feature an offset cutting disk that hugs one side of the body. This allows it to cut much closer to walls, fences, and the boundary wire, reducing or eliminating the need for a weed eater.

A brief history of the robot lawn mower

So, when did the first robot lawn mower roll across a lawn?

1969: The first lawn robot was developed in 1969. The original MowBot pioneered many of the features still common in today’s robots. 

Five sensors on the bottom were designed to redistribute wheel power when a powered boundary line was detected.The Mowbot cu grass in an entirely random pattern, so a remote control allowed the operator to maneuver through narrow spaces and address missed spots.

1990s: The 1990s introduced the concept of solar power to the lawn robot market. Solar bots promised to be entirely self-sufficient, but never really took off commercially. Some models are still available, though they are few and far between.

2019: In 2019, companies like Toadi began developing camera-driven mowers, able to distinguish their boundaries visually. 

2020: In 2020, Husqvarna and Segway introduced mowers that determine their boundaries via GPS location. Though this technology isn’t yet industry-standard, it’s exciting to see where robotic mowing is headed in the near future.

2021: In 2021, the Bosch Indego developed the key to modern robotic mowing. An onboard intelligence kept a virtual map of the yard and redirected the mower as needed, ensuring no more missed spots.

Mixing old and new tech: Though they’re far more advanced than the original, today’s robotic lawn mowers work the same way. A perimeter wire keeps the mower within its boundaries, and the remote control system has been replaced with additional guide wires for autonomous navigation. 

Some supplement their lawn mapping capabilities with onboard GPS technology. Smartphone apps have made adjusting and reprogramming the bots easier than ever.

The future of robotic lawn mowers is ever-changing. Developers are eager to do away with the ground wire altogether to cut down on installation and increase adaptability. 

Robotic lawn mowers: Pros and cons

You may be asking yourself whether or not these machines are truly an adequate replacement for your trusty gas mower. Well, there are pros and cons to both. 


  • Robot does the work: You don’t. You can sit back and watch your robot mow, mow, mow your lawn – or set it to cut your grass while you sleep.
  • Quiet: Robot mowers operate at a whisper instead of a roar. Your robot mower’s noise won’t anger your neigbors – even at night.
  • Mow anytime: Day or night, you can cut your grass. You can literally set it and forget it. 
  • Lower maintenance: Electric-powered mowers, like robots, are lower maintenance.
  • Eco-friendly:  Robot lawn mowers have drastically lower environmental impact than gas machines. 


  • Expensive: Robotic mowers are expensive and can be well out of budget when extra features are considered. 
  • May need installation help: Those averse to laying ground wire may need to shell out some cash for a professional installation. 
  • Best for smaller yards: People with larger yards may have a tough time finding a robomower that works for them. Mid-range robots usually cover around half an acre, with larger areas adding considerably to the price tag. 
  • Just mowing: If you like to have all your mowing, edging, and weeding done at once, a robot isn’t the answer.
  • Not meticulous: If you are meticulous in your lawn care efforts, a robotic mower probably won’t give you what you’re looking for. They rely on routine and randomness to produce a consistent, streak-free lawn.
  • Thieves like robo-mowers: Homeowners in neighborhoods with high theft rates will want to pay extra for GPS tracking and anti-theft features. 

The biggest advantage of a robot lawn mower over a classic push or ride-on lawn mower? The chore of mowing the lawn is all but eliminated. You may need to keep an eye on your edges and touch up here and there with a string trimmer, but you’ll spend a lot less time thinking about the state of your lawn.

Lawns are often healthier under the care of a robotic mower, as their mulching capabilities result in well-fed, lush growth

Robots are much quieter than traditional lawn mowers, with some models like the Gardena Sileno producing only 56 Db of noise. That’s quieter than a standard air conditioning unit. Quiet mowing means your lawn mower can run at night without disturbing your sleeping neighbors, leaving your yard open for use during the day.

Whether or not domestic robots are truly the future of chores remains to be seen. As autonomous technology improves, so will the capabilities of robotic helpers.

When to call a lawn care pro

If you’re still not sold on the idea of robots, you can still take the hassle out of maintaining a beautiful lawn. Lawn Love pros are always on-call to deliver gorgeously manicured lawns at affordable prices. Until there’s a robot built for tree-trimming, leaf-raking, or weed control, nothing can beat a professional touch.

Main Photo Credit: distelAPPArath | Pixabay

Stephen Kime

Stephen Kime is a freelance writer and professional actor based in Washington, D.C. When he isn't in rehearsal, Stephen enjoys running, hiking, and experimenting with new cocktail recipes.