Robot lawnmowers have come a long way in the last 18 months. The latest models are smarter, more capable, and far less likely to get stuck or lost. But they are still not set-and-forget machines. If you don't want them to tear up your lawn or wander into a neighbor's yard, you still need to keep an eye on them. With some oversight, though, they can take a big chore off your hands.

I tested five robot mowers on my flat, three-quarter-acre property in coastal South Carolina, which has sandy soil, centipede grass, and lots of trees. The results were encouraging. The best mower never got stuck once, handled uneven terrain with ease, and mowed my entire yard in record time. Others struggled in soft ground, had trouble with obstacles, or relied too heavily on cloud services.

Key upgrades in today's robot mowers

The biggest improvements are in navigation. Most high-end models now use RTK (real-time kinematic positioning) satellite technology, which provides centimeter-level accuracy. Instead of burying boundary wires, you install a small antenna in your yard with a clear view of the sky. Many models now also support NetRTK, which uses cellular networks to access a network of reference stations, eliminating the need for a physical antenna in many cases.

In addition to RTK, many mowers now have fallback navigation systems such as lidar, vSLAM, or camera-based vision. These help the mower stay on track when the satellite signal drops, especially near trees or buildings. This combination of technologies was a game-changer. In my previous testing, not a single RTK mower could work in my backyard due to spotty GPS coverage. This year, all of them managed to navigate the area without constant human rescue.

Another major upgrade is all-wheel drive. Bigger, beefier mowers with AWD and improved suspension can handle potholes, roots, and small branches. They can also climb slopes up to 80 percent, making them suitable for more challenging landscapes.

What still needs work

Despite the improvements, robot mowers are far from perfect. These are autonomous machines with blades, and leaving them to their own devices comes with risks. During my testing, one mower spent three days methodically destroying a patch of lawn before I noticed. Another took out two outdoor extension cords. Several models dug sandpits in bare spots, and one tried to climb up a small tree.

Obstacle detection is better across the board, but it still has a long way to go. Hoses, cables, and cars remain problematic. My family now knows to check under the wheels before driving away. Even the best mowers can't reliably see all obstacles, so you need to clear your yard of potential hazards before each mowing session.

Gates are another unsolved problem. No manufacturer has really solved automated gate crossing yet. I still have to manually open my gate to let the mower reach the front yard. Some mowers try to handle it by using network RTK and having the mower continue along a path, but it's not seamless.

There are also concerns about cloud dependence. While every manufacturer currently advertises NetRTK coverage as free for the lifetime of the device, relying on a cloud service to mow your lawn is a potential risk. If the company goes out of business or changes its policy, your mower could lose a critical navigation layer.

The robot I'd get for my yard

Segway Navimow X430

The Segway Navimow X430 is the best robot lawnmower I tested. This 60-pound machine looks like Darth Vader's dog, and it was the only mower that didn't get stuck once. Its 4WD wheels with impressive suspension rolled through potholes, over sticks and rocks, and even across small tree branches. It navigated around my chickens and easily handled the tall, uneven transition from the front yard to the back. It was the only bot that could mow both areas in one trip, as long as the gate was open.

The X430 uses RTK, vSLAM, and vision-based technology to navigate. It covered my entire property without once getting lost or stuck. Its xero-turn maneuverability lets it pivot smoothly without damaging the lawn, and its dual-disc, 17-inch cutting width covers more ground than most competitors. It mowed most of my backyard in under three hours, which was nearly twice as fast as the other mowers I tested.

I particularly liked the remote-control mowing feature. It was handy for tidying up edges and sensitive areas around flower beds. The Segway's speed does mean a few blades go untrimmed, and its rain sensing relies on weather data from the internet, which meant it often skipped mowing because it predicted rain that never came. Setting up NetRTK was a bit tricky because the charging station had to be placed with a clear view of the sky, but once configured, it worked flawlessly.

A good lidar-based alternative

Dreame A3 AWD Pro 2500

The Dreame A3 AWD Pro 2500 is the best option if you can't rely on RTK. Its lidar and camera-based navigation performed nearly as well as the Segway in my backyard, only getting stuck a couple of times. It doesn't need a clear view of the sky, so you can place the charging station anywhere. Its sliding edge-cutting deck also worked slightly better than the Segway's EdgeSense feature.

However, lidar was the least reliable navigation technology in my testing. Sometimes the A3 declared the job complete when it wasn't, and lidar robots can get lost and wander into neighboring yards. They do best in fenced-in yards. The Dreame rarely got stuck, but its turning mechanism wasn't as smooth as the Segway's, and it dug several sandpits in areas with no grass. I did like its Garden Guardian mode, which uses the camera as a roaming security guard and can warn people when they cross its path. It was mildly hilarious watching it surprise dog walkers passing by the front yard.

An expensive but reliable option for yards with no trees

Husqvarna Automower 420 IQ

Husqvarna's Automower 420 IQ is a good option for a standard, open yard. It has the longest warranty of the group at four years, the easiest app and controls, and a modular design for longevity. It's 2WD, but its large wheels tackle uneven terrain well. The 420 IQ requires an RTK antenna and has the option of cloud-based RTK in some areas. For backup navigation in satellite dead spots, it relies on physical boundary wire, which is a step backward compared to most competitors.

I tested this mower in my neighbor's yard because their property has fewer trees and clearer views of the sky. It navigated well, but it uses radar for obstacle detection and has no camera at all. This meant it wasn't as good at dodging objects as the others. It ran into bushes once and tried to climb a small tree. But if you have a large, uncomplicated, tree-free yard, the Husqvarna is a solid choice thanks to its broad support network, free-for-life cellular connectivity, and impressive performance.

More reliable navigation, but spotty software

Mammotion Luba 3 AWD 3000

The Mammotion Luba 3 AWD 3000 combines all three wireless navigation types: RTK, lidar, and vision. This makes it ideal for properties with spotty GPS coverage like mine. However, it's less nimble than the other AWD models due to lower ground clearance and weaker suspension. Its turning mechanism also tore up a couple of areas in my garden, particularly a shaded, damp spot near the neighbors' sprinklers.

Mammotion acknowledged the issue, saying a recent update to the turning logic caused unwanted results, especially when the ground was wet or the grass wasn't thick. They deployed several software updates to address the problem, but it's a reminder that buying an expensive lawnmower and relying on software updates to fix fundamental issues is risky.

A budget option for smaller yards

Roborock RockNeo Q110H

The Roborock RockNeo Q110H is my budget pick. This rear-wheel-drive mower impressed me on my flat, treed front yard, though its lack of AWD meant that large tree roots could stop it in its tracks. That, along with its more limited range, is why it costs about half as much as the other mowers here. It offers RTK and vSLAM navigation, with the option of using an antenna or NetRTK.

The RockNeo is remarkably similar to the Segway Navimow i100N I tested last year, with a few upgrades including better camera-based obstacle detection, steeper slope navigation up to 45 percent, and a wider cutting blade. It can also be used for manual remote-control mowing and has a built-in edge-cutting feature. There's an optional edge-cutting add-on module, though I haven't tried it.

Edge cutting is still a work in progress across all robot mowers. Some do well straddling the edge, but if you have a fence or delicate boundary, that won't work. Companies are trying various solutions, including special attachments. Ecovacs' Goat A3000 Pro Lidar looks promising thanks to a side-mounted string trimmer, but for now, you should plan to keep your manual trimmer handy.

Robot mowers have improved significantly over the last 18 months. Advances in navigation have solved my main pain points from previous testing, and bigger, more capable machines are now better at handling varied American yards. Today, the right bot will maintain your yard beautifully with minimal effort. While they still need oversight and occasional rescue, and they haven't solved every problem, they do take a lot of the work out of maintaining your yard.

Source:The Verge News