The most notable thing I’ve learned about robot lawn mowers: How the lawn mower maps, matters. Originally, these mowers all used buried wire to determine the boundaries that the robots couldn’t cross. Then RTK (which stands for "Real Time Kinematic positioning"—essentially, GPS with some additional localized data) made it possible for people to define the boundary without a wire by simply walking the robot around the perimeter of the yard during setup, as long as the robot was in sight of the RTK tower. Now, Ecovacs has attempted something new with the GOAT GX-600 ($999): The device simply uses LiDAR to figure out where to mow and not mow. (LiDAR is what robot vacuums use.)

The problem is, it doesn’t work. Despite trying the GOAT on multiple different lawn setups,I could never get it to complete even one run. It failed to see the entire lawn, often mowed the same area back and forth many times instead of moving to a new area, ignored boundaries like sidewalks, and refused to cross boundaries it should, like walkways. Additionally, it got stuck so often—even on flat, freshly mowed grass—that it was hard to imagine that you’d ever feel confident enough to let the GOAT work autonomously, which is the whole point of a robot.

At least it's light

This is actually the third iteration of the GOAT, and while the v1 and v2 versions of the GOAT seem to have had more success based on previous reviews, neither appear to be available anymore. To its credit, the GX-600 was the easiest robot lawn mower to put together of any I’ve tested. The entire charging base comes already assembled, as did the robot. There are no additional parts, wires, or RTK towers—you just plug it in and send the robot out to explore your lawn. The base, made of plastic, and the robot were both light enough to move around (which I did a lot of). 

You May Also Like

Troublesome connections

It took a few tries to pair the GOAT with the app, but it was still easy enough to do in under 10 minutes by power cycling the robot. In the case of most lawn mower apps, you can access a lot of settings from the app interface, whether the mower is online or not. In the case of Ecovacs, you can only access these settings while the mower is online. Once it is, you can connect via Bluetooth or wifi, with some operations requiring the Bluetooth. Most operations you set on the robot itself, like setting the height of the lawn. From the app, you can set schedules, and decide to operate the robot in auto mode or manual mode. Manual mode is code for “remote control,” which is a feature easier to find on other apps. I routinely had trouble connecting via Bluetooth to the robot, even when only 10 feet away, and it’s a requirement for the manual mode. I had to use manual mode a lot on the GOAT to try and move it out of an area it was having trouble with, and I struggled to connect and maintain that connection. 

Too picky for its own good

Most robot lawn mowers claim to work on most lawns, inhibited only by square footage and incline. The GOAT, based on the way it maps, is different. Ecovacs has an entire pre-purchase quiz to help you decide if the GOAT is right for you, and there are several parameters that might rule your lawn out. First, your lawn needs to be enclosed, either by a physical boundary like a fence or a sidewalk. Second, it has to be mostly contiguous—it can only be broken up by one walkway less than 1m (three feet) across. Third, any interior “islands,” such as planting beds, raised beds or other obstacles like lawn furniture, must have a physical barrier around them that the robot can sense.

Promised features didn't work

The Ecovacs GOAT insisted on mowing this individual strip over and over, for twenty minutes but never got the rest of the lawn. Credit: Amanda Blum

On the first lawn I tried—which featured large expanse of grass with no islands or any kind, but with an incline, surrounded by fences and sidewalks, and divided by one 24-inch walkway—the GOAT never completed a single mowing cycle. The GOAT was able to find the boundary of the first half of the lawn and circled around a few times, and then began to mow. Instead of mowing across the lawn, it mowed the same strip, up and back, for almost 20 minutes, and then moved over only marginally, so it was still getting half of the same strip of lawn. After an hour it hadn’t gotten half the lawn done, and eventually, it stalled on a sidewalk. Since a sidewalk is supposed to be one of the boundaries the robot will respect, I was surprised it even ventured onto it, making it a tripping hazard and prime candidate for being stolen. At the same time, it refused to cross the 24-inch walkway, which was well under the three-foot threshold.

Over a slow and painful back-and-forth with support over a few days, they first reminded me that the robot would only cross a threshold that was narrower than three feet. When I pointed out it was, they then returned saying that the robot could not cross any threshold, and i could just pick the robot up and put it back down on the other side and send it out to mow. This also did not work—the mower issued an error message saying it was out of the mappable zone, and picking the mower up means re-entering the PIN on the robot. Even worse, the robot refused to return to the dock in most cases. Even when the dock was placed in precisely the spot support recommended, the robot returned to the dock about 60% of the time. Still, I tried to send the robot out every day for a week to see if things would improve before giving up. 

Even on a perfectly flat lawn, that had just been mowed, the GOAT got stuck. Credit: Amanda Blum

No better on a perfect lawn

I then tried out the GOAT on a medium-sized backyard lawn that is flat and well-maintained, has no islands, and most importantly, is completely surrounded by fencing. It had just been mowed when we showed up. I just wanted to see if the GOAT would make one complete run. Even on a completely flat ground, the robot got its blades stuck every few feet, stopping and reporting an error. From the app, you can “ignore” these errors, so after checking for a block the first few times, I started ignoring these errors and asking the mower to continue. It would only continue a few inches before having another error. I tried moving the robot to another location inside the lawn to see if that would help, but it didn’t. At least on this lawn, the robot returned to dock. 

On my last attempt—a small, completely enclosed lawn that measured 30x15 feet—we experienced more of the same. The GOAT got stopped while going along the boundary, and when it started mowing the inside, it missed giant swaths of lawn and frequently reported errors. 

For every other robot lawnmower, this docking position would work, but the GOAT wasn't able to find it. Credit: Amanda Blum

A complete failure

I have enjoyed Ecovac robot vacuums; I trust the brand to make reliable robots for inside the house. But I have never had an experience like this, where every single aspect of a product fails. The GOAT has yet to accurately map a boundary for me, or to mow the entire space inside a boundary it creates. It is unreliable in coming back to the dock, and went into spaces it shouldn’t (like sidewalks) more than once. It is hard to connect to via Bluetooth, rendering some features like manual mode unusable, and couldn’t move across a lawn that was completely flat (and already mowed!) without reporting constant errors. 

Missing key robot lawn mower features

It feels silly to mention the price at this point ($999) since there’s very little I’ve said to convince you to buy this particular robot. This is mid to lower range for most lawn robots, and I’d be game to try the next GOAT to see how it changes. However, putting the features of the GOAT that don’t work aside, this robot didn’t include a lot of features that are important in other models, like the ability to affect mowing pattern, multi-zone support, the ability to see where your robot is on a map, or what areas of the map have and haven’t been mowed.

There's a big difference between a robot vacuum and a robot lawn mower. A robot lost in your living room can’t do a lot of damage. A vacuum can be stuck under a couch for weeks without anyone stealing it, or someone tripping over it. Outside, we need a lot of faith that our robots really are autonomous, and will do what they’re meant to, so they don’t become a hazard or become vulnerable to stealing. Perhaps another mower will convince me this RTK-less method of mapping works, but for now, I’m sticking to mowers that let you set a boundary, and then stick to it. For large lawns or those with steep inclines or rough terrain,, the Mammotion Luba 2 is incredibly reliable. For smaller lawns or those with more smaller turns and delicate areas, I recommend the Segway Navimow.