The Eufy E15 robot mower is one of the first on the market that aims to let you spend less time dealing with your garden lawn and navigates via front-facing cameras.

Eufy

Back in the heady summer months, my wife and I were the lucky recipients of an always-delightful visit from my mother-in-law. Spotting the unusually immaculate lawn, she joked that, with my penchant for gadgetry, I probably had a robot to do it for me. When I told her that, actually, yes, I did, and pointed at the Eufy E15 robot lawn mower, her face was quite the picture.

This anecdote suggests that while robot cleaners for the home are now commonplace, the garden equivalent is a relatively new concept. That said, Eufy isn’t going to have the market to itself for very long.

What differentiates the Eufy E15 (£1,499 RRP – but currently available with £300 off) and one of its indoor siblings, the all-in-one, self-emptying, self-cleaning Eufy E28 mop/vacuum (£999 RRP but also available for £300 less) which I’ve also had around the house for a few months), is that they are autonomous, using sensors to map and navigate their way around the world.

While self-driving lawnmowers already exist, they rely on GPS or a buried perimeter wire to navigate and require manually driving your lawnmower around the garden to set up, and who wants to do that? Older technologies on cleaning robots also rely on bump sensors and infrared sensors to know when they hit a wall or to see one in front of them, as well as “cliff sensors” so they can avoid falling downstairs.

These days, most autonomous devices use smarter technologies enabling them to build up an actual picture of their environment and work out how to move around a space efficiently, so they can do their work more quickly while using less energy.

Cameras vs LiDAR

To map space and to “see” the Eufy E15 lawnmower uses a single front-facing camera, and a computer vision technology called visual simultaneous localization and mapping (vSLAM). The Eufy E28 cleaning robot also has a camera for object detection, but uses light detection and ranging (lidar) — a rapidly spinning laser on a central unit on top of the robot — to build up a detailed picture of the world around it and map the space.

As the laser spins around the device, lidar devices can map spaces quickly. This means that they are faster to get going and to relocate themselves if they are moved. The speed is also useful if the map needs to be updated.

Conversely, with a single camera on the E15, it did take a while to map my relatively small space, and I noticed that it had to move around many times to find itself in space once it started. That said, this made little difference, as once set up, I just let it get on with it in its own time, which is, of course, the whole point. The fact that it wasn’t speedier mostly annoyed the cat, which had to contend with a thing invading its space both outside and in – and looked equally appalled at both.

Another advantage of lidar is that it doesn’t need light to work, unlike RGB cameras, which do. As such, the E15 would only operate in the garden half an hour after sunlight and will stop well before it — information it knows from being online. It also isn’t keen on rain and would scurry home to its base if it detected a shower, as much because rain stops it seeing well, rather than not being water resistant.

The downside to lidar is that it is relatively costly. It’s the reason that Tesla does not use them for its cars, despite the assistance they might bring to its advanced self-driving capabilities. At launch, the E15 retailed in the UK for a not inconsiderable £1,399 and, using lidar, would have pushed it above the £1,500 mark, which would be a step too far, even for the well-heeled tech enthusiast that this is aimed at.

In the garden

Navigation aside, the Eufy E15 was a good lawnmower. As promised by VSLAM technology, it mapped my very simple oblong lawn without issues.

It comes with a large charging base, which needs to be secured with the large screws provided. You’ll need a good Wi-Fi signal at the base to receive commands from the app, but the unit doesn’t need it while operating.

To accommodate getting power to it, the first place I put the base wasn’t entirely flat and the E15 kept getting stuck at one spot for no reason I could fathom. Fortunately, the 3.4-meter power cable meant I could relocate it to the top of the garden with a downward slope, after which it was happier. It takes about two hours to charge and naturally will return to replenish itself when it needs to, but my garden wasn’t big enough to ever cause it any power issues.

At the Cutting Edge?

The E15 will avoid cutting anything too high to avoid damaging beds and this is why I assumed that on the first run, it left the edges of the lawn untrimmed. You can adjust the spacing to let it get closer to the lawn edges, which I tried. However, doing so made no appreciable difference. I then added ‘Must Go’ zones to the map, placing these over the uncut areas — but this also made no difference and the edges remained stubbornly untrimmed. Using the conventional mower to sort this out didn’t take long. While there were several software updates over the summer, I never got the issue resolved, but I remain optimistic that Eufy will continue to improve things in this regard.

In the home

Inside the E28 felt like a more mature product on the software side. The lidar-assisted mapping was fast and quick, and it had no issues identifying the mix of floored and carpeted areas. I was able to edit each room by name and once I adjusted the mopping and vacuuming strength and created a schedule, I was impressed by it. The portable deep cleaning unit proved its worth on one occasion, and it required less general maintenance than my previous incumbent.

However, while the RGB camera allows it to do basic object avoidance, the two mats for the cat’s food and water and the shoelace we often use as a play string for her were regularly caught up inside the rollers of the E28, as did the shoelaces of a boot fallen on its side. This meant that to give the unit its best chance, it still required a tidying run before it set off. Robots that can see these things and more things out of the way by themselves would be most welcome, and we’re surely not far off from these arriving.

Future Plans

The Eufy E28 is an accomplished cleaning robot and (edges aside) the Eufy E15 lightened the load for me in terms of garden maintenance. As for the battle of the sensors, the camera VSLAM technology on the former and the lidar/camera combo on the latter proved effective for both setup and navigation.

However, when it comes to AI-powered object recognition, I feel that there is more to come. As Eufy proved by unveiling a robot cleaner at IFA last September that could literally navigate stairs, Eufy is not shy about innovating in terms of hardware, so, as we approach CES I’m and I’m eager to see what progress Eufy has made on the software side to make its very cable current robots even smarter.