What are robotic lawnmowers and how do they work?
Max Freeman-Mills breaks down the technology behind robotic lawnmowers.
If you’re tired of mowing and trimming your lawn all the time, there’s a good chance you’ll be interested in the rise of robotic lawnmowers.
These handy tools have gone from incredibly rare sights to much more common, to the point where the companies that make them are now way more visible – like Husqvarna, which recently became an official groundskeeping partner to Liverpool Football Club.
How do these mowers work, though, and what should you know about them? Read on to find out all the key details…
How do robotic lawnmowers work?
Robotic lawnmowers are both simpler than they look and yet still very complex. They work on your lawn just like a robot vacuum does on your floors – moving around independently and covering the whole thing in as many passes as it takes, returning to a base station to charge.
However, there are some key differences in how various models work. In particular, how they know where to stop mowing is important. Some systems involve the owner laying down magnetic tape or perimeter wire around their lawn, which acts as a boundary that the mower can sense to ensure it doesn’t accidentally eviscerate a flowerbed.
Others, though, rely on external sensors like cameras in combination with machine learning to detect obstacles and plants, edging around them that way instead. Either way, they should be able to autonomously mow your lawn.
How often do robot lawnmowers mow grass?
The reality is that most robot lawnmowers will go out as often or as rarely as you instruct them to (many will have connected apps that you can use alongside them).
However, the real point here is to have a lawn that stays the same length all year – meaning that your mower will trundle around daily or every couple of days, rather than leaving it to grow out too far.
Most robot mowers do better on shorter grass, just like a full-on lawnmower, so letting them take the ‘little and often’ approach is sensible.
Where does the cut grass go after a robot lawnmower?
There are some robot mowers out there that have storage systems and bins you can empty, but the majority of them don’t work that way. Rather, they instead leave grass clippings behind as they go.
Don’t worry, though – it’s much better than that sounds. For one thing, since they mow so often, these clippings are generally just a few millimetres long, making them way less bulky than you might think. They also therefore decompose really quickly and actually help to nourish your soil, which should lead to a healthier lawn.
Are robot lawnmowers better than doing it manually?
This is where things get a little tricky – as we’ve explained, robot mowers can be amazing for keeping a lawn in good nick and ensuring that you rarely have to do anything to it yourself. However, they can’t do everything perfectly.
In particular, they’re not great at the very edges of your lawn, so you’ll likely have to do some trimming every so often to keep everything neat. Also, the more irregular the shape of your lawn is, the more likely that your mower might occasionally miss a spot.
How expensive are robot lawnmowers and what are the best ones?
The robot lawnmower market is still a pretty nascent one, and that means the potential price variations are huge. You can spend thousands on a complex and sophisticated system with a massive range, but you can also increasingly find great options for way less than that.
B&Q, for example, has its most affordable robotic mower at £299.99 for the LawnMaster VBRM16, which is still rather expensive. The more you spend on a model with a great reputation, the better results you might get. One example that fits that bill is the Stihl iMOW 5 – which comes in at a far pricier £1,699 but is likely to excel in your garden.
