Boundary wire, RTK or vision: how robot mowers find their way (and which suits your yard)

Two questions every robot mower has to answer

A robot mower's navigation system has two jobs: knowing where the lawn ends, and knowing where the mower is right now. Wired designs answer the first with a loop of cable around the perimeter and mostly sidestep the second, crossing the lawn in a random pattern and turning when they meet the wire. Wire-free mowers try to answer both, using satellite positioning sharpened by RTK correction, cameras, LiDAR, or some mix of the three.

This guide draws on installation documents from Husqvarna, Mammotion and Ecovacs, plus an independent RTK accuracy explainer. Manufacturers have an obvious interest in their own approach, so their comparative claims are attributed rather than repeated as fact. If you're still deciding whether a robot mower suits your lawn at all, start with the robot mower before-you-buy guide at robot mower before you buy.

Boundary wire: cheap, indifferent to the sky, fiddly to change

A wired mower follows a low-voltage signal from a cable laid around the lawn and around any beds it must avoid. Because that signal comes from the ground rather than from satellites, overhanging trees and tall houses don't affect it. Even Mammotion, which sells wire-free mowers, says in its wired-versus-wireless explainer that wired systems are unaffected by tree cover or buildings and are generally the cheaper option.

The price is labour. Husqvarna's installation tips say the wire can be held down with staples or buried 1–20 cm (3/8–8 in) deep in a slit cut with a spade, and they recommend mowing before you lay stapled wire, because long grass can lift it into the blades. Move a flower bed or add a patio and the wire has to move too. Wires also break. Husqvarna's wire-break article describes the signs (a flashing blue light on the charging station and a “No loop signal” message) and a repair process that involves halving the loop until the damaged length is found, trimming about 60 cm from each side of the damage and joining the ends with a crimped coupler.

One line in Husqvarna's prevention tips matters a lot in Canada: inspect the installation, especially before restarting the mower after winter. Frost and soft spring soil can lift stakes, so walking the perimeter each spring is part of owning a wired mower. If a working wire is already in the ground, a wired model such as the Husqvarna Automower 430X (Husqvarna Automower 430X review) can still make sense. For a very small, settled lawn, the Worx Landroid S WR165 (Worx Landroid S WR165 review) is the cheapest wired option in our coverage.

RTK: centimetre positioning that depends on open sky

RTK (real-time kinematic) positioning corrects ordinary satellite readings using data from a fixed reference point. That reference is either a base station on your property or a network service delivered over cellular or Wi-Fi. Husqvarna says its EPOS system gives centimetre-level navigation, while a 2026 accuracy guide from rtkdata.com describes centimetre figures as the best case in open sky with stable corrections, not a promise near buildings or under foliage.

The limit is sky view. Husqvarna's EPOS installation article warns that tall buildings and dense trees with crowns wider than about 4 m (13 ft) can block satellite signals, and it says a reference station must be mounted at least 2 m (6.5 ft) high with a clear view in all directions. Mammotion's own suitability guide lists layouts it doesn't recommend for its RTK mowers. They include lawns where tall walls or trees cover more than 30% of the area, and narrow lanes under 3 m wide and over 5 m long with tall trees or walls on both sides.

It helps to know what failure looks like. The rtkdata.com guide explains that when a receiver drops from a “fix” to a “float” solution, accuracy can slip from centimetres toward decimetres, and the mower may hesitate at boundaries, wobble or miss strips. It also says reflections off walls, glass and metal roofs can make the position jump.

Network RTK does away with the antenna but makes connectivity part of the navigation system. Husqvarna's cloud option needs stable cellular or Wi-Fi across the whole work area, with at least one bar everywhere, and is offered only in select markets. Mammotion's sensor comparison says base-station-free RTK is available in most of Europe but is still in its early stages in other regions, so Canadian and US buyers should confirm service at their address. Kress builds its line around network RTK (see the Kress KR172 review at Kress Mission RTKⁿ KR172 review). The original Mammotion YUKA mini, by contrast, depends on a reference station you'll need to find a good spot for (Mammotion YUKA mini H review).

Vision and LiDAR: reading the yard instead of locating yourself in it

Camera-led mowers recognise grass, edges and obstacles from images. They need no antenna and no wire, so setup is quick. Mammotion's comparison article, though, notes that vision depends on lighting, visibility and camera quality and is sensitive to shadows and weather. A camera has the hardest time where the lawn has no clean edge, such as grass fading into soil, mulch or a neighbour's lawn. The Sunseeker V3 review (Sunseeker V3 review) points out that Sunseeker supplies magnetic strips for areas the camera can't define on its own.

LiDAR builds a map from laser distance measurements. The same Mammotion article describes it as indifferent to light and colour and consistent under tree cover, which is why manufacturers pitch it at shaded yards where RTK struggles. We'd infer that it works best when there are trees, walls and fences to measure against, and you should ask the maker how it handles a wide, featureless area. The Ecovacs GOAT A3000 LiDAR (Ecovacs GOAT A3000 LiDAR review) is an example of an antenna-free design built this way.

Most new mowers are hybrids, so ask about the fallback

Few current wire-free mowers rely on a single sensor. Husqvarna says its vision-equipped EPOS models use the camera to keep mowing for a limited distance where the sky is obscured, as long as they can see grass. Its other wire-free models need open sky across the whole lawn or a short support wire in weak spots. Mammotion says its mowers can move into open sky to recover a lost signal, and that owners can check signal strength in the app and redraw boundaries away from poor-reception areas.

So for any hybrid, the useful questions are which sensor is in charge and what the mower does when it loses confidence. Does it pause, slow down, head back to open sky or carry on? Can you see positioning quality in the app at all? The rtkdata.com guide recommends mowers that display RTK status and fall back safely when signal quality drops. That's a reasonable thing to check in a manual or support article before you buy.

Matching the system to your yard

Walk the edge of the lawn and look up. Note where trees overhang, where the house or fences close in, and where the lawn narrows into a side yard. If most of the sky is open and the lawn is a simple shape, RTK, from a base station or a network, is the natural wire-free choice.

If big trees shade much of the lawn or buildings crowd it, look at LiDAR-led designs, RTK backed by vision, or a wire. If budget comes first and the layout won't change, the makers' own comparisons still put wire as the cheapest dependable option. If the lawn is small with crisp edges, a vision-led mower may be the easiest to set up.

Think about winter too. A base station, antenna or wire connection is one more thing to protect in the off-season, and the separate guide to storing a robot mower through a Canadian winter (robot mower winter storage canada) covers that routine.

From a tech standpoint

Choosing navigation starts with surveying your yard, not with a spec sheet. Wire works almost anywhere and costs least, RTK is excellent under open sky and fragile under canopy and between walls, and cameras and LiDAR fill gaps rather than removing every limit. Pick the system whose weak spot your yard doesn't have, and find out how a hybrid behaves when its main sensor loses confidence before you pay for it.