Robot mower without a wire: how do GPS, RTK and EPOS work?
No need to bury cables, simply set up a no-go zone for the trampoline and adjust the mowing area via an app whenever necessary: wireless robotic mowers make life a lot easier. But how does such a robot actually know where your lawn ends?
A wireless robotic mower uses satellite navigation, RTK corrections and virtual boundaries to determine with centimeter-level accuracy where it may and may not mow. Sounds quite technical. In practice, it’s actually pretty straightforward.
We explain how GPS, RTK and Husqvarna EPOS work together, when wifi or a reference station is needed and, above all, when wireless mowing is a good choice for your garden.
How does a wireless robotic lawn mower know where to mow?
With a classic robotic lawn mower, the boundary of the lawn is physically marked with a boundary wire. That wire runs around your lawn and tells the robot where to stop.
With a wireless model, this is done digitally. You map out the boundaries of your lawn via the app and determine where the robot is and isn’t allowed to go.
This can be useful, for example, if you have a trampoline, pond, or flower bed. Want to add a section of lawn later or temporarily close off a zone? Then you simply adjust the digital map.
Of course, the robot needs to know very precisely where it is for that. And that’s where GPS, RTK, and EPOS come in.
GPS or RTK: what is the difference?
GPS sounds accurate, but regular GPS is actually not precise enough for a robotic lawn mower. A standard GPS signal can have a deviation of several meters. For your smartphone, that makes little difference: you can still perfectly tell which street to take. For a robotic lawn mower, a deviation of several meters is a different story. It could end up mowing over a flower bed.
That is why wireless robotic lawn mowers use GNSS combined with RTK technology. GNSS is the collective term for satellite navigation systems such as GPS. RTK then provides much more accurate positioning.
In short:
- GPS/GNSS: knows roughly where the robot is located.
- RTK: knows much more precisely where it is located, down to a few centimeters.
- Virtual boundaries: then determine where it may and may not mow.
This gives the robot, as it were, a digital map of your garden.
Where does the robot get that RTK correction from?
There are various systems for that. At Husqvarna, for example, this is done via EPOS, and depending on the model and the installation, the correction information can be provided in different ways.
1. Via the Husqvarna Cloud
With this solution, your robotic mower receives the necessary correction data via the internet. The service is free, but your robotic mower must have a stable internet connection while mowing. This can be via Wi-Fi or, on models equipped for it, via the mobile 4G network.
And that is where a common misconception lies: Wi-Fi on your terrace does not automatically mean Wi-Fi at the back of your garden. Do you have a long plot or a large garden? Then it is best to first check whether the signal is strong enough everywhere.
Some Automowers, such as the 308V and 312V, come standard with only Wi-Fi. Other models also have a built-in 4G connection.
Do you have insufficient Wi-Fi coverage but a good mobile network? Then Dekens can install an Automower Connect kit on suitable models. This allows your robotic mower to communicate via the mobile network as well, without any additional monthly subscription fees.
2. Via your own reference station in the garden
Do you not have a stable internet connection in your garden? Or do you want even more accurate navigation? Then your own reference station, such as the Husqvarna EPOS RS1, is an interesting solution.
This station receives satellite signals itself and sends the correction data directly to the robotic mower. No internet connection is required for this.
The RS1 reference station has a range of up to 100 metres around the station and offers accuracy of up to approximately 2 centimetres. Via the Husqvarna Cloud, that accuracy is approximately 5 centimetres. This difference can be especially interesting when you want to mow very precisely along lawn edges.
The location of the reference point is important, however. It must have sufficient visibility of the sky and be positioned so that the robot can receive a stable signal throughout the entire mowing area.
Trees, buildings and other obstacles in particular can affect reception. That is why Dekens determines the best location for the reference station during installation.
The RS1 station is compatible with various Husqvarna NERA models and with the 308V, 312V and Aspire R6V. For those last three models, the station must be installed by a Husqvarna dealer. Dekens can also help you with that.
Is a wireless robotic lawn mower suitable for every garden?
Not entirely. No matter how smart the technology is, every garden has its own challenges. Slopes, obstacles, and the layout of your lawn all help determine which solution works best. In our blog ‘The best robotic lawn mower for your garden’, you can read which robotic lawn mower best suits your garden.
The best robotic lawn mower for your garden: how to make the right choice
How do you set up a wireless robotic lawn mower?
One of the biggest advantages of wireless mowing is that you do not have to bury a boundary wire. The boundaries are set digitally. Depending on the system, this is done via the app, and you guide the robot along the desired boundaries. You can then set mowing zones and no-go zones.
For example:
Mowing zone: the entire lawn.
No-go zone: around the trampoline.
Extra mowing zone: a second section of lawn that the robot may also access.
That sounds simple, and for a straightforward garden it often is. But the accuracy of the installation remains important. A boundary along a pond, a narrow passage between two patios, or a garden with multiple levels requires more attention than a simple rectangular lawn.
Conclusion
So a wireless robotic lawn mower does not simply run on GPS alone. The combination of satellite navigation, RTK correction, virtual boundaries and additional technology ensures that the robot can find its way without a boundary wire.
But technology alone is not the whole story. A small urban garden with high walls requires something different from an open lawn of 2,000 m². And a garden full of trees, borders and narrow passages calls for yet another approach.
That is why at Dekens we always look at the garden first, and only then at the robot.
We are happy to look at the options together with you. This way, you will not only know which robotic mower is the right fit, but also which navigation technology your garden needs.
