Here's a reprint of an excellent Mow-How article from Segway Navimow.
The Mow-How: Why Navmiow X4 Uses NRTK + 360° Vision Instead of LiDAR
The question we keep getting: "Why no LiDAR on a flagship model?"
Since the Navimow X4 launched, this has been one of the most common questions in the community. It's a fair one. LiDAR is widely associated with high-end tech. But sensor selection isn't about what sounds most impressive, it's about what performs best in the environment the product actually lives in.
For the X4, that environment is the large yard.
Here's why Network RTK + 360° Vision is the superior choice for big acreage.
(1) Large yards expose LiDAR's limits
LIDAR EXCELS IN SMALL, FEATURE-RICH SPACES. THINK OF A ROBOT VACUUM NAVIGATING A LIVING ROOM (WALLS, FURNITURE AND TIGHT CORNERS) THAT GIVE THE LASER PLENTY OF SURFACES TO BOUNCE OFF AND BUILD A MAP FROM.
Large open lawns are the opposite problem. In the middle of a wide, open yard, a LiDAR sensor has very little to work with. The laser shoots across empty space or reads repetitive grass patterns. In these featureless environments, LiDAR positioning accuracy degrades significantly.
The X4 is built around an RTK-first strategy. In the vast majority of mowing environments, Network RTK delivers all the precision and stability required. The 360° Vision system acts as a seamless backup for the rare scenarios where satellite signals are obstructed, not as a competitor to RTK. Adding LiDAR on top of this architecture would not improve positioning performance; it would only add cost and complexity.
(2) Why Network RTK changes everything
TRADITIONAL RTK DELIVERS CENTIMETRE-LEVEL PRECISION, BUT IT COMES WITH A HARDWARE BURDEN: BASE STATIONS, ROOF-MOUNTED ANTENNAS AND FIDDLY INSTALLATION.
Network RTK removes all of that:
- No hardware required. No base station, no antenna, no installation. Connect to the network and the mower is ready to go.
- No distance limits. Traditional local base stations have a limited transmission range and can lose signal on large properties. NRTK uses 4G cellular connectivity, so as long as there is a network connection, there are no distance boundaries. So ultimately: ideal for expansive lawns.
- Triple-band multi-mode GNSS. The X4 locks onto multiple satellite constellations simultaneously, providing significantly stronger resistance to interference and light tree cover than single-band systems.
- Free for life. NRTK service is completely free for consumer users, with no subscription fees or hidden costs.
(3) The backup system: 360° Vision SLAM
UNDER A DENSE OAK TREE OR ALONGSIDE A TALL STONE WALL, GNSS SIGNAL CAN WEAKEN. RATHER THAN LIDAR, THE X4 USES A THREE-CAMERA 360° PANORAMIC VISION SYSTEM FOR THESE SCENARIOS.
Vision has a longer effective range than LiDAR and reads textures and landmarks that laser point clouds miss. Even if one side of the mower faces open featureless lawn, the other cameras maintain a lock on the house, a fence line or a distant tree, preserving centimetre-level positioning without interruption.
The self-developed AI handles lighting variation (shadows, glare, low sun angles) more robustly than standard vision systems, ensuring the handoff between RTK and Vision is seamless.
(4) Obstacle avoidance: semantic recognition over point clouds
LIDAR DETECTS THAT SOMETHING IS THERE. IT CANNOT TELL YOU WHAT IT IS.
The X4 pairs 360° Vision with ToF (Time of Flight) depth cameras, enabling semantic recognition across 200+ object types. This means the mower responds differently to a child or a pet than it does to a fallen branch — making smoother, more considered manoeuvres around living things while handling hard obstacles more assertively.
Adding LiDAR alongside this system would not make the mower safer. It would add cost and weight with diminishing practical returns.
THE VERDICT
THE X4'S ARCHITECTURE WAS CHOSEN BECAUSE IT IS THE MOST STABLE, EFFICIENT AND USER-FRIENDLY APPROACH TO MANAGING A LARGE, COMPLEX PROPERTY:
- Network RTK handles precision positioning across open ground.
- 360° Vision SLAM covers the gaps in signal-limited areas and identifies what's in the mower's path.
- NRTK removes the hardware complexity of traditional RTK setups entirely.
This isn't about winning a spec-sheet comparison. It's about building a system that reliably masters your backyard.
This is the first instalment of The Mow-How. Let us know whether this level of technical detail is useful, or whether you'd prefer a shorter format. What should we cover next? Battery thermal management, 4WD torque distribution, or mapping algorithms? Let us know!
