Wire-Free and GPS Robot Lawn Mowers Explained

Every robot mower needs a boundary. The first generation got it from a perimeter wire buried around the lawn: the mower senses the wire’s signal and turns back. Wire-free mowers get it from a map instead. The mower knows its own position precisely enough to follow a boundary drawn on a tablet, and that precision comes from RTK, real-time kinematic correction of a satellite position.

Plain GPS is accurate to a few metres, which is useless at a bed edge. RTK fixes that by comparing the mower’s satellite signal with the signal at a reference station whose position is known exactly, and correcting the difference in real time. Husqvarna calls its system EPOS and lists an EPOS reference station in the CEORA kit; ECHO calls the TM-2050 a GPS-RTK mower; Kress calls its line RTKn and, per Mowing Magic, uses a Kress RTK network with no perimeter wire. All three publish accuracy of about 2 cm. Source

RTK needs sky. MowScout’s review of a satellite-guided commercial mower says heavy tree canopy and tall building shadow degrade the RTK fix, and a mower without a fix stops. On a site assessment we walk every zone and look up: a lawn between two tall buildings, a park under mature oaks or a cemetery with dense tree cover may need a wire, a mix of guidance types or a crew. Source

RTK also needs its reference. Some makers run a network of correction antennas, and the mower works only within range of one; MowerRanker says that is the case for Kress RTKn, and Mowing Magic notes that a dealer installs each mower. Others ship a reference station with the machine, as Husqvarna does with the CEORA kit, so the site carries its own. A Kansas club checked its cell signal and the distance to a GPS base station before committing, according to Golf Course Industry. Do the same. Source

Finally, RTK tells the mower where it is, not what is in front of it. Obstacle handling is a separate system: ECHO says the TM-2050 uses sonar units to detect obstacles even on slopes of up to 45%, and USGA reports that robot mowers are programmed to move around obstacles, including golf balls. The USGA also notes that reel robots can get stuck or throw faults that need a reset, so plan for a person who answers those. Source

We are not tied to one navigation system or one maker. At the free site assessment we map the sky view of every zone, check where a reference station or antenna would sit, note the zones that need a wire or a crew, and pick the machine that fits. Then we lease it on a 3-year lease with a $1 buyout, set the boundaries, train the crew to redraw them when the site changes and service it.