Robot mower planner: area, slope and boundary
Step 1 — Area
Measure the mowable grass, not the property. Split irregular lawns into rectangles and add them up. Conversion: 1 acre is 43,560 sq ft; 1/8 acre is about 5,445 sq ft.
Compare your area with the mower's stated recommended area. Segway's site lists mowing area per charge and recommended lawn size by model; the manufacturer, not us, defines those (Segway).
Step 2 — Slope
Slope is rise over run, as a percentage. A 45% slope rises 45 ft over 100 ft of run — about 24 degrees, per Segway's description of its 45% tier.
Measure your steepest section, since that is where the mower may struggle.
Step 3 — Boundary: wire or wire-free?
Older robotic mowers require a border wire around the lawn that defines the area and sometimes the charging dock. Wire-free systems use RTK positioning instead, with cellular or a local antenna for correction; Wikipedia says RTK is currently the GPS approach precise enough for mowing without a ground wire. Segway says Network RTK is included at no extra cost where available and lets you check coverage by postcode (Segway).
Consider a wire if trees shade large parts of the yard or you have narrow passages; wire-free depends on sky view.
Step 4 — Read the fine print
- Area is per charge or per day? Segway lists mowing area per charge separately from recommended lawn size.
- Slope rating vs your steepest patch.
- Obstacles: Segway says its mowers detect pets, children and garden decorations; we haven't verified that.
- Cutting height, blades, rain behaviour: check the maker's manual.
What to avoid
- Buying on brand before measuring.
- Buying for the largest lawn area only; a mower struggles in the hardest 10% of the yard.
- Trusting any single number without the manufacturer's page.