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Autonomous Mowers Save Energy

and Improve Quality of Lawns

Marco Volterrani, Michel Pirchio, Marco Fontanelli, Nicola Grossi, Centre for Research on Turfgrass for the
Environment and Sports (CeRTES), Department of Agriculture, Food and Environment, University of Pisa (Italy)

Autonomous mowers are machines that don’t have also proved to produce a superior turf
need an operator to perform turfgrass mowing. quality compared to traditional walk-behind
The first autonomous mower was produced in rotary mowers.
1995 by Husqvarna (Sweden) and was powered
by solar energy, while current autonomous mow- Based on scientific evidence, some trials have
ers are battery-powered machines. Autonomous been carried out to develop and study different
mowers usually move randomly within a precise autonomous mowing solutions and innovations
perimeter defined by a shallow-buried boundary for improved turfgrass management and turf
wire which generates an electro-magnetic field. quality control:
Once the autonomous mower reaches the bound- * Very little is known about the effects of auton-
ary wire or an obstacle, it stops and changes di- omous mowing on encroaching weeds, the aim
rection. It is an effective solution to cover areas of this research was to compare the effects of
with many obstacles, but leads to frequent over- an autonomous mower and an ordinary gas-
lapping. Some larger autonomous mowers use oline-powered mower on weed development
GPS technologies with the aim of reducing over- in an artificially infested tall fescue (Festuca
lapping. The working capacity of autonomous arundinacea Schreb.) turf with different nitro-
mowers ranges from 400 to 30,000 m . Auton- gen (N) rates. A three-way factor experimen-
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omous mowers can be equipped with razor-like tal design was adopted. Factor A consisted of
pivoting blades mounted on a cutting disc or with three N rates (0, 75, and 150 kg ha ), factor
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solid blades. Compared to conventional mowers, B consisted of two mowing systems (autono-
autonomous mowers have several advantages: mous mower vs. walk-behind gasoline rotary
* they help to save a great amount of time; es- mower equipped for mulching), and factor C
pecially for people who doesn’t like to mow which consisted of four different transplanted
the grass; weed species: (a) Bellis perennis L., (b) Trifo-
* they prevent humans from coming into con- lium repens L.; (c) Trifolium subterraneum
tact with dust, allergens, polluting gasses; L. and (d) Lotus corniculatus L. Of these,
* they are so silent that they can perform mow- B. perennis is a rosette-type plant, while the
ing even at night; other three species are creeping-type plants.
* given that autonomous mowers are usually The interaction between mowing system and
programmed to operate every day, the clip- transplanted weed species showed that the
pings are very small and are left in place; four transplanted weed species were larger
* they consume about one third of energy when mowed by the autonomous mower than
compared to gasoline powered rotary mow- by the rotary mower. The autonomous mower
er (Grossi et al., 2016). Autonomous mowers yielded larger weeds probably because the

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