Measuring the operative performance of autonomous mowers on slopes

Autonomous mowers are becoming more and more popular in green areas. Small autonomous mowing machines are also used for weed control and cover crop management in vegetable and tree crops. Slope is one of the main factors affecting the choice of an autonomous mower. The aim of this study was to measure the operative performance of three autonomous mowers in slopes. The machines were characterized by linear random trajectories. One of the three machines was all-wheel drive. Tests were carried out in different slopes: high slope, medium slope and flat plot. In the high slope plot the number of failures and the quality of the turfgrass were assessed. In the medium slope and the flat plots the trajectories were registered with an RTK-GNSS tracking device and then processed with a custom built software to determine the percentage of area mowed during time. The all-wheel drive autonomous mower, was the best option in the high slope plot showing no failures during the cutting sessions and a excellent turf quality (9/9). In the medium slope plot, all mowers showed good performance cutting almost 100% within the set working time. No significant differences were observed on the flat plot among the autonomous mowers in terms of area mowed. The all-wheel drive machine gave slightly better results in the medium slope plot after 10 minutes (94% vs 87% of area mowed). This study confirms the flexibility of the autonomous mowers, which can be suitable and easily adaptable to different landscape contexts showing excellent performances even on slopes. The four wheel drive technology is necessary to avoid failures in high slopes. In the light of this, autonomous mowers could safely replace ride on lawn tractors which can be dangerous for roll over issues.