# Monitoring Autonomous Mowers Operative Parameters on Low-Maintenance Warm-Season Turfgrass
## 4 Discussion  
### Autonomous Mowers Performances  
The analysis of the working schedule of the two AMs gave results in terms of distance traveled, the percentage of area moved, and intersections, all useful data to evaluate the different work efficiency of the AMs in the same field conditions. Operative data of the distance traveled and area moved were not affected by the interaction of AM model and trampling level, but they were fundamental data to assess the work efficiency in terms of covered area. It resulted in being significantly affected by both independent variables and their interaction. A better work efficiency resulted in the plot moved by AM 450 due to the operative performance of this model, which results in a higher hourly work capacity than the AM 535 AWD. An opposite trend was observed for the intersections, which resulted in being evidently higher in plots moved by the AM 535 AWD from the Medium trampling level. This result is directly connected with the percentage of area moved, which resulted in being higher in the plots moved by 450 AWD due to the lower overlapping, but with higher distance traveled. Another relevant aspect that contributes to reaching a higher percentage of area moved in the same working time is the larger working width of 450X (24 cm) compared to the 535 AWD one (22 cm). These findings are according to [PERSON] et al. [20] findings, which suggested how a larger working width could improve the autonomous mowers' working efficiency. It is necessary to highlight how the operative performance of random trajectory machines is not very efficient in terms of the percentage of area moved, but this lack of efficiency is countered by the high frequency of moving events. In this regard, interesting results were obtained about passages, which, according to previous studies, are strongly correlated with the number of intersections [12]. In fact, as in the previous analysis, the number of passages resulted in being higher in plots moved by AM 535 AWD from the Low trampling level, and it might be connected to the AM 535 AWD pivoting rear body, which allowed it to perform more complex and articulated maneuvers than the AM 450X on the same limited area. Evident differences were found among the different zones inside the plots; the highest number of passages was always found on the edges of the plots, except for the control trampling level of 10 min, which revealed a higher number of passages in the central zone. The shape of the plots, together with their small area, contributed to increasing the probability that the robot encountered the boundary wire and made a high number of maneuvers to change direction [12; 13]. The operative parameters were studied extensively using the high-accuracy RTK-GPS system; however, the system encountered issues with GPS signal loss, which could hinder potential practical applications of RTK-GPS systems in AM path planning. According to [PERSON] et al. [9], an automatic mover based on differential GPS and IMU could play a crucial role in further enhancing positioning accuracy and improving AM performance. The daily recorded data of cutting height demonstrate how the height trend changed, depending on whether measurements were taken in the center or the corners. In general, turf height was higher in the corners compared to the center. This may be because robots were forced to work in a small area and encountered the boundary wire many times during the working period. When the robot mower detects the boundary wire, it stops, changes course, and then continues its work. Consequently, the robot mower managed the corners without cutting (since the cutting disk stopped rotating together with the robot mowers). As is visible in Figure 4, differences were detected also between the two autonomous mowers with the same trampling level; it is due to the constrictive characteristic.