# Transverse Movement Kinetics of a Unit for Inter-Row Crops--Case Study: Cultivator Unit
## 3 Results and Discussion
### Results of Experimental Studies of Row-Crop MTU  
To enrich the theoretical considerations, experimental research was also carried out. During these tests, a row unit was used according to the diagram in Figure 8c in two variants: variant A, a cultivator rigidly connected to the tractor, and variant B, a cultivator articulately attached to the tractor. Moreover, all of the results obtained are valid for other diagrams. The conditions for conducting field research are described in Table 3.  
During the inter-row processing of sunflower rows (Figure 9), the unit moved at a velocity whose mean value was 2.2 m\(\cdot\)s\({}^{-1}\). When the cultivator was rigidly attached to the tractor (variant A), the width of the protective zone of the mean value of the sunflower rows was 10.1 cm (Table 4). The value of the same parameter for the unit with the articulated attachment of the cultivator (variant B) was equal to 8.9 cm. At the statistical significance level of 0.05, the resulting difference of 1.2 cm is significant, as it is significantly greater than \(LSD_{05}\), equal to 0.3 cm (Table 4). Thus, the null hypothesis about the equality of mean values is rejected. The established one-sided value of the width of the protective zone for sunflower plants is 10.0 cm (Table 3). It follows that when the unit operates according to variant A, the specified zone is practically not disturbed. In the case of using the unit according to variant B, the width of the protective zone is reduced by 1.1 cm\({}^{2}\). \begin{table}
\begin{tabular}{c c} \hline \hline
**Index** & **Value** \\ \hline Recommended protective zone (cm) & 10.0 \\ Soil cultivation depth (cm) & 8.1 \(\pm\) 0.3 \\ Mean height of sunflower plants (cm) & 18.4 \(\pm\) 1.1 \\ Soil humidity (\%) & 15.9 \\ Soil bulk density (g\(\cdot\)cm\({}^{-3}\)) & 1.25 \\ Weed density (g\(\cdot\)m\({}^{-2}\)) & 79.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Conditions for inter-row crop culture of sunflower. Figure 9: Culturing unit at work. The oscillation variances in this parameter are arithmetically different (see Table 4). But this difference (0.33 cm\({}^{2}\)) is statistically insignificant and therefore random. The proof of this is the actual F-test value, which is 1.26. This is less than the table value of 1.39 at a statistical significance level of 0.05. Moreover, the error ranges of the sample values of the compared variances practically overlap (Figure 10). This is more proof that at least at a statistical significance level of 0.05, the null hypothesis about the equality of the compared variances of oscillations in the width of the protective zone is not rejected. That is, both sample variances represent the same general population. While variance evaluates the energy of the oscillation process, spectral density allows us to assess its internal nature, namely, frequency. As the analysis of the obtained data showed, for the unit according to variant A, the main part of the oscillation variance in the random process under consideration is concentrated in a narrower frequency range: 0-0.6 m\({}^{-1}\) (Figure 11). At a unit velocity of 2.2 m\(\cdot\)s\({}^{-1}\), this is 0-1.32 s or 0.2 Hz. The maximum value of the normalized spectral density occurs at a frequency close to zero. At the same time, the main spectrum of the variance in fluctuations in the value of the protective zone width for the option according to variant B is concentrated in a wider frequency range equal to 0-1.2 m\({}^{-1}\). For variant A, the range is 0-2.64 s or 0.4 Hz above the unit velocity. The maximum value of the spectral density is shifted toward higher frequencies (Figure 11).