Assessing an infrared-based seed drill monitoring system under field operating conditions

In this study based on the infrared seed sensor developed earlier, a seed drill monitoring system was designed and constructed. In the proposed monitoring system, seed flow sensors were installed individually on each seed tube so that the seed flow rate, as well as the presence or absence of seed flow, could be displayed on a graphical interface. The ground speed was measured with the Hall Effect sensor, and taking into account the mass flow rate of the seed, the sowing rate was calculated according to the seed mass sown per unit area. During operation, the system registered sowing data with the location information provided by the GPS module. The overall information from the sowing performance was then recorded on the embedded memory card and simultaneously displayed on the graphical interface. The proposed system was also provided with ultrasonic sensors to continuously measure and display the seed and fertilizer levels in the hoppers. The monitoring system was constructed and installed on a seed drill equipped with 13 sowing units. With three levels of ground speed and sowing rate during field experiments, the sensing system was assessed under outdoor operating conditions. The field test resulted in a correlation coefficient of 85% between the mean of the weighted data obtained from the scale and the mass flow estimates. The obstruction of the optical elements by dust seems to have had the most adverse effect on the performance of the proposed sensing system.