Monitoring system for scoop-wheel maize metering performance based on motor direct driving

In order to solve the problem of the low accuracy of monitoring metering quantity and seeding spacing of non-direct-drive maize scoop-wheel metering device, a monitoring system of maize scoop-wheel metering device based on stepping motor direct driving was designed. The system took STM32 as the core, used a photoelectric sensor to detect metering quantity and realized the monitoring of the seeding spacing based on the adjacent time interval of photoelectric pulse signals. The bench test showed that the average accuracy of monitoring metering quantity was 98.55% with a standard deviation of 1.4% at the set vehicle speed of 3-8 km/h. Compared with the theoretical value of seeding spacing obtained by analyzing the movement process of adjacent seeds, the average absolute value of the error of monitoring seeding spacing was 2.84 cm with a standard deviation of 3.66 cm, and the qualified index of seeding spacing was greater than 97.1%, which met the actual requirements of monitoring metering quality. The results of the study can provide a reference for the monitoring technology of maize metering quality.