Objective  There are problems of missed seeding and reseeding during the operation of cotton hole sowing machine used in Xinjiang region, which the driver could not find in time. A real-time monitoring system for cotton sowing quality was designed to solve these problems.

Method  The monitoring system uses the STM32F103C8T6 microcontroller hardware system as the lower computer, obtains the information of missed seeding and reseeding of cotton seeds through the counter-light photoelectric sensor and photoelectric encoder installed on the seed storage ring of the hole sower, and determines the quality of cotton sowing. The cotton sowing information is transmitted to the human-machine interface of the DWIN touch screen through the nRF24L01 module for real-time display. A test bed of cotton sowing quality monitoring system was built to verify the accuracy of the monitoring system through field tests.

Result  The results of the bench test showed that the system had the highest monitoring accuracies of 96.65%, 94.59% and 92.00% respectively for qualified seeding, missed seeding and reseeding when the speed of the hole sower was 30 r/min. When the speed of the hole sower was higher than 30 r/min, the monitoring accuracy decreased obviously. The results of field trial validation showed that the average monitoring accuracies of the system were 94.51%, 92.38% and 86.55% respectively for qualified seeding, missed seeding and reseeding. The analysis of the field trial data using SPSS software concluded that the trial data were statistically significant, and the cotton sowing quality data obtained by the monitoring system had a high correlation with the manually measured data, and the actual values could be reflected by the system monitoring values.

Conclusion  The system meets the demand for monitoring the quality of cotton sowing in field operation, and is of great significance for realizing the improvement of quality and efficiency of cotton planting.