Design of intelligent control system of potato precision planter

To solve the problems of low control precision of planting spacing and easily double planting and missing planting an intelligent control system of potato precision planter was developed in this study, which was constituted of a main control module, a detection module, a planting spacing control module, and a vibration intensity control module. A hydraulic motor was used to control the working of seed belt, a stepper motor was used to control the vibration intensity of the seed belt in order to achieve the auto-control of the planting spacing and the double or missing planting. The planting parameter could be set by touch screen according to the different potato varieties, area of planting and soil condition, and the information of planting spacing. As such, double planting and missing could be monitored. To test the machine, experiments were done. The test result showed that when the designed speed was 12-42 r/min, the deviation of actual speed and designed speed would be 56.3%, but it would be 9.20% after one detection cycle and average deviation was 6.09%. When the different planting spaces were planted by using same planting speed, the actual planting spacing could be controlled within the allowable range, and the average deviation between the actual planting spacing by using each planting speed and the setting planting spacing was 2.65%, 3.37%, 3.67%, 5.75% and 4.09%, respectively. When the planting speed was increased from1.16 to 1.91 m/s, the variance of the each planting spacing in 150-300 mm increased by 1.75, 3.12, 4.18, 1.50, 3.28 and 7.06 times, respectively and the higher the planting speed, the lower the stability was. As such, lower planting speed should be selected. The vibration intensity of seed belt was stronger, the replanting rate was lower and the missing seed rate was higher; When a strong vibration was reached, and vibration intensity of seed belt was in violent vibration shape, the planting speed was 1.74 m/s and seed quality was 50 g, the replanting rate was the least. When the vibration intensity of seed belt was in tiny vibration, the planting speed was 0.88 m/s and seed quality was 30 g, the missing seed rate was the least; the vibration intensity of seed belt had significant influence on the double planting rate and the vibration intensity of seed belt and the planting speed had significant influence on the missing seed rate. The primary and secondary order of the influence on the double planting and missing seed rate were the vibration intensity of seed belt, the planting speed, and seed quality. The optimal planting parameter: When a strong vibration was reached, and the vibration intensity of seed belt was in slight vibration, the planting speed was 1.16 m/s and seed quality was 35 g. The average missing seed rate was 2.31% collected by the missing detection module and the actual average missing seed rate was 2.22%, there was a deviation, but the average detection error was 5.25% and the largest error was 6.58%, the detection accuracy was more than 93%. When the actual missing seed rate exceeded the allowable range, it would be adjusted into the allowable range in 2-3 cycles, and the stability was good. The research results can meet the requirement of the actual planting operation, and provide reference to the further research and popularization and application of the intelligent control of potato precision planting equipment. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.