Research On Seed Reserve Detection And Seeding Quantity Control Method Of Wheat Planter

The continuous increase of wheat production is inseparable from the development of agricultural mechanization and intelligence,and the planters play a vital role in the wheat planting operation.In order to obtain higher yields,it is necessary not only to prove seeding accurately,but also to ensure the uniformity of the seed particles.The traditional seeding control method is to control the rotation speed of the seeding shaft according to the forward speed of the planter to achieve the purpose of controlling the seeding rate.However,the traditional seeding control method ignores the effect of the seed height in the hopper on the seed quantity discharged per rotation of the flute roller,After testing,it is found that the seed quantity discharged per rotation of the flute roller will decrease as the seed height decreases,while the traditional control method cannot effectively eliminate the seeding error caused by the seed quantity discharged per rotation of the flute roller reduction.In order to solve the above-mentioned problems,this paper has carried out the research of seed volume detection and seeding rate control technology based on the change of seed volume.The main research work is as follows:1.The depth camera Kinect collected the change process of the seed volume in the seed box in the seeding,analyzed the change of the seed height above the seed metering port and the change of the seed filling rate;according to the change process of the seed volume,the ultrasound with a smaller beam angle was customized.The sensor was used to measure the seed height above the seed metering port,established a regression model of the seed height detection,analyzed the reasons for the detection error of the ultrasonic sensor,and proposed a compensation algorithm for temperature compensation and eliminated the corresponding time of the hardware,while fusing the sorting algorithm and the mean filter algorithm.The filtering algorithm denoised the measured value to improve detecting accuracy.2.Take the flute roller of Jiangsu Xintian Machinery Manufacturing company as the model to built a seed metering flow measurement test equipment.The relationship between the seed height above the seed metering port and the seed quantity discharged per rotation of flute roller was studied;the corresponding seed height when the seed quantity discharged per rotation of the flute roller is reduced was defined as the minimum seed height;Analyzed the correlation between the minimum seed height and the rotation speed of the seeding shaft,and determine that the correlation is weakly correlated;established a seeding quantity discharged decision model based on the seed height.According to the seed quantity discharged per rotation of flute roller at the beginning and the end of the seeding,the seeding quantity discharged compensation coefficient was 1.18;the comparison experiment between the seeding control method based on the seed height and the traditional seeding control method was carried out.The accuracy of the seeding control method based on the seed height was higher than that of the traditional seeding method.The seeding accuracy of the control method based on the seed height was 4.07% higher than the traditional seeding control method,and the coefficient of variation of the control method based on the seed height was 3.56%lower than the traditional seeding control method.3.The overall design of the precision metering control system was carried out,and the seeding control motor of the planter was modified according to actual operation requirements;the upper computer control system based on Em Win,the main control system and monitoring system based on ARM were established.Each system has carried out detailed software and hardware structure design;the embedded operating system was added to realize the operation of the upper control system;designed the optocoupler isolation circuit to facilitate the detection of the forward speed of the planter;the serial communication protocol was designed to realize the data transmission between upper computer and the main control system;the power supply module was designed to achieve stable power supply to each subsystem.4.The static tests including a seed quantity discharged per rotation of the flute roller calibration test and a consistency test of the seed quantity of each row was carried out.The measurement result was that the seed quantity discharged per rotation of the flute roller was 12.55 g,and the maximum value of the consistency coefficient of variation of the seed quantity of each row was 3.26%;In the field experiment of the precision seeding control system,the maximum error of the average number of seed particles between the beginning and the end of seeding was 0.28,the average coefficient of uniformity variation was 31.49%,and the average standard deviation was 2.56.It proved that the precision seeding control model based on seed height is correct and can effectively improve the quality of seeding operations.