Variable Rate Fertilization Control Test Platform Research On Deep Loosening And Fertilizing Machinery

With the rising of China’s population in recent years, the demand of food increasingly, but the continuously decrease of arable land makes the food problem increasingly serious, increasing per unit area production of cultivated land become more and more important. In our country, agricultural development is a big issue and precision agriculture is the way to figure out the problem effectively. Also,the technology of variable rate fertilization playsan important role of precision agriculture.It is great significance of farm landper unit area demanding fertilization,increasing grain yield and fertilizer efficiency, reducingthe volatilization harm to human body health from the artificial fertilizer working and the pollution of the environment. This paper designed a variable rate fertilization control system test platformfordeep loosening and fertilizing machinery. Based on the farmland fertilization electronic map, GPS module determine the field position and the system obtain corresponding application information,according to the speed of the machine, the system change the rotation speed of the distributing shaft, which makes the unit area meet the demand of application of fertilizer. The research work and conclusions of the experiment are listed as follows:(1) Based on the existing 1S-200 A type of deep loosening machine, designing the fertilizer distributing device and mole molding machine, manufacturing the prototype machine and doing field experiment. I put forward the improvement scheme based on velocity changes to satisfy the function of variable rate fertilization.(2) According to thegeneral design requirements, determining the scheme. After analyzing and comparing multiple solutions mainly in the components price, stability, and the using on generalization, determining to apply the single chip microcomputer to the system as the center element, stepper motor as the executive element of the system, the fluted roller feed distributoras the distributing device of the system. The single chip microcomputer controls the stepper motor driver, and then driving the stepper motor which could make the connecteddistributing shaft of the fluted roller feed distributor meet the required speed. The whole system adopts open-loop control.(3) Calculating and selectingfor the stepper motor, and then selecting the model of 57BYGH250 stepper motor. Using the fluted roller feed distributorwhich existing in the laboratory. After measuring and calculating, designing and processing for the distributing shaft.(4) Build the test platform, make the fluted roller at a certain position of axial working length, perform experiments under the different speed of the distributing shaft, weighrespectively the fertilizer consumption of distributing device in the 60 s time, useregression analysis to confirm the relationship between the fertilizer consumption of distributing device and the distributing shaft speed.(5) Build the test platform, fix the variable distributing control system to the chosen variable speed conveyor belt. The relative motion between the control system and the conveyor belt is used to simulaterelative motion between fertilizing machine wheeland the land, determining the speed of the conveyor belt by speed measuring module installedon the device.Using Keilc51 to programme variable fertilization program written to single chip microcomputer, and the single chip microcomputercalculate the stepper motor speed according to the given fertilizer consumption and the conveyor belt speed signal. Stepper motor drive the distributing axis synchronous rotation, and the distributing device do fertilizer operations.(6) Experiment on the test platform, the results show that hall speed measuring module works well,and the speed of conveyor belt measurement error is within6.00%.By changing the speed of conveyor belt, carrying on the experiment many times.The maximum error between actual fertilizer consumption and the given value is 11.43%. The small error prove the test platform control systemdesign meet the requirements of variable rate fertilization.