Research And Design Of Automatic Metering Water And Fertilizer Integrated Device In Wheat Field

The yield of winter wheat in the Huang-Huai-Hai area is high,but the utilization rate of water and fertilizer is low,resulting in waste of water and fertilizer resources.The water and fertilizer integration technology fertilizes irrigation according to the crop growth demand,improves the utilization rate of water and fertilizer,and has the advantages of saving water and fertilizer,high efficiency and high yield.Therefore,the paper studies and designs a water and fertilizer integrated device in the wheat field: the user presets the water and fertilizer amount,and the device automatically weighs the corresponding amount of solid water soluble fertilizer,and then controls to add the corresponding amount of water soluble fertilizer,and then the fertilizer is matched.The liquid is transported to the irrigation net of the wheat field.The experiment proves that the device can automatically complete the water and fertilizer ratio according to the preset water and fertilizer value,and achieve the intended design goal.The main working process of the water and fertilizer device is: the user sets the water and fertilizer amount on the mobile phone end,and transmits it to the single chip computer through the Wi-Fi local area network,and the single chip microcomputer starts the outer trough wheel type fertilizer device,and the fertilizer is discharged into the weighing tray directly below,and is weighed.Stop the fertilizer after the required amount of fertilizer;start the stepping motor to rotate the tray by gear transmission,dump the fertilizer into the cylindrical fertilizer tank below,and then step the motor back to the original position to prepare for the next fertilizer;Injecting water into the fertilizer tank,relying on the ultrasonic liquid level device to monitor the liquid level to control the injection amount of water in real time;after the water injection is finished,turn on the mixer and stir for two minutes to accelerate the dissolution of the fertilizer,and then open the suction pump to transfer the fertilizer liquid to the wheat field.The main research work completed when implementing the above workflow is:(1)Using Wi-Fi LAN to wirelessly connect the smart phone and the single-chip computer to realize the water and fertilizer amount on the mobile phone side;use the DS18B20 temperature sensor and the YL-69 soil moisture sensor to collect the real-time information of the wheat field and upload it to the mobile phone for users to view.(2)Design mechanical mechanism and control program to achieve more accurate dynamic weighing of solid water soluble fertilizer,and make test bench to measure fertilizer error;analyze the source of error,and study the method to reduce the error of fertilizer.(3)Select the ultrasonic liquid level device with good precision and sensitivity to monitor the real-time liquid level in the mixed fertilizer tank;install the liquid level device in the “riser tube type” and use the multi-tube split method to fill the mixed fertilizer tank to reduce the water injection.When the liquid level fluctuates,the accuracy of the liquid level monitoring is improved;and the cylindrical mixed fertilizer barrel is used to realize the monitoring and control of the water volume by the single chip microcomputer.(4)Combining the “two-position control algorithm” to design the program flow chart of weighing fertilizer and controlling water volume,the design program automatically reduces the dynamic weighing error of 25 g preset fertilizer amount to dry powder or small particle solid water soluble fertilizer,due to fertilizer There is a difference,the error value is expected to be controlled within 30 grams.Based on the autonomous mechanical design and program control,the device innovatively realizes the more accurate weighing of the solid water soluble fertilizer,and combines the control of the water volume to complete the water and fertilizer ratio,thereby realizing the integrated management of water and fertilizer in the wheat field.