Development And Experimental Of Online Detection Device For Soil Column Irrigation Capacity Based On Arduino

Infiltration is the process of irrigation water into the soil,soil infiltration performance is an important parameter to characterize soil moisture.The research of soil infiltration is great significance in regulating the soil water status of farmland,determining the technical parameters of water saving irrigation,regulating rainfall runoff,keeping water and soil,water resources planning and design and evaluation management.In order to obtain the parameters of soil infiltration performance in the process of obtaining the relevant parameters of the whole process of participation,the test process takes a long time,the test workload,access to the amount of data and the accuracy is not high and other prominent issues.In this paper,an intrusion test of soil infiltration was developed,and an automatic detection device for soil infiltration performance based on arduino was developed.The main structural parameters were determined by theoretical analysis and numerical simulation.And the accuracy of the detection of the device to verify the test,the main conclusions are as follows:A new automatic device was designed for the soil column infiltration ability,which was mainly composed of a sensor position adjusting device,a soil sample lay device,a water supply device,a FDR soil moisture sensor,a CLZ-A pressure-strain type sensor,a arduino mega 2560 development board,a arduino Uno development board,and a TB6600 byte rotor driver and upper desk software.The sensor position adjusting device was composed of the FDR soil moisture sensor,a 28BYJ-48 byte rotor,two 42BYGH47 byte rotor and four limit switch,the FDR soil moisture sensor was driven by the byte rotor in the horizontal direction,the FDR soil moisture sensor was driven by the byte rotor in the vertical direction.Two limit switch was fixed on both sides of the FDR soil moisture sensor in the horizontal direction,the other limit switch was fixed on both sides of the FDR soil moisture sensor in the vertical direction.The soil sample lay device was cylinder made of acrylic materials,there was have several holes in the cylinder,the probe of FDR soil water moisture sensor could go in or go out from the holes.The cylinder was driven by a 57BYG250B byte rotor until the soil moisture sensor probe could go in or go out from the holes in the cylinder.Water supply device composed of a Markov bottle,a pressure-strain type sensors and a support board.The pressure-strain type sensor was placed in the bottom of Markov bottle.The signal of the pressure-strain type sensor was transformed into digital signal by HX711 24 bit A/D transfer,then the digital signal was inputted into arduino Uno interface.FDR soil moisture sensors could response digital signal,which was inputted into single chip interface.The 28BYJ-48 byte rotor was controlled by the ULN2003 byte rotor driver,the 42BYGH 47 byte rotor and 57BYG250B byte rotor were controlled by the TB6600 byte rotor driver,both ULN2003 byte rotor driver and TB6600 byte rotor driver received control signal came from single-chip.The area of FDR soil water moisture sensor detect was a cylinder,when the FDR soil moisture was driven into the soil column in the horizontal direction,there was a one-to-one correspondence between response of FDR soil moisture sensor and quality content of water in the soil column.For this reason,with the infiltration continued,the wetting front was moving downward,the detection device obtained the change of quality content soil moisture.According four basic assumptions of Green-Ampt,when the wetting front had arrived the highest position of area of FDR soil moisture sensor detected,the response of sensor would become bigger until the wetting front had reached the lowest position.When the rate of response changed less than 5%,the sensor position adjusting device would adjust the FDR soil moisture sensor position,next position would be detected.Main interface of upper desk had designed using the LabVIEW software,it could judge the position of wetting front according the response of FDR soil moisture sensor.To evaluate the device' s measuring accuracy,the FDR soil moisture sensor had detected in a series soil sample of different bulk density whose were 1.15g · cm-3,1.20 g · cm-3 and 1.25 g · cm-3 respectively,each bulk density soil sample were tested three times,the infiltration water head was 10 mm.The response of FDR soil moisture sensor was measured by the device and a standard data which was used as the comparative reference respectively,those standard data have obtained from the ways of drying soil sample.Meanwhile,the response of pressure-strain type sensors also have detected in those soil sample,which response have measured by the device and a standard data which was used as the comparative reference respectively,those standard data have detected by test person.The results shows that,The ensor position adjusting device and soil sample container all have returned to the initial position successfully,and during detected,the FDR soil moisture sensor' s probe all had go in or go out from the soil column successfully,that was to say,the device run reliably.With comparing standard data,the maximum and the minimum relative measurement error of the soil moisture were-4.4%and-1.5%separately;With comparing actual data,the maximum and the minimum distance measurement error of wetting front position were 9 mm and 2 mm;With comparing the data by Manual measurement,the maximum cumulative infiltration error was 1.2 g.From the above,the device developed could be used as soil column infiltration ability automatic test platform.