Abstract:
The development of soil infiltration device is designed to measure the amount of water entering into the soil. The instrument comprises of six units namely the percolation material, pond unit, sensor unit, control unit, display unit and storage unit. Firstly percolation material, the percolation material is made of coarse sand and cement. The cement serves as a binding material and the mixture was molded to the diameter of a pipe. Secondly, the pond unit is made up of a percolation tube of diameter 50.00 mm and length of 250.00 mm. The lower end of the tube contains the percolation material and it is inserted on the soil surface. The percolation tube is filled to one-quarter its volume with water. The third unit is the sensor unit. This is made of VL6180 sensor and it is placed on the upper end of the percolation tube. The sensor sends a pulse width to the target (water surface in the pipe) and the echo is reflected to the sensor. The time taken to travel to and fro is measured from the pulse width. Fourthly, the control unit consists of an Arduino (MEGA 2560) Microcontroller. The microcontroller converts the time taken by the wave to travel to and fro to distance (water falling depth) using the program. The output of the microcontroller is connected to the display system. Fifthly, the display unit consists of a liquid crystal display (LCD). The display unit displays the converted water falling depth output from the microcontroller on the screen. Lastly the SD-card unit serves as a memory or file where the measured water falling depth is stored. The data stored in the SD-card can be further processed. The measured distance (water falling depth) has resolution, minimum value and maximum value of 10 mm, 30 mm and 250 mm respectively. The rates of flow shown on sand-loamy, loamy and clay soil were 3 minutes, 5 minutes and 7 minutes respectively before reaching saturation. This instrument will be useful to farmers to determine the rate at which water infiltrate into the ground. This will enable farmers decide the type of irrigation practice and crop cultivation on the farm land. The device is easy to maintain and it is cost effective.
