Water supply sub-system

In this sub-system, moisture sensor, temperature sensor, level sensor and motor play a major role. Soil moisture sensor (Sagar et al. 2017) checks the moisture content in the soil. If soil moisture is low, it continuously checks the moisture in the soil. Otherwise, the temperature sensor is activated. Pi checks if the temperature is less than 35°C. If the temperature is less than 35°C, the threshold level will be set to normal. Otherwise, the threshold level will be set to double the value of normal. Pi switches on the motor. The level sensor is also activated by the Pi to check the threshold level. If the threshold level is reached, Pi switches off the motor. Pi sends the status information to the farmer/gardener’s mobile phone. Figure 12.4 shows the working principle of water supply sub-system. The temperature and humidity output of a day are shown in Figure 12.5.