Development and Validation of Internet of Things (IoT) based Automated System for Controlling the Environmental Factors in Tunnel Farming

| Tunnel farming is getting popular in the farmer’s community of Pakistan due to the possibility of growing off-season vegetable crops with high yield in a controlled environment. In the current study, the development and validation of IoT system consisting of monitoring and control units were carried out for controlling the environmental factors in tunnel farming. Three tunnels were set for monitoring the environmental factors using temperature, humidity and soil moisture sensors. Two of three tunnels were fit with control units of exhaust fans and air heaters and a water pump for controlling the temperature and soil moisture. During the testing and validation of the system, temperatures recorded through DHT-21 sensor and thermometer in tunnel 1, 2 and 3 had strong correlations of 0.9986, 0.998 and 0.9978 respectively. Similarly, strong correlations of 0.9987, 0.9994 and 0.998 were found for RH (%) measured through DHT-21 sensor and RH meter for tunnel 1, 2 and 3 respectively. For soil moisture measurement, similar correlations were observed for resistive soil moisture sensor and oven dry method. It was explored that an increase in temperature through an air heater decreases the RH in tunnel 1 and 2 compared to tunnel 3 which has higher RH because it was not installed with air heater and exhaust fan. System controlled the temperature and soil moisture within adjusted limits of 22-27 °C, 17-23 % for tunnel 1 and 19-22 °C, and 19-23 % for tunnel 2.