Design of an Optimized Second-order Soil-based Drip Fertigation Control System with Internet-of-Things Integration

Fertigation, which makes use of fertilizer injection into irrigation systems, has shown better results in terms of crop yield and water efficiency. To further improve this method, as well as make this more viable for farming use, this study developed a fertigation control system for efficient water and fertilizer crop distribution with Internet of Things (IoT) integration. The developed IoT control system functions as the autonomous feedback mechanism, collecting the data via flow sensor and sending it to the motor through a cloud server whose power would then be adjusted automatically to maintain the desired flow. To create the system, a second order transfer function for fertigation systems was derived, after which was optimized in the MATLAB Simulink space. The simulations of the closed-loop, single input, single output system tested compensator conditions, along with proportional-integral-derivative (PID) controller tuning. The test results showed that the steady state error compensators were not sufficient in optimizing the system. For full optimization, the implementation of the tuned PID controller allowed for the minimal overshoot along with a relatively quick time before stabilization. This study reduced the imprecise control of water supply along with the concentration of fertilizer in inducing plant growth.