Design and simulation of a Fertigation control system for roses "for Uganda Hortech Limited (UHL)"

Abstract

Uganda Hortetch Limited is one the producers of roses in Uganda. However, they use archaic methods of fertigation which calls for improvement for better results. This project was therefore focused on the design and simulation of fertigation control system for the above mentioned company. Inefficient management of nutrient inputs has put a large constraint on the environment and human's health. Indiscriminate use of nitrogen and phosphorus fertilizers has led to ground water pollution. So the farmers have to pay close attention to nutrient management and incorporate the concept of balanced plant nutrition into their fanning techniques. The balanced nutrition level to plant is provided by managing PH and Electrical conductivity(EC) level of fertilizer solution according to soil pH and electrical conductivity. Developed system comprises of two sensors to measure pH and EC of the fertilizer solution and soil. Microcontroller will turn on and off particular solenoid valve to pore the fertilizers into the mixing tank according to the pH and EC level in the mixing tank solution. LCD is used to display the computed results. PH and EC level of fertilizer solution is maintained on the basis of output readings of EC and pH sensors. In the course of the study, data was collected through literature review, discussions, consultation, extensive interviews and personal observation at site to come up with the best results of the study which led to concise and appropriate material selection that best suit the modeled system on the hardware. The system was modelled using proteus software followed by simulation and finally Embedded C Programming language for coding using Arduino. The design consists of a microcontroller to receive input signals from the EC and PH sensor, processes the data acquired and then sends the output signal to the LCD were they are displayed on the screen via its digital output pins. Results showed that the best PH ranges for Roses to survive and produce more yield was 5.5-6.5 and that of the EC was 1.2-1.8. The system's validity was tested using Parameter Variability-Sensitivity Analysis and its economic viability were determined during the course of the study by use of NPV method and it showed that the project is viable once it's being implemented.