Design of Fuzzy Logic System for Disinfectant Liquid Monitoring Using the Internet of Things

New health protocols have been carried out to prevent, if not, to reduce the coronaviruses' spread, such as wearing masks, keeping body hygiene, and social distancing. One way to keep body hygiene is by spraying disinfectant liquid all over the body before entering a room or office. A safe disinfectant liquid should kill the viruses on the body surface without irritating the skin, and one way to synthesis the safe disinfectant liquid is electrolysis. Real-time monitoring of the liquid during electrolysis is important to get the safe disinfectant liquid. Monitoring Disinfectant (MODIS) based on the Internet of Things (IoT) is proposed to automate the electrolysis process using sensors and actuators. MODIS should conduct two processes simultaneously, which are determining the timing of the electrolysis and assessing the liquid quality. Fuzzy Logic (FL) system was developed to fulfill the needs. The inputs were pH and Oxidation Reduction Potential (ORP), while the outputs were electrolysis timing and liquid quality. A combination of trapezoid and triangle membership functions were used to describe the inputs and outputs. The rules were developed based on chemists' criteria, such as the electrolysis stopped at pH 5 and the safe quality is -100 to -80 mV ORP. The simulation result shows that the FL system can simultaneously conduct both processes without being disturbed by the other input. For instance, the electrolysis timing was affected by pH data only, and liquid quality was only affected by ORP. In the future, the MODIS prototype should facilitate the FL system's needs to enable real-time monitoring based on IoT, such as by having pH and ORP sensors that can withstand the electrolysis process.