Design of a Microcontroller-Based Neonatal Incubator Temperature Controller for Teaching Hospitals in Oyo State

Neonatal hypothermia is a leading cause of neonatal mortality in Nigeria, and temperature control failures in incubators used in teaching hospital special care baby units contribute significantly to preventable deaths. This study designs a microcontroller-based temperature controller circuit as a retrofit upgrade for neonatal incubators in use at teaching hospitals in Oyo State, specifically targeting units with non-functional or imprecise temperature regulation systems. The controller was designed using an Arduino Mega microcontroller, a DS18B20 digital temperature sensor for precision ambient temperature measurement inside the incubator chamber, a proportional-integral-derivative control algorithm for precise heating element regulation, a 16x2 LCD display for real-time temperature display, and an audible alarm for out-of-range temperature alerts. The system was programmed to maintain the incubator chamber temperature within the standard neonatal thermoneutral range of 32 to 36 degrees Celsius with a measured accuracy of plus or minus 0.3 degrees Celsius under simulated load conditions. Power failure protection was incorporated through a battery backup module capable of sustaining operation for ninety minutes. Performance testing was conducted on a simulated incubator chamber over seventy-two hours at the University of Ibadan Engineering workshop, demonstrating stable temperature maintenance within the target range. The study identifies connector compatibility, electromagnetic interference from ward equipment, and sterilization of external sensor components as engineering challenges requiring resolution before clinical deployment. Regulatory approval through NAFDAC and collaboration with the University College Hospital biomedical department are recommended as next steps. Keywords: neonatal incubator, temperature controller, PID algorithm, special care baby unit, Oyo State.