Prototyping a closed loop control system for a neonatal incubator

Abstract

Premature born neonates often need special cares because some vital organs, biochemical or enzyme systems may not have developed su ciently, with the results that the infant is unlikely to survive undamaged without special protection. Depending on culture and on geographic location, either thermal contact with the mother or thermal insulation has been a major form of protection for many centuries. The purpose of this study has been to design and implement a closed loop control system to regulate the temperature inside a neonatal incubator. This closed loop control system has been designed using the software in the loop technique, which minimizes the hardware related work and concentrates all the decision- making in the software. The closed loop implemented is a combination of sensing devices and actuators that operate synchronously to provide a stable thermal environment inside the incubator. The sensing devices are ve resistance temperature detectors placed following the IEC-60601 standards, two current sensors, which give feedback information about the power consumption of the actuators, and two disturbance sensors that provide information about the opening of the incubator clappers. The actuators, which produce the stable environment inside the incubator, are the heater and the motor that propels the fan. Results con rm that the closed loop control system has been successfully implemented and the software designed is able to maintain a stable temperature inside the incubator. Moreover, the prototype implemented allows continuing the task started with this work, with further optimization and improvement of the controller.