Temperature and Humidity Controller for Infant Incubator

Infant incubator provides a controlled environment for newborns needing special care, such as those born prematurely. By placing an infant in an incubator,doctors and nurses can set and monitor different aspects of the child’s environment in order to create ideal conditions for survival and moreover it protect infants from pollutants and infection. Infant incubators and other advances in medical technology have made it possible for small or premature babies to survive.
The microcontroller AT89S52 based system keeps on monitoring the temperature of the baby and the chamber to a predetermined values, also the humidity is kept under control.

Block Diagram

About Humidity sensor

The humidity sensor used in this project is SY-HS-220, it provides analog dc output as per the humidity.
The following table provide the humidity with respect to out dc voltage.

The output of the Humidity sensor is fed to a ADC0804.

Temperature sensor

DS1820 is used here to measure the temperature. its a 1wire temperature sensor. It have inbuilt ADC. 

Circuit Diagram

Operation:

There are 3 switches (Mode, Increment, Decrement). The system continuously displays the Humidity, body temperature, water Chamber temperature on the lcd display. 

If the incubator goes hot above the predefined value then the fan is switched ON.
If the incubator temperature goes very cold then the Bulb is switched ON.
If the humidity is increased then the Water heater is switched ON until the temperature reaches the desired value.

All the values can changed at any time and they are stored in the EEPROM chip.