Incubator
The incubator is a big 60x40x35cm Styrofoam box. Inside is the egg turning machine and the 150 Watt heating element. For better heat and air circulation, I use a 8x8cm 12V PC-fan. To provide the optimal humidity, I simply use plastic trays and "tune" the humidity levels by the available water surface. The warm air flows over the water and humidifies the air.
Although not fully needed, I decided to have constant fresh air supply and added a 3cm hole next to the heater on the lower side of the box. On the opposite side there is an outflow on the top end of the box. This way the fan pulls fresh air, heats it up and used air can leave the box on the other side. The heater is strong enough to keep up temperature levels anyways.
Humidity & Temperature is constantly measured with two DHT-22 sensors. Temperature is then adjusted automatically via a PID controlled heater using PWM in combination with a MOSFET.
Incubator with lid removed. Red arrow shows the air flow. Green circles show the position of the DHT-22 sensors. Blue is the power supply (old salvaged PC part). The 12V power the controller (yellow) and the heater.
Incubator when closed
The lid contains another lid with a plexiglass barrier. This way one can have a look inside without removing the entire lid.