This week we worked for the first time on the PID function.
For the temperature regulation we use the PID library by Brett Beauregard.
From Wikipedia: “A PID controller calculates an ‘error’ value as the difference between a measured [Input] and a desired setpoint. The controller attempts to minimize the error by adjusting [an Output].”
So, the input come from our heat sensor (DS18S20), for the setpoint we use a potentiometer, and the output is a solid state relay.
The main difficulty is to find the right parameters for the PID. There are 3 Tuning Parameters: Kp, Ki & Kd. We have to do some tests, for now, the best results were with:
For the moment, we are going to use these data because it works well even if the user has to wait enough time for the soup would be hot.
We are happy because we slowly see the end of our project!
BERTRAND, DEPARIS, LATOUR, THOMAERE, VAN DEN BOSSCHE.