how to write PID control algorithm to control temperature

[_bhum]

i am working on project which is monitoring and controlling the temperature and humidity inside a chamber using raspberry pi and HTU21D sensor. i am very new on qt please help me coding.

[koahnig]

@_bhum

Hi and welcome to devnet forum

You need to cross-compile Qt libraries for raspberry pi https://www.raspberrypi.org/forums/viewtopic.php?t=204778 or to find an already compiled version. However, I would recommend to do the cross-compilation yourself, because you willknow what you have done when running into issues.

Furthermore, it is a good recommendation to install Qt creator and Qt libs on a desktop.

When you are stuck with specific Qt issues, there are a lot of people in the forum being to offer advice and assistance.

[_bhum]

@koahnig Thanks. but the problem is that i dont know how to implement a controller algorithm on qt

[JKSH]

@_bhum said in how to write PID control algorithm to control temperature:

the problem is that i dont know how to implement a controller algorithm on qt

It's the same way you implement a controller algorithm in C/C++.

Do you know how to do that?

[Pablo J. Rogina]

@_bhum said in how to write PID control algorithm to control temperature:

i dont know how to implement a controller algorithm on qt

so questions you may ask yourself:

1. Why I'm gonna use Qt to implement a PID control algorithm?
2. Am I able to implement a PID control algorithm with C++?

If answer to #2 is yes, then it implies #1 yes.

What I see here is that you'll be using Qt to make a fancy UI to let the user know about the status of the chamber under control, so he/she can set thresholds for temperature and humidity with nice UI controls/displays.

[_bhum]

@Pablo-J.-Rogina said in how to write PID control algorithm to control temperature:

@_bhum said in how to write PID control algorithm to control temperature:

i dont know how to implement a controller algorithm on qt

so questions you may ask yourself:

1. Why I'm gonna use Qt to implement a PID control algorithm?
2. Am I able to implement a PID control algorithm with C++?

If answer to #2 is yes, then it implies #1 yes.

What I see here is that you'll be using Qt to make a fancy UI to let the user know about the status of the chamber under control, so he/she can set thresholds for temperature and humidity with nice UI controls/displays.

Thanks for your reply, by keeping the above questions in mind I've started coding.

[_bhum]

how i execute my program on raspi terminal????

[koahnig]

@_bhum

You need to use a terminal program such as putty on your desktop. For details on how check out the raspberry pi webpage.

[Pablo J. Rogina]

@_bhum said in how to write PID control algorithm to control temperature:

how i execute my program on raspi terminal????

do you know how to run a program in a Linux terminal?