New Open Source Arduino Based PID Controller Released

I've been playing with the Arduino PID Library for my brewery control platform on and off the past few months. The PID Library author Brett Beauregard has just released his new Open Source (Code, Hardware, Design) PID Controller that functions just like all the other black box PID controllers you can buy. However, since this is based on the Arduino, it's fully hackable. I thought some of you might want to check it out.

New in this version is an Auto-Tune feature that should take some of the guess work out of setting the P I and D parameters.

One area that I see right away where it is lacking is no support for RTDs. Same issue with BrewTroller and BCS.

I do like that is it hackable, but that is still a sticking point for me.

Check out this video.
[ame=http://www.youtube.com/watch?v=n768MXEESUo&feature=player_embedded]osPID - Hacking - YouTube[/ame]

He says they are working on expansion cards that allow for different interfaces. Maybe RTDs would be possible. Personally, I like the Dallas digital sensors because they are super easy to interface. Drop them in a thermowell and you are good to go.

Hi all, saw the track-back on my blog and figured I would post a quick reply. RTD Card is definitely in the pipeline, sooner rather than later.

Brett, that's great news. Thanks for all your work on this project! Have you posted that auto-tune code yet?

br3ttb said:

Hi all, saw the track-back on my blog and figured I would post a quick reply. RTD Card is definitely in the pipeline, sooner rather than later.

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i was just about to post- you can certainly use RTDs with arduino. not sure if there is already a nice library to do it, but its just a resistance measurement. it can be done quickly with only the sensor and a few resistors, or more accurately by making a simple wheatstone bridge, and using an op-amp and some math.

The Auto-Tune Library source has been released if you want to play with it:
https://github.com/br3ttb/Arduino-PID-AutoTune-Library

And here's the Front End source code that runs in Processing on your computer:
https://github.com/osPID/osPID-Front-End

br3ttb said:

Hi all, saw the track-back on my blog and figured I would post a quick reply. RTD Card is definitely in the pipeline, sooner rather than later.

Click to expand...

What's the status on the RTD card and/or support for RTD through other digital/analog ports on the arduino ?

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