At Maker Faire Milwaukee this past weekend, [basement tech] was showing off his latest build, a PID controlled charcoal grill. While it hasn’t QUITE been tested yet with real food, it does work in theory.
PID (a feedback loop with some fancy math used to adjust the input to get a consistent output) controlled cooking is commonly used for sous vide, where one heats up a water bath to a controlled temperature to cook food in plastic bags. Maintaining water temperature is fairly easy. Controlling a charcoal barbecue is much more difficult. [basement tech] accomplishes this with controlled venting and fans. With the charcoal hot and the lid on, there are two ways to control temperature; venting to let hot air out, and blowing air on the coals to make them hotter. A thermocouple sensor stuck through the grill gives the reading of the air inside, and an Arduino nearby reads that and adjusts the vents and fans accordingly.
The video goes into extensive detail on the project, and describes some of the challenges he had along the way, such as preventing the electronics and servos from melting.
There’s not a lot of time left in the grilling season, so we hope [basement tech] gets an opportunity to enjoy the meats of his labor. Maybe he can trade food with [Jason] and his PID controlled meat smoker.
Nice, I’m on the way to doing the same to control a metal melting furnace :)
Maybe my version will be more easy to develop, check it here
https://github.com/abuharsky/BBQer
PID control assumes roughly constant available power, but charcoal is being used up and added, so it changes all the time. Stability/accuracy tradeoff might be an issue here.
Nope, as long as available power is more than required and can be throttled down, pid will work. Here it will stop working only when coal is almost missing, because blowing air on coal will give plenty of temperature.
Will work fine if you have the right hysteresis.
Also you usually use these controllers to monitor/control long-jobs.
That means you fill an “almost” airtight BBQ with a good amount of coal, light the coal and then close the whole thing.
The meat and inner BBQ get a K-type sensor each and thats what the PID then works with to calculate air-inlet.
We use this all the time – super simple to keep your BBQ at 100°C or at 300°C – or ramp it according to your specs.
Not much time left in the grilling season??? Amature….
Why? If you have a house with a veranda and some roof…
Then it’s BBQ season all year round.
If I can keep the fire lit, it’s grillin’ time!
When I lived in New England I would grill during the middle of January during the middle of a severe snow storm. No roof. As long as the fire is lit, the grill is a viable option.
Well in North Dakota it is hard to keep the grill at temp when it is -40 with a 15 m/h wind… So January/February isn’t really an option… So yeah only a few more months of grilling season…
My wife has plenty of videos of me on our patio, grilling/BBQing in varying depths of snow when we lived 20 miles from the Canadian border. We were approximately 125 miles further north than Buffalo, NY (We were about 300 miles northeast). This or something very similar would have been absolutely wonderful. Plus, my wife wouldn’t have all that video footage as evidence if she ever wants to have me committed.
BBQ Guru has a range of these and they are awesome
https://www.bbqguru.com/storenav?CategoryId=1&ProductId=34
Of cause there is readymade units – they are called “pit masters”
But rolling your own is a good practice and surely not the most useless thing to build.
These little gadgets make a 18hr slow-low-BBQ real easy if you have a decent firepit to control.
There are many commercial units that do the same thing… http://www.smobot.com is the one I own. Great job on this project, can’t wait to see your results. I hope you do a follow-on with some info on the stability.
Charcoal-powered reflow oven? ;)
I’ll throw in a shout out to the HeaterMeter:
https://github.com/CapnBry/HeaterMeter/wiki
I built one of those a few years ago and have been using it with my kamado style grill to great success ever since.
I was coming in here to say the same thing, I just build mine and I love it! Easily the best device for such a job.
Auber instruments makes a greatpid controller. AND they sell fans and thermoprobes separately.
Hi all … Daniel at basement tech here :-)
Thanks for all of your thoughts and comments.
Definitely the case here that “it’s all about the journey”.
Watch for progress and implementation of new ideas
from the Faire at the basement tech YouTube channel.
… sometimes also on the basement_tech twitch channel too.