I just built an electric chamber for the sole purpose of implementing PID Control. What settings did you end up with that gave you such nice control at charge? So far I'm having it bounce back and forth a lot and it eventually stabilizes as the roast develops.

Good day and merry Christmas! My settings and how to charge are in the previous two posts. I haven't changed anything since then. Perhaps the only detail to make more more clear, at least on my roaster, ensure the SV curve begins lower than your charge temp. Best wishes on your journey and happy to help! Have a great day

Prototype completed this weekend and 3d printed. Still a few things to work out but liking the way it looks so far. The Servo mount attaches to the roaster control plate via magnet. The 3-e control plate is aluminum which of course isn't ferrous. I have a neodymium magnet lightly glued to the bottom of the plate and one glued in a recess of the red servo mount. Works very well and makes the servo mount easy to remove then self-centers when it's reattached. One goal I had was to not change the machine from stock. This is as close as I could get. There are a couple other designs that would achieve it without the magnet on the bottom but I like how clean this is.

Lesson learned today and a tip on flick and crash mitigation. Always verify your PID Settings before roasting. Upgraded to Artisan-Scope 2.4.4 recently and I'm unsure if the reset happened then or something I did. No matter, no harm done and good lesson learned. 2 roasts of 1lb Tanzania Peaberry in my Artisan 3-e with Artisan-Scope PID control. (thought I'd take my 3d printed servo mount prototype for a spin). First picture is obviously a horror show. Thought I'd share it in all its fail-tastic glory. I knew something was wrong early in the roast with the initial high charge heat spike but didn't know why, after some looking, apparently the Artisan-Scope Software PID had reset to its default of .66,0,0 when I need a 2.5,0.01,65 for the 3e and my prototype. Right around 9 minutes I made the change and you can see it try to "help" but it was too late. Then concerned I wouldn't hit 2C, I had to goose the throttle. The second photo is money though, I'm super happy with the prototype and Artisan-Scope Software PID performance properly tuned. Notice on the second roast, there is no flick and crash. The trick is to have your roast be slightly below the SV curve so the roaster/PID is "on power" during 1C. I learned that from big daddy Dan Lawrence. (hat tip good sir)

Fail-tastic default PID settings Roast -




PID Corrected = Fantastic!

What an incredible thread, and I can't believe I'm just now seeing this! I literally just posted a video YESTERDAY about how to use an RC servo with Artisan software/roaster, but using Phidgets! I even mention it in my video, but PID is my next step. Your 3d printed parts look amazing! Much better than my hand-ground steel parts.
Question for you, Lexingtonian. You say the trick to avoiding the Rao crash and flick is to have the BT just a bit BELOW the SV curve so that it's "on the heat". I understand WHY you'd want to do this, but HOW do you get your BT below the SV curve at 1C? Doesn't PID kind of take over the controls, so to speak, so that you're at the mercy of the universe on whether you happen to be a tick above or below the SV curve? I'm just not sure how you're ensuring that you're slightly below the curve at 1C (I hope my question makes sense.)

For fun, this was the video that I made on my Phidget version of what you've done. Also, someone else mentioned this when you were first setting up your servo, but I can confirm that you can, indeed, use a negative offset on a single slider to get values that are both positive and negative. I did it on my previous roaster. But you're up and running so that's water under the bridge at this point. Again, WELL DONE, and thank you for sharing this!

Jscott it was great to speak to you over the weekend. I'm looking forward to where this goes I think it opens up a whole new level of value for the Coffee Crafters roaster. Thanks for the collaboration and information sharing back-and-forth and also doing it with phidgets so I didn't have to! Hopefully when we get all of our testing done we can come up with a central place to keep the information so that it's locatable for others that want to replicate it. I'm also hoping to offer 3-D printed parts, bill of materials and plans for folks that want to do the same thing. That would work with the phidgets as well. Thanks for sharing! Keep it coming!

If anyone has questions please post. I'm sure we're both happy to answer!

Great information herein gents! Thanks for your efforts!

I sort of wanted to put a bow on the thread and thank a few people.

As of this writing my PID Settings are 4,.02,85 for my Coffee Crafters Artisan 3-e with zero look ahead and the setup is a treat to use. The Yocto devices are electrically isolated, are extremely predictable with very little smoothing. I've seen no electrical spikes with Yocto that others get with Phidgets and K-Type ThermoCouples (I'm not down on Phidgets at all, if you have it already, certainly use it - it works well). I've added more videos on YouTube and details in a couple of Facebook Forums if so inclined (FB Group - Fluid Bed Coffee Roasters Forum and Artisan 3-e / 2.5 Roaster Forum). I even made an updated Loft Control Knob to give a little finer control over the sensitive loft pot. You can message me here or shoot me an email at Bryan@StellarBeans.Coffee if you like.

BIG Thank you to:
- Ken Lathrop at CoffeeCrafters.com for an elegantly simple fluid-bed coffee roasting system!
- MaKoMo here on the HB Forum and thew wizards at Artisan-Scope.org for creating an incredible software stack for software PID roasting!
- Dan Lawrence in the Fluid Bed Coffee Roasters Forum (FaceBook) for incredible engagement in getting the PID dialed in!
- Jason Scott with Hermetheus Coffee for filling in the gaps on PID control, Artisan-Scope settings and great camaraderie!
- YoctoPuce for knowing exactly what we needed!

Here's where it ended up. I run my setup on the equivalent of a Raspberry Pi (ARM based SBC). I use a Yocto-Servo and Yocto-Thermocouple to control the servo for heat and graph the thermocouple for Bean Temp and I VNC into the SBC to control the roast from my iPad (most of the time).




Thanks for reading!

Thank you for all your effort and posting this Bryan.

I am seriously considering getting the 3e and your work here has me even more excited about the possibilities.

Mike

The artisan roaster uses 1 or two SSR connected to that knob, doesn't it?

Why not use the PID control of a logic level control directly to the SSR compared to servomotors' control?

That would require less hardware and possibly smooth the element heat variability more, wouldn't it?