Tune Your PID Controller

Buddy of mine did his master thesis as at a biofuel company a decade ago or so. He was supposed to do some advanced filter modelling, but do so he needed to configure the pid regulators to actually save the sensor values, not to mention turn them on. So he ran the pid configuration software, noticed they hadnt been tuned at all, set the values to something not catastrophically shit by just looking at the signals for a few minutes, then collected his data the next few days and went home to work on the thesis. It took a month before they figured out the random thesis worker no one paid attention too was the reason output was up 80%. He got a really nice bonus and job offer as a result. Then he actually tuned the pids using basic but proper system identification, but the largest gain is always from the most basic stuff, like turning the controllers on.

I would have killed for stuff like this back in university.<p>We had written some code in an early version of matlab in the labs that implemented the complex math but few of the students actually understood in depth what was going on and why. Everyone else remained puzzled even after the exams.<p>I went to work in Automotive, implementing various control algos for EVs motor control and later in motorsport and finally managed to understand all the math behind the magic and to mentally visualize the impact and results even before the simulations were run :) Good times

I wish this site expanded a little to model a few things present in most real world systems:<p>* Limits. Nearly all systems have a maximum and minimum input value. That should be modelled so behaviours when the limit is reached can be modelled. For example, a car has a top speed - and any further pressing of the accelerator will not make it go faster, but a PID loop will keep integrating any error, causing the system to not behave as expected.<p>* &#x27;Slack&#x2F;Hysterisis&#x27;<p>* Asymmetric systems - the force applied when pushing a system may not be the same as pulling.<p>I really want a system where data can be thrown in like this, and it fit a model to the data and suggest not only PID values, but other types of controller which would be a better fit.

Before I entered management, I spent about 15 years as an engineer building &quot;greenfield&quot; drug manufacturing sites using automation packages such as Allen-Bradley, Emerson DeltaV and Siemens. There is nothing more time consuming than trying to tune the hundreds of PID loops in these facilities not only during site acceptance testing of equipment, but also during validation. These companies try to offer PID packages but they were always really inadequate. I wouldve loved a tool like this.<p>One of my biggest mistakes was tuning a loop during the winter shutdown on a large scale vaccine reactor. It dramatically increased the cells growth rate to a point where we would have had to modify our drug application. Understandably, the regulatory people had me de-tune the loop.

I have a Lelit espresso machine with a PID and there are many forum discussions where people share their P, I, D values and argue which ones produce the best resuls. I haven&#x27;t really fiddled with those yet but maybe I should give the article a try.

Developer here, ask me anything (wondered why the traffic exploded today until I opened HN).

I have used this tool to tune the water level PIDs of several hydroelectric substations. I passed from spending days with manual fine tuning to a couple of hours of a simple experiment and tuning with this tool.

Needs integration with Betaflight&#x2F;INAV logs.<p>I&#x27;d happily pay for that. Tuning PIDs is tedious and takes away from flying.

PID controllers are so fun. I experimented with using them to animate tentacles for a game I&#x27;m working on. They&#x27;re great for all sorts of controllers in fiddly physics based systems.<p>(<a href="https:&#x2F;&#x2F;twitter.com&#x2F;LeapJosh&#x2F;status&#x2F;1327051175112421377" rel="nofollow">https:&#x2F;&#x2F;twitter.com&#x2F;LeapJosh&#x2F;status&#x2F;1327051175112421377</a>)<p>Judging by some of the posts in this thread, it amuses me that I might have a leg up in the oil and gas industry.

Woah this is cool! I recently made a little sim for a gimballed rocket that uses a PID loop. It&#x27;s really helped me tune my real rocket and get some good results:<p><a href="https:&#x2F;&#x2F;codesandbox.io&#x2F;s&#x2F;rocket-sim-final-with-position-control-0oq6u" rel="nofollow">https:&#x2F;&#x2F;codesandbox.io&#x2F;s&#x2F;rocket-sim-final-with-position-cont...</a>

The math behind this is linear control theory (LCT) [0], which is quite interesting. LCT and the Laplace transform techniques at its heart (this is where the &quot;s&quot; terms on the web site come from) are not really that daunting and once you learn them you&#x27;ll know <i>whether you even need</i> the I and D parts of the PID and what order of each you need.<p>If we had an analogous &quot;Machine Learning Theory&quot;, we&#x27;d be able to predict from first principles how many neurons we needed, how many hidden layers we needed, and what architecture (i.e. recursive, convolutional, etc.) we needed to solve a given problem. We don&#x27;t have that now, but I hope we do some day. The good news is we do have such a theory for control problems (at least the linear ones).<p>[0] <a href="https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Control_theory" rel="nofollow">https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Control_theory</a>

Odd. From my perspective, there is no &quot;perfect&quot; PID tuning, so this function is confusing. I fly drones, and I adjust the PID tunings depending on how I&#x27;m flying: acrobatics, racing, filming, instruction, etc. Is there a function to tune the tuner? :) What I mean is: changing P impacts responsiveness to the transmitter controls, D affects wind gusts and sudden changes (fast loops anyone?), I is more for racing, its a bit more complex than that but you get the gist. Why pick one set?<p>EDIT: (a) I didn&#x27;t actually use the Webapp, after using it, there&#x27;s more to it than my oversimplification. (b) I&#x27;m referring to the rates, not the PIDs. Thanks to the folks below (&#x27;pdituner&#x27; and &#x27;somehnguy&#x27;).

It would be cool if there was like &quot;quick tips&quot; for how to get this data out of various PID&#x27;y things. For example how do I get data out of Marlin (3d printer controller) to tune my hotends?

It is neither efficient nor optimal and could even be unsafe, but the most <i>fun</i> way to optimize your PID controller is on the actual plant with iterative parameter search.<p>Watch your device whirr and attempt to jump off your table as your algorithm is trying to optimize the P factor! Quickly estimate how good the fit is just by looking at the actuator!<p>(Disclaimer: think hard about safety before doing this, and make sure your device is strong enough or your motor is weak enough to ensure that no parts will be flying into people)

I was actually kinda hoping for a game where you could fiddle with dials and tune a toy simulation

What code implementations of PID controlling do you know, to learn or base upon, to build an actual solution?<p>I&#x27;ve successfully used this blog post series from 2011, which covers the principles behind a PID library for Arduino:<p><a href="http:&#x2F;&#x2F;brettbeauregard.com&#x2F;blog&#x2F;2011&#x2F;04&#x2F;improving-the-beginners-pid-introduction&#x2F;" rel="nofollow">http:&#x2F;&#x2F;brettbeauregard.com&#x2F;blog&#x2F;2011&#x2F;04&#x2F;improving-the-beginn...</a>

Oh man. I wish I had the pages of manual PID tuning notes from when I was doing work with autonomous quadrotors in university to show what this thing replaces. Something like this would have saved me a massive amount of time, thanks for making it and thanks especially for wrapping it up into a nice interface.

A decent Python implementation of a PID loop controller is available here: <a href="https:&#x2F;&#x2F;github.com&#x2F;pjkundert&#x2F;ownercredit" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;pjkundert&#x2F;ownercredit</a>

I have an old commercial electric bakery oven with simple a simple 1 to 10 dial. I have looked into upgrading it to a digital thermostat with a PID, but have never figured out how I would set up the PID. This looks like a great resource.

Perfect timing! Just last night I picked up a half-done hobby project to write a fan controller for some of my server hardware, starting by reacquainting myself with PID theory. This&#x27;ll be a great help, thanks!

Might be useful for my megasquirt corrections if I figure out how to use it. Maybe I’ll get that OEM idle again

This can help setting up a thermostat, which is super annoying to do if you’re not used to it

If only the site explained wtf a PID controller was ...