🌸 PetalPID

Lightweight universal PID controller library with Ziegler–Nichols auto tuning and variable cycle time

Perfect PID for your project

PetalPID is a floating-point based PID library that can be used on Arduino as well as on any other platform. Even in regular C++ code (it is possible to convert it to pure C). Unlike other libraries, PetalPID uses variable cycle time and the same function for the main and tuning loop, making it very easy to implement.

🚧 This's not the release version of PetalPID! Please be careful!

🏗️ Getting started

Example of auto-tuning process (this graph is produced by examples/TemperatureController)

1. Download or include this repo as a library

   Example for PlatformIO:

   lib_deps =
       https://github.com/F33RNI/PetalPID.git
   

2. Include header file in your project

   #include <PetalPID.h>
   

3. Create PetalPID instance

   PetalPID pid = PetalPID();
   
   // Or
   PetalPID pid = PetalPID(1.f, 2.f, 3.f, 0.f, 255.f);
   

4. Setup limits and gains (if you're not starting with auto-tune)

   pid.set_min_max_output(0.f, 255.f);
   pid.set_min_max_integral(-1000.f, 1000.f);
   
   pid.set_gains(1.f, 2.f, 3.f);
   

5. In a main loop...

   // Without any delays. Call as frequent as possible
   float pid_output = pid.calculate(measured_value, setpoint, micros());
   

6. Starting auto-tuning

   // TYPE_P, TYPE_PI, TYPE_PD, TYPE_CLASSIC_PID, TYPE_PESSEN_INTEGRAL_RULE, TYPE_SOME_OVERSHOOT, TYPE_NO_OVERSHOOT
   // 50 on-off cycles
   pid.start_auto_tune(TYPE_NO_OVERSHOOT, 50);
   

7. Getting results

   Serial.print(pid.get_p());
   Serial.print("\t");
   Serial.print(pid.get_i());
   Serial.print("\t");
   Serial.println(pid.get_d());
   

More info in 📄 Documentation section and examples/

📄 Documentation

You can build Doxygen documentation using provided Doxygen file

Just clone repo and run:

doxygen

This will generate HTML and LaTeX docs. Open docs/index.html file to view it

💡 Projects using PetalPID

• in17clock by Fern Lane

  IN17 Nixie tube clock with internal DC-DC converter, random melody alarm and temperature/humidity sensor

• ilet-103-motor-controller be Fern Lane

  Digital speed controller for ILET 103 reel-to-reel deck

Does your project also use PetalPID? Add it to this list by creating a pull request or issue!

✨ Contribution

1. Clone this repo

git clone https://github.com/F33RNI/PetalPID

2. Follow the .clang-format style while editing the code
3. Follow Conventional Commits while creating commits
4. Create pull request