0.1.6 PID_RT

libraries/PID_RT/.github/workflows/arduino-lint.yml

@@ -6,7 +6,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - uses: arduino/arduino-lint-action@v1
         with:
           library-manager: update

libraries/PID_RT/.github/workflows/arduino_test_runner.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: 2.6

libraries/PID_RT/.github/workflows/jsoncheck.yml

@@ -10,7 +10,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: json-syntax-check
         uses: limitusus/json-syntax-check@v1
         with:

libraries/PID_RT/CHANGELOG.md

@@ -6,12 +6,18 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 
+## [0.1.6] - 2023-02-12
+- add example **PID_simulated_heater.ino** Kudos to drf5n
+- update readme.md
+- update GitHub actions
+- update license 2023
+
+
 ## [0.1.5] - 2022-10-23
 - add RP2040 to build-CI
 - add changelog.md
 - minor edits readme.md
 
-
 ## [0.1.4] - 2021-12-23
 - update library.json, license, 
 - minor edits

libraries/PID_RT/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2020-2022 Rob Tillaart
+Copyright (c) 2020-2023 Rob Tillaart
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

libraries/PID_RT/PID_RT.cpp

@@ -1,7 +1,7 @@
 //
 //    FILE: PID_RT.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.5
+// VERSION: 0.1.6
 // PURPOSE: PID library for Arduino
 //     URL: https://github.com/RobTillaart/PID
 

libraries/PID_RT/PID_RT.h

@@ -2,7 +2,7 @@
 //
 //    FILE: PID_RT.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.5
+// VERSION: 0.1.6
 // PURPOSE: PID library for Arduino
 //     URL: https://github.com/RobTillaart/PID_RT
 
@@ -10,7 +10,7 @@
 #include "Arduino.h"
 
 
-#define PID_LIB_VERSION               (F("0.1.5"))
+#define PID_LIB_VERSION               (F("0.1.6"))
 
 
 class PID_RT
@@ -64,7 +64,7 @@ public:
 
 
   //  set Proportional on Input or on Error
-  void setPropOnInput() { _POI = true; };      // default
+  void setPropOnInput() { _POI = true; };      //  default
   void setPropOnError() { _POI = false; };
   bool isPropOnInput()  { return _POI == true; };
   bool isPropOnError()  { return _POI == false; };

libraries/PID_RT/README.md

@@ -15,9 +15,29 @@ Arduino library for PID controller.
 
 The PID_RT class allows the user to instantiate a PID controller.
 
+This library allows one to 
+- adjust the K parameters runtime.
+- stop / start computing runtime.
+
+(to be elaborated)
+
+
+#### Some PID background
+
+- https://en.wikipedia.org/wiki/PID_controller
+- https://www.ni.com/nl-nl/innovations/white-papers/06/pid-theory-explained.html
+- https://www.youtube.com/watch?v=wkfEZmsQqiA
+
+E-book
+- https://www.elektor.nl/pid-based-practical-digital-control-with-raspberry-pi-and-arduino-uno-e-book
+
 
 ## Interface
 
+```cpp
+#include "PID_RT.h"
+```
+
 ### Constructor
 
 - **PID_RT()** minimal constructor.
@@ -26,14 +46,14 @@ The PID_RT class allows the user to instantiate a PID controller.
 
 ### Core
 
-- **void reset()** resets internals to startup.
-- **void setPoint(float sp)** sets setPoint, that needs to be reached.
-- **float getSetPoint()** read back setPoint.
-- **bool  compute(float input)** does one iteration of the PID controller. 
-Returns **true** after calculation. 
+- **void reset()** resets internals to startup (Kp == Ki == Kd == 0).
+- **void setPoint(float sp)** sets the setPoint, that needs to be reached.
+- **float getSetPoint()** read back the setPoint.
+- **bool compute(float input)** does one iteration of the PID controller. 
+Returns **true** after a calculation is done. 
 Returns **false** if not computed, either due to stop flag or not yet time to do the calculation.
 - **float getOutput()** get the last calculated output value. 
-- **bool  setK(float Kp, float Ki, float Kd)** Set the initial P I D parameters as a group.
+- **bool setK(float Kp, float Ki, float Kd)** Set the initial **P I D** parameters as a group.
 Overwrites the values set in the constructor.
 
 
@@ -86,25 +106,30 @@ almost sure that no iterations are missed.
 
 ## Operations
 
-See examples.
+See examples and 
+- https://wokwi.com/projects/356437164264235009  (thanks to drf5n)
 
 
 ## Future
 
-#### must
+#### Must
 
 - update / improve documentation
 - more testing
 
-#### should
 
-- add examples to test more
-- improve unit test
-- move all code to .cpp
+#### Should
 
-#### could
-
-- add reference to PID book / website?
 - investigate if it works as PI or P controller too.
   - PI as derived or base class?
+- add examples to test more
+- improve unit test
 
+
+#### Could
+
+- add reference to PID book / website?
+- move all code to .cpp
+
+
+#### Wont

libraries/PID_RT/examples/PID_simulated_heater/.arduino-ci.yml

@@ -0,0 +1,27 @@
+platforms:
+  rpipico:
+    board: rp2040:rp2040:rpipico
+    package: rp2040:rp2040
+    gcc:
+      features:
+      defines:
+        - ARDUINO_ARCH_RP2040
+      warnings:
+      flags:
+
+packages:
+  rp2040:rp2040:
+    url: https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
+
+compile:
+  # Choosing to run compilation tests on 2 different Arduino platforms
+  platforms:
+    - uno
+    # - due
+    # - zero
+    # - leonardo
+    - m4
+    - esp32
+    # - esp8266
+    # - mega2560
+    - rpipico

libraries/PID_RT/examples/PID_simulated_heater/PID_simulated_heater.ino

@@ -0,0 +1,93 @@
+//
+//    FILE: PID_simulated_heater.ino
+//  AUTHOR: drf5n  (based on basic example)
+// PURPOSE: demo
+//
+//  This simulates a 20W heater block driven by the PID
+//  Wokwi https://wokwi.com/projects/356437164264235009
+//
+//  https://github.com/RobTillaart/PID_RT/issues/5
+
+
+#include "PID_RT.h"
+
+PID_RT PID;
+
+const int PWM_PIN = 3;  // UNO PWM pin
+
+int op = 0;
+float input = 0;
+
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println(__FILE__);
+
+  PID.setPoint(125);
+  PID.setOutputRange(0, 255);   //  PWM range
+  PID.setInterval(50);
+  PID.setK(2, 5, 1);
+  PID.start();
+
+  op = analogRead(A0);
+}
+
+
+void loop()
+{
+  float heaterWatts = ((int)op)*20.0/255;   //  20W heater
+  float blockTemp = simPlant(heaterWatts);  //  simulate heating
+  input = blockTemp;
+  //  input = analogRead(A0);
+  if (PID.compute(input))
+  {
+    op = PID.getOutput();
+    analogWrite(PWM_PIN, op);
+
+  //  Serial.print(PID.getInput());
+  //  Serial.print('\t');
+  //  Serial.println(op);
+  }
+  report();
+}
+
+
+void report(void){
+  static uint32_t last = 0;
+  const int interval = 1000;
+  if (millis() - last > interval){
+    last += interval;
+//    Serial.print(millis()/1000.0);
+    Serial.print(PID.getSetPoint());
+    Serial.print(' ');
+    Serial.print(input);
+    Serial.print(' ');
+    Serial.println(op);
+  }
+}
+
+float simPlant(float Q){ // heat input in W (or J/s)
+   //  simulate a 1x1x2cm aluminum block with a heater and passive ambient cooling
+   //  next line "C is not used", fails in arduino-build-ci for ESP32
+   //  float C = 237;  // W/mK thermal conduction coefficient for Al
+   float h    = 5;    //  W/m2K thermal convection coefficient for Al passive
+   float Cps  = 0.89; //  J/g°C
+   float area = 1e-4; //  m2 area for convection
+   float mass = 10;   // g
+   float Tamb = 25;   // °C
+
+   static float T       = Tamb;   //   °C
+   static uint32_t last = 0;      //  last call
+   uint32_t interval    = 100;    //  milliseconds
+
+   if(millis() - last >= interval){
+     last += interval;
+     T = T + Q * interval / 1000 / mass / Cps - (T - Tamb) * area * h;
+   }
+   return T;
+}
+
+
+//  -- END OF FILE --
+

libraries/PID_RT/library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/PID_RT"
   },
-  "version": "0.1.5",
+  "version": "0.1.6",
   "license": "MIT",
   "frameworks": "arduino",
   "platforms": "*",

libraries/PID_RT/library.properties

@@ -1,5 +1,5 @@
 name=PID_RT
-version=0.1.5
+version=0.1.6
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino PID library

libraries/PID_RT/test/unit_test_001.cpp

@@ -103,4 +103,5 @@ unittest(test_compute)
 unittest_main()
 
 
-// --------
+//  -- END OF FILE --
+