Diff: PID.h

Revision:

2:55bf0f813bb4

Parent:

1:117e0c36eb22

Child:

3:316f974b7f98

diff -r 117e0c36eb22 -r 55bf0f813bb4 PID.h
--- a/PID.h	Mon Jan 25 22:29:38 2016 +0000
+++ b/PID.h	Wed Jan 27 21:32:11 2016 +0000
@@ -1,72 +1,116 @@
-//#pragma once
-
+/**
+ * @author Aaron Berk
+ *
+ * @section LICENSE
+ *
+ * Copyright (c) 2010 ARM Limited
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @section DESCRIPTION
+ * 
+ * A PID controller is a widely used feedback controller commonly found in
+ * industry.
+ *
+ * This library is a port of Brett Beauregard's Arduino PID library:
+ *
+ *  http://www.arduino.cc/playground/Code/PIDLibrary
+ *
+ * The wikipedia article on PID controllers is a good place to start on
+ * understanding how they work:
+ *
+ *  http://en.wikipedia.org/wiki/PID_controller
+ *
+ * For a clear and elegant explanation of how to implement and tune a
+ * controller, the controlguru website by Douglas J. Cooper (who also happened
+ * to be Brett's controls professor) is an excellent reference:
+ *
+ *  http://www.controlguru.com/
+ */
+ 
 #ifndef PID_H
 #define PID_H
-
+ 
+/**
+ * Includes
+ */
+#include "mbed.h"
+ 
+/**
+ * Defines
+ */
 #define MANUAL_MODE 0
 #define AUTO_MODE   1
-
-class PID
-{
+ 
+/**
+ * Proportional-integral-derivative controller.
+ */
+class PID {
+ 
 public:
-
-    /*
-    * Constructor
-    * Sets default limits, calculates tuning parameters, and sets manual mode with no bias.
-    * @param Kc - Tuning parameter
-    * @param tauI - Tuning parameter
-    * @param tauD - Tuning parameter
-    * @param interval PID calculation performed every interval seconds.
-    */
+ 
+    /**
+     * Constructor.
+     *
+     * Sets default limits [0-3.3V], calculates tuning parameters, and sets
+     * manual mode with no bias.
+     *
+     * @param Kc - Tuning parameter
+     * @param tauI - Tuning parameter
+     * @param tauD - Tuning parameter
+     * @param interval PID calculation performed every interval seconds.
+     */
     PID(float Kc, float tauI, float tauD, float interval);
-
-    /*
-    * Scale from inputs to 0-100%.
-    * @param InMin The real world value corresponding to 0%.
-    * @param InMax The real world value corresponding to 100%.
-    */
-    void setInputLimits(float inMin, float inMax);
-
-    /*
-    * Scale from outputs to 0-100%.
-    * @param outMin The real world value corresponding to 0%.
-    * @param outMax The real world value corresponding to 100%.
-    */
+ 
+    /**
+     * Scale from inputs to 0-100%.
+     *
+     * @param InMin The real world value corresponding to 0%.
+     * @param InMax The real world value corresponding to 100%.
+     */
+    void setInputLimits(float inMin , float inMax);
+ 
+    /**
+     * Scale from outputs to 0-100%.
+     *
+     * @param outMin The real world value corresponding to 0%.
+     * @param outMax The real world value corresponding to 100%.
+     */
     void setOutputLimits(float outMin, float outMax);
-
-    /*
-    * Calculate PID constants.
-    * Allows parameters to be changed on the fly without ruining calculations.
-    * @param Kc - Tuning parameter
-    * @param tauI - Tuning parameter
-    * @param tauD - Tuning parameter
-    */
+ 
+    /**
+     * Calculate PID constants.
+     *
+     * Allows parameters to be changed on the fly without ruining calculations.
+     *
+     * @param Kc - Tuning parameter
+     * @param tauI - Tuning parameter
+     * @param tauD - Tuning parameter
+     */
     void setTunings(float Kc, float tauI, float tauD);
-
-    /*
-    * Reinitializes controller internals. Automatically
-    * called on a manual to auto transition.
-    */
+ 
+    /**
+     * Reinitializes controller internals. Automatically
+     * called on a manual to auto transition.
+     */
     void reset(void);
-
-    /*
-    * Set how fast the PID loop is run.
-    * @param interval PID calculation peformed every interval seconds.
-    */
-    void setInterval(float interval);
-
-    /*
-    * Set the target value for the PID loop to maintain.
-    * @param sp The target value to maintain.
-    */
-    void setSetPoint(float sp);
-
-    /*
-    * Set the target value for the PID loop to maintain.
-    * @param pv The target value to maintain.
-    */
-    void setProcessValue(float pv);
-
+    
     /**
      * Set PID to manual or auto mode.
      *
@@ -74,19 +118,42 @@
      *             Non-zero -> Auto
      */
     void setMode(int mode);
-
-    /*
-    * Set the bias.
-    * @param bias The bias for the controller output.
-    */
+    
+    /**
+     * Set how fast the PID loop is run.
+     *
+     * @param interval PID calculation peformed every interval seconds.
+     */
+    void setInterval(float interval);
+    
+    /**
+     * Set the set point.
+     *
+     * @param sp The set point as a real world value.
+     */
+    void setSetPoint(float sp);
+    
+    /**
+     * Set the process value.
+     *
+     * @param pv The process value as a real world value.
+     */
+    void setProcessValue(float pv);
+    
+    /**
+     * Set the bias.
+     *
+     * @param bias The bias for the controller output.
+     */
     void setBias(float bias);
-
-    /*
-    * PID calculation.
-    * @return The controller output as a float between outMin and outMax.
-    */
-    float compute(float pv, float sp);
-
+ 
+    /**
+     * PID calculation.
+     *
+     * @return The controller output as a float between outMin and outMax.
+     */
+    float compute(void);
+ 
     //Getters.
     float getInMin();
     float getInMax();
@@ -96,31 +163,31 @@
     float getPParam();
     float getIParam();
     float getDParam();
-
+ 
 private:
-    
+ 
     bool usingFeedForward;
     bool inAuto;
-    
+ 
     //Actual tuning parameters used in PID calculation.
     float Kc_;
     float tauR_;
     float tauD_;
-
+    
     //Raw tuning parameters.
     float pParam_;
     float iParam_;
     float dParam_;
-
+    
     //The point we want to reach.
-    float setPoint_;
+    float setPoint_;         
     //The thing we measure.
-    float processVariable_;
+    float processVariable_;  
     float prevProcessVariable_;
     //The output that affects the process variable.
-    float controllerOutput_;
+    float controllerOutput_; 
     float prevControllerOutput_;
-
+ 
     //We work in % for calculations so these will scale from
     //real world values to 0-100% and back again.
     float inMin_;
@@ -129,19 +196,31 @@
     float outMin_;
     float outMax_;
     float outSpan_;
-
+ 
     //The accumulated error, i.e. integral.
     float accError_;
     //The controller output bias.
     float bias_;
-
+ 
     //The interval between samples.
-    float tSample_;
-
+    float tSample_;          
+ 
     //Controller output as a real world value.
     volatile float realOutput_;
+ 
+};
+ 
+#endif /* PID_H */
+ 
+            
 
-};
 
-#endif 
+            
+
+
+    
 
+
+
+
+