Samuel Lin
1
Fork of
PID
by 
Aaron Berk
Diff: PID.h
- Revision:
- 1:28542afc96d0
- Parent:
- 0:6e12a3e5af19
--- a/PID.h Thu Sep 02 16:48:10 2010 +0000
+++ b/PID.h Wed Feb 15 12:33:10 2017 +0000
@@ -44,170 +44,83 @@
* http://www.controlguru.com/
*/
-#ifndef PID_H
-#define PID_H
-
/**
* Includes
*/
#include "mbed.h"
-/**
- * Defines
- */
-#define MANUAL_MODE 0
-#define AUTO_MODE 1
-
-/**
- * Proportional-integral-derivative controller.
- */
-class PID {
-
-public:
+class PID
+{
- /**
- * 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);
+ public:
- /**
- * 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
- */
- void setTunings(float Kc, float tauI, float tauD);
+ //Constants used in some of the functions below
+ #define AUTOMATIC 1
+ #define MANUAL 0
+ #define DIRECT 0
+ #define REVERSE 1
- /**
- * Reinitializes controller internals. Automatically
- * called on a manual to auto transition.
- */
- void reset(void);
-
- /**
- * Set PID to manual or auto mode.
- *
- * @param mode 0 -> Manual
- * Non-zero -> Auto
- */
- void setMode(int mode);
-
- /**
- * 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);
+ //commonly used functions **************************************************************************
+ PID(double*, double*, double*, // * constructor. links the PID to the Input, Output, and
+ double, double, double, int, float*, float*); // Setpoint. Initial tuning parameters are also set here
+
+ void SetMode(int Mode); // * sets PID to either Manual (0) or Auto (non-0)
- /**
- * PID calculation.
- *
- * @return The controller output as a float between outMin and outMax.
- */
- float compute(void);
+ double Compute(float*); // * performs the PID calculation. it should be
+ // called every time loop() cycles. ON/OFF and
+ // calculation frequency can be set using SetMode
+ // SetSampleTime respectively
- //Getters.
- float getInMin();
- float getInMax();
- float getOutMin();
- float getOutMax();
- float getInterval();
- float getPParam();
- float getIParam();
- float getDParam();
+ void SetOutputLimits(double, double); //clamps the output to a specific range. 0-255 by default, but
+ //it's likely the user will want to change this depending on
+ //the application
+
-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_;
- //The thing we measure.
- float processVariable_;
- float prevProcessVariable_;
- //The output that affects the process variable.
- float controllerOutput_;
- float prevControllerOutput_;
+ //available but not commonly used functions ********************************************************
+ void SetTunings(double, double, // * While most users will set the tunings once in the
+ double); // constructor, this function gives the user the option
+ // of changing tunings during runtime for Adaptive control
+ void SetControllerDirection(int); // * Sets the Direction, or "Action" of the controller. DIRECT
+ // means the output will increase when error is positive. REVERSE
+ // means the opposite. it's very unlikely that this will be needed
+ // once it is set in the constructor.
+ void SetSampleTime(int); // * sets the frequency, in Milliseconds, with which
+ // the PID calculation is performed. default is 100
+
+
+
+ //Display functions ****************************************************************
+ double GetKp(); // These functions query the pid for interal values.
+ double GetKi(); // they were created mainly for the pid front-end,
+ double GetKd(); // where it's important to know what is actually
+ int GetMode(); // inside the PID.
+ int GetDirection(); //
- //We work in % for calculations so these will scale from
- //real world values to 0-100% and back again.
- float inMin_;
- float inMax_;
- float inSpan_;
- float outMin_;
- float outMax_;
- float outSpan_;
+ private:
+ void Initialize();
+
+ double dispKp; // * we'll hold on to the tuning parameters in user-entered
+ double dispKi; // format for display purposes
+ double dispKd; //
+
+ double kp; // * (P)roportional Tuning Parameter
+ double ki; // * (I)ntegral Tuning Parameter
+ double kd; // * (D)erivative Tuning Parameter
+
+ int controllerDirection;
- //The accumulated error, i.e. integral.
- float accError_;
- //The controller output bias.
- float bias_;
+ double *myInput; // * Pointers to the Input, Output, and Setpoint variables
+ double *myOutput; // This creates a hard link between the variables and the
+ double *mySetpoint; // PID, freeing the user from having to constantly tell us
+ // what these values are. with pointers we'll just know.
+
+ float lastTime;
+ double ITerm, lastInput;
- //The interval between samples.
- float tSample_;
-
- //Controller output as a real world value.
- volatile float realOutput_;
-
-};
-
-#endif /* PID_H */
+ float SampleTime;
+ double outMin, outMax;
+ bool inAuto;
+};
\ No newline at end of file