Revision 0:7f9b4ca968ae, committed 2016-02-18

Comitter:

weisnail

Date:

Thu Feb 18 04:25:52 2016 +0000

Child:

1:4df4895863cd

Commit message:

add PID library

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PID.cpp	Thu Feb 18 04:25:52 2016 +0000
@@ -0,0 +1,69 @@
+#include "PID.h"
+
+PID::PID(float setKp, float setKi, float setKd,  float setSampletime){
+    
+    Kp = 0.0;
+    Ki = 0.0;
+    Kd = 0.0;
+    error[0] = 0.0;
+    error[1] = 0.0;
+    error[2] = 0.0;
+    output = 0.0;
+    reference = 0.0;
+    sampletime = 0.0;
+    Outputlimit_bool = false;
+    Inputlimit_bool = false;
+    outputLimits_H = 0.0;
+    outputLimits_L = 0.0;
+    inputLimits_H = 0.0;
+    inputLimits_L = 0.0; 
+    feedbackvalue = 0.0;   
+    
+    Kp = setKp;
+    Ki = setKi/setSampletime;
+    Kd = setKd*setSampletime;
+    sampletime = setSampletime;   
+}
+
+void PID::SetOutputLimits(float setoutputLimits_H, float setoutputLimits_L){
+    Outputlimit_bool = true;
+    outputLimits_H = setoutputLimits_H;
+    outputLimits_L = setoutputLimits_L;    
+}
+
+void PID::SetInputLimits(float setinputLimits_H, float setinputLimits_L){
+    Inputlimit_bool = true;
+    inputLimits_H = setinputLimits_H;
+    inputLimits_L = setinputLimits_L;     
+}
+
+void PID::Compute(float setreference, float setfeedbackvalue){
+
+    if(Inputlimit_bool == true){
+        if( setreference >= inputLimits_H){
+            reference = inputLimits_H;
+        }else if( setreference <= inputLimits_L){
+            reference = inputLimits_L;
+        }
+    }else{
+        reference = setreference;
+    }
+    
+    feedbackvalue = setfeedbackvalue;
+    
+    error[0] = reference - feedbackvalue;
+    output = output + ( Kp + Ki + Kd )*error[0] + ( -Kp - 2.0*Kd )*error[1] + Kd*error[2];
+    error[2] = error[1];
+    error[1] = error[0];    
+    
+    if(Outputlimit_bool == true){
+        if( output >= outputLimits_H){
+            output = outputLimits_H;
+        }else if( output <= outputLimits_L){
+            output = outputLimits_L;
+        }
+    }else{
+        output = output;
+    }
+            
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PID.h	Thu Feb 18 04:25:52 2016 +0000
@@ -0,0 +1,44 @@
+#ifndef PID_H
+#define PID_H
+
+#include "mbed.h"
+
+class PID{
+    public:
+
+        PID(float setKp, float setKi, float setKd, float setSampletime);       
+        void SetOutputLimits(float setoutputLimits_H, float setoutputLimits_L);
+        void SetInputLimits(float setinputLimits_H, float setinputLimits_L);
+        void Compute(float setreference, float setfeedbackvalue);  
+        
+        float Kp;
+        float Ki;
+        float Kd;
+ 
+        float error[3];
+        float output;
+        float reference;
+
+        
+
+        
+        float sampletime;
+        
+        
+
+    private:
+    
+        bool Outputlimit_bool;
+        bool Inputlimit_bool;
+        
+        float outputLimits_H;
+        float outputLimits_L;
+        float inputLimits_H;
+        float inputLimits_L;
+        
+        float feedbackvalue;
+ //       Ticker PID_timer;
+
+};
+
+#endif /* PID_H*/
\ No newline at end of file