Diff: main.cpp

Revision:

0:0af5376a3506

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Oct 06 07:21:33 2017 +0000
@@ -0,0 +1,71 @@
+#include "mbed.h"
+#include "math.h"
+
+DigitalIn button1(D8);
+AnalogIn potMeterIn(A1);
+
+float motor1DirectionPin;
+float motor1MagnitudePin;
+float referenceVelocity;  // in rad/s
+
+float GetReferenceVelocity()
+{
+    // Returns reference velocity in rad/s. 
+    // Positive value means clockwise rotation.
+    const float maxVelocity=8.4; // in rad/s of course!    
+    
+    if (button1)   
+        {
+        // Clockwise rotation      
+        referenceVelocity = potMeterIn * maxVelocity;
+        } 
+        else 
+        {
+        // Counterclockwise rotation       
+        referenceVelocity = -1*potMeterIn * maxVelocity;  
+        }
+    return referenceVelocity;
+}
+
+
+void SetMotor1(float motorValue)
+{
+    // Given -1<=motorValue<=1, this sets the PWM and direction
+    // bits for motor 1. Positive value makes motor rotating
+    // clockwise. motorValues outside range are truncated to
+    // within range
+    if (motorValue >=0) motor1DirectionPin=1;
+        else motor1DirectionPin=0;
+    if (fabs(motorValue)>1) motor1MagnitudePin = 1;
+        else motor1MagnitudePin = fabs(motorValue);
+
+}
+float FeedForwardControl(float referenceVelocity)
+{
+    // very simple linear feed-forward control
+    const float MotorGain=8.4; // unit: (rad/s) / PWM
+    float motorValue = referenceVelocity / MotorGain;
+    return motorValue;
+}
+        
+void MeasureAndControl(void)
+{
+    // This function measures the potmeter position, extracts a
+    // reference velocity from it, and controls the motor with 
+    // a simple FeedForward controller. Call this from a Ticker.
+    float referenceVelocity = GetReferenceVelocity();
+    float motorValue = FeedForwardControl(referenceVelocity);
+    SetMotor1(motorValue);
+}
+
+int main()
+{
+    while (true) 
+    {
+    GetReferenceVelocity();
+    FeedForwardControl(referenceVelocity);
+    MeasureAndControl();
+    printf("%f", referenceVelocity);
+    
+    }
+}
\ No newline at end of file