fix speedometer buffer

lib/Speedometer/speedometer.h

@@ -22,14 +22,15 @@
  * @brief The default size of numbers to be taken in account for the average.
  * 
  */
-#define BUFSIZE 10
+#define BUFSIZE 5
+#define CONVERSION_FACTOR
 
 /**
  * @brief Default value for min Millisseconds between each loop
  * @see setDelay(uint8_t val)
  */
 #define DELAY_SPEEDOMETER 30
-#define PI 3.1415926535897932384626433832795
+#define PI 3.141592
 
 /**
  * @brief A class which use a encoder to calc the speed
@@ -126,7 +127,8 @@ class Speedometer {
          * 
          * @return double speed in m/s
          */
-        double getSpeed() { return this->speed; }
+        double getSpeed() const { return this->speed; }
+        double getAvgSpeed() const;
 
         /**
          * @brief Start calibration
@@ -153,7 +155,7 @@ class Speedometer {
         void clearAvgBuf();
         void addValToBuf(int16_t val);
         void updateAvgBufSize();
-        int16_t calcAverage();
+        int16_t calcAverage() const;
 
         Counter* pulseCounter;
         Direction currentDirection = Direction::None;