Hi to every one in the arduino forum.
I struggled with one problem for so many days.
I am using GY-88 , Arduino UNO.
my problem is calculating the compass value using the 3 Axis.
I am able to calculate the compass by TWO axis is very success full, by using atan2 function.
float heading = atan2(scaled.YAxis, scaled.XAxis);
but how to calculate the compass values by 3 axis values.
my complete code and library is here,
/*
// SDA PIN A4 // blue
// SCL PIN A5 // Green
// +3.3V // red
// GND // black
// Reference the I2C Library
#include <Wire.h>
// Reference the HMC5883L Compass Library
#include <HMC5883L.h>
#include "MPU6050.h"
// Store our compass as a variable.
HMC5883L compass;
MPU6050 accelgyro;
// Record any errors that may occur in the compass.
int error = 0;
// Out setup routine, here we will configure the microcontroller and compass.
void setup()
{
Wire.begin();
accelgyro.setI2CMasterModeEnabled(false);
accelgyro.setI2CBypassEnabled(true) ;
accelgyro.setSleepEnabled(false);
// Initialize the serial port.
Serial.begin(9600);
Serial.println("Starting the I2C interface.");
Wire.begin(); // Start the I2C interface.
Serial.println("Constructing new HMC5883L");
compass = HMC5883L(); // Construct a new HMC5883 compass.
Serial.println("Setting scale to +/- 1.3 Ga");
error = compass.SetScale(1.3); // Set the scale of the compass.
if(error != 0) // If there is an error, print it out.
Serial.println(compass.GetErrorText(error));
Serial.println("Setting measurement mode to continous.");
error = compass.SetMeasurementMode(Measurement_Continuous); // Set the measurement mode to Continuous
if(error != 0) // If there is an error, print it out.
Serial.println(compass.GetErrorText(error));
}
// Our main program loop.
void loop()
{
// Retrive the raw values from the compass (not scaled).
MagnetometerRaw raw = compass.ReadRawAxis();
// Retrived the scaled values from the compass (scaled to the configured scale).
MagnetometerScaled scaled = compass.ReadScaledAxis();
// Values are accessed like so:
int MilliGauss_OnThe_XAxis = scaled.XAxis;// (or YAxis, or ZAxis)
// Calculate heading when the magnetometer is level, then correct for signs of axis.
float heading = atan2(scaled.YAxis, scaled.XAxis);
/* // Once you have your heading, you must then add your 'Declination Angle', which is the 'Error' of the magnetic field in your location.
// Find yours here: http://www.magnetic-declination.com/
// Mine is: 2� 37' W, which is 2.617 Degrees, or (which we need) 0.0456752665 radians, I will use 0.0457
// If you cannot find your Declination, comment out these two lines, your compass will be slightly off.
float declinationAngle = 0.0457;
heading += declinationAngle;*/
// Set declination angle on your location and fix heading
// You can find your declination on: http://magnetic-declination.com/
// (+) Positive or (-) for negative
// For Bytom / Poland declination angle is 4'26E (positive)
// Formula: (deg + (min / 60.0)) / (180 / M_PI);
float declinationAngle = (4.0 + (26.0 / 60.0)) / (180 / M_PI);
heading += declinationAngle;
// Correct for when signs are reversed.
if(heading < 0)
heading += 2*PI;
// Check for wrap due to addition of declination.
if(heading > 2*PI)
heading -= 2*PI;
// Convert radians to degrees for readability.
float headingDegrees = heading * 180/M_PI;
// Output the data via the serial port.
Output(raw, scaled, heading, headingDegrees);
Serial.println(" ");
// Normally we would delay the application by 66ms to allow the loop
// to run at 15Hz (default bandwidth for the HMC5883L).
// However since we have a long serial out (104ms at 9600) we will let
// it run at its natural speed.
// delay(66);
delay(2000);
}
// Output the data down the serial port.
void Output(MagnetometerRaw raw, MagnetometerScaled scaled, float heading, float headingDegrees)
{
/* Serial.print("Raw:\t");
Serial.print(raw.XAxis);
Serial.print(" ");
Serial.print(raw.YAxis);
Serial.print(" ");
Serial.print(raw.ZAxis);
Serial.print(" \tScaled:\t");
Serial.print(scaled.XAxis);
Serial.print(" ");
Serial.print(scaled.YAxis);
Serial.print(" ");
Serial.print(scaled.ZAxis);*/
Serial.print(" \tHeading:\t");
//Serial.print(heading);
//Serial.print(" Radians \t");
Serial.print(headingDegrees);
Serial.println(" Degrees \t");
}
please help me.
Thanks in advance.
GYSenso.zip (126 KB)