Hallo Leute,
ich habe folgendes Problem.
Ich muss unbedingt brauchbare Werte der Himmelsrichtung in Grad bekommen ( 0 bis 360 )
Das wollte ich mit dem og. Kompassmodul realisieren.
Doch wenn ich den Example Sketch von der HMC5883L Lib lade ( siehe http://bildr.org/2012/02/hmc5883l_arduino/ )
dann bekomme ich im Terminal folgende Ausgabe wären des HMC Setups:
Starting the I2C interface.
Constructing new HMC5883L
Setting scale to +/- 1.3 Ga
Entered scale was not valid, valid gauss values are: 0.88, 1.3, 1.9, 2.5, 4.0, 4.7, 5.6, 8.1
Setting measurement mode to continous.
Entered scale was not valid, valid gauss values are: 0.88, 1.3, 1.9, 2.5, 4.0, 4.7, 5.6, 8.1
Raw: 134 99 -395 Scaled: 123.28 91.08 -363.40 Heading: 0.69 Radians 39.78 Degrees
Raw: 135 100 -395 Scaled: 124.20 92.00 -363.40 Heading: 0.70 Radians 39.85 Degrees
Raw: 135 99 -397 Scaled: 124.20 91.08 -365.24 Heading: 0.69 Radians 39.57 Degrees
Wieso war das scale not valid? Und wie hängt es mit meinen Ergebnissen zusammen?
Wenn ich das Kompassmodul flach auf den Tisch lege ( siehe Bild 1 und Bild 2 ) und das Breadboard drehe, bekomme ich nicht wirklich brauchbare Heading Angaben. Ich meine die können einfach nicht stimmen. Wo vorhin mal Kurs 90 war ist nun auf einmal Kurs zB 145. Sobald ich es nur etwas schräg halt habe ich sofort andere Kursdaten.
Könnt ihr mir helfen wieso ich diesen Fehler bekommen im HMC Setup?
Ich muss mich wirklich auf den Kurs verlassen können....
PS: Norden wäre eh dort wo die Y Achse hinzeigt oder?
danke schon mal im voraus.
lg
Dieter
PPS:
hier noch der Example Sketch:
// Reference the I2C Library
#include <Wire.h>
// Reference the HMC5883L Compass Library
#include <HMC5883L.h>
// Store our compass as a variable.
HMC5883L compass;
// 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()
{
// 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 = 0.05795;
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);
// 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(500);
}
// 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");
}
