【Arduino】168种传感器模块系列实验（158）---QMC5883L三轴罗盘

  【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
  项目之六：测试方向

  实验开源代码

/*
  【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
  实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
  项目之六：测试方向
  实验接线：
  QMC5883L-------------- UNO
  VCC------------------- 5V
  GND------------------- GND
  SCL ------------------- A5
  SDA------------------- A4
  DRDY------------------ N/C
*/

#include <QMC5883LCompass.h>

QMC5883LCompass compass;

void setup() {
  Serial.begin(9600);
  compass.init();
}

void loop() {
  compass.read();

  byte a = compass.getAzimuth();

  char myArray[3];
  compass.getDirection(myArray, a);

  Serial.print(myArray[0]);
  Serial.print(myArray[1]);
  Serial.print(myArray[2]);
  Serial.println();

  delay(250);
}
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实验串口返回情况

  【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
  实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
  项目之七：三轴XYZ实时数据

  实验开源代码

/*
  【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
  实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
  项目之七：三轴XYZ实时数据
  实验接线：
  5883L-------------- UNO
  VCC------------------- 5V
  GND------------------- GND
  SCL ------------------- A5
  SDA------------------- A4
  DRDY------------------ N/C
*/

#include <QMC5883LCompass.h>

QMC5883LCompass compass;

void setup() {
  Serial.begin(9600);
  Serial.print("5883L准备就绪");
  compass.init();

  /*
     调用 setSmoothing(STEPS, ADVANCED);

     STEPS = int 平滑结果的步数。有效 1 到 10。
     更高的步骤等于更平滑但更长的处理时间。

     ADVANCED = bool 打开或关闭高级平滑。True 将从每个步骤中删除最大值和最小值，然后正常处理。
     启用此功能将导致更加平滑，但需要更长的处理时间。

  */
  compass.setSmoothing(10, true);
}

void loop() {
  int x, y, z;

  // Read compass values
  compass.read();

  // Return XYZ readings
  x = compass.getX();
  y = compass.getY();
  z = compass.getZ();

  Serial.print("X: ");
  Serial.print(x);
  Serial.print(" Y: ");
  Serial.print(y);
  Serial.print(" Z: ");
  Serial.print(z);
  Serial.println();

  delay(250);
}
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实验串口返回情况

实验串口绘图器返回情况

   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目之八：简单的QMC5883L 指南针演示

  实验开源代码

/*
   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目之八：简单的QMC5883L 指南针演示
   实验接线：
   5883L-------------- UNO
   VCC------------------- 5V
   GND------------------- GND
   SCL ------------------- A5
   SDA------------------- A4
   DRDY------------------ N/C
*/

#include <QMC5883L.h>
#include <Wire.h>

QMC5883L compass;

void setup() {
  Wire.begin();

  compass.init();
  compass.setSamplingRate(50);

  Serial.begin(9600);
  Serial.println("QMC5883L 指南针演示");
  Serial.println("向各个方向转动罗盘来校准....");
}

void loop(){
  int heading = compass.readHeading();
  if (heading == 0) {
    /* Still calibrating, so measure but don't print */
  } else {
    Serial.println(heading);
  }
  delay(250);
}
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实验串口返回情况

   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目之九：动态四组数据，xyz+方位角a

  实验开源代码

/*
   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目之九：动态四组数据，xyz+方位角
   实验接线：
   5883L-------------- UNO
   VCC------------------- 5V
   GND------------------- GND
   SCL ------------------- A5
   SDA------------------- A4
   DRDY------------------ N/C
*/

#include <Wire.h>
#include <MechaQMC5883.h>

MechaQMC5883 qmc;

void setup() {
  Wire.begin();
  Serial.begin(9600);
  qmc.init();
  //qmc.setMode(Mode_Continuous,ODR_200Hz,RNG_2G,OSR_256);
}

void loop() {
  int x, y, z;
  int azimuth;
  //float azimuth; //is supporting float too
  qmc.read(&x, &y, &z, &azimuth);
  //azimuth = qmc.azimuth(&y,&x);//you can get custom azimuth
  Serial.print("x: ");
  Serial.print(x);
  Serial.print(" y: ");
  Serial.print(y);
  Serial.print(" z: ");
  Serial.print(z);
  Serial.print(" a: ");
  Serial.print(azimuth);
  Serial.println();
  delay(800);
}
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实验串口返回情况

实验串口绘图器返回情况

模块实验接线示意图

磁偏角(magnetic declination)
地磁偏角是指地球上任一处的磁北方向和正北方向之间的夹角。当地磁北向实际偏东时，地磁偏角为正，反之为负。地磁偏角在历史上最早由中国北宋科学家沈括记录在著作《梦溪笔谈》中：“方家以磁石磨针锋，则能指南，然常微偏东，不全南也。”而西方最早的记录则在此之后约400年。在地球上不同的地方，地磁偏角一般也不相同。在同一个地方，地磁偏角随着时间的推移也在不断变化。发生磁暴时和在磁力异常地区，如磁铁矿和高压线附近，地磁偏角将会产生急剧变化。在中国大陆的大部分地区，地磁偏角在-10°～+2°之间。在台湾则是-4°～-3°左右。正北(真北TN)：

方格北(图北GN)：以方格北线所测之方位角为方格方位角。
磁北(MN)：地磁偏角：当地磁北向实际偏东时，地磁偏角为正，反之为负。

指北针指的方向是磁北(MN)，假定磁偏角为偏东14度(14°E) ，正北(TN)会在磁北(MN)右边14度。xx°E：正北在磁北右边xx度。xx°W：正北在磁北左边xx度。

磁偏角是根据您当前位置应用的校正
为了从磁北得到真北，它因地而异。
例子：
基督城，东经 23° 35'
惠灵顿 , 22° 14' EAST
但尼丁，东经 25° 8'
奥克兰，东经 19° 30'

您所在地区的磁偏角可以从​​ http://www.magnetic-declination.com/ 获得

实际测量几个地方的磁偏角

   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目之十：根据当前位置来校正磁偏角

  实验开源代码

/*
   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目之十：根据当前位置来校正磁偏角
   实验接线：
   5883L-------------- UNO
   VCC------------------- 5V
   GND------------------- GND
   SCL ------------------- A5
   SDA------------------- A4
   DRDY------------------ N/C
*/

#include <Arduino.h>
#include <Wire.h>
#include <HMC5883L_Simple.h>

// Create a compass
HMC5883L_Simple Compass;

void setup() {
  Serial.begin(9600);
  Wire.begin();

  // Magnetic Declination is the correction applied according to your present location
  // in order to get True North from Magnetic North, it varies from place to place.
  //
  // The declination for your area can be obtained from http://www.magnetic-declination.com/
  // Take the "Magnetic Declination" line that it gives you in the information,
  //
  // Examples:
  //   Christchurch, 23° 35' EAST
  //   Wellington  , 22° 14' EAST
  //   Dunedin     , 25° 8'  EAST
  //   Auckland    , 19° 30' EAST
  //
  Compass.SetDeclination(-0, 23, 'W');

  //   The device can operate in SINGLE (default) or CONTINUOUS mode
  //   SINGLE simply means that it takes a reading when you request one
  //   CONTINUOUS means that it is always taking readings
  //   for most purposes, SINGLE is what you want.
  Compass.SetSamplingMode(COMPASS_CONTINUOUS);

  //   The scale can be adjusted to one of several levels, you can probably leave it at the default.
  //   Essentially this controls how sensitive the device is.
  //   Options are 088, 130 (default), 190, 250, 400, 470, 560, 810
  //   Specify the option as COMPASS_SCALE_xxx
  //   Lower values are more sensitive, higher values are less sensitive.
  //   The default is probably just fine, it works for me.  If it seems very noisy
  //  (jumping around), incrase the scale to a higher one.
  Compass.SetScale(COMPASS_SCALE_250);

  //   The compass has 3 axes, but two of them must be close to parallel to the earth's surface to read it,
  //   (we do not compensate for tilt, that's a complicated thing) - just like a real compass has a floating
  //   needle you can imagine the digital compass does too.
  //
  //   To allow you to mount the compass in different ways you can specify the orientation:
  //   COMPASS_HORIZONTAL_X_NORTH (default), the compass is oriented horizontally, top - side up. when pointing North the X silkscreen arrow will point North
  //   COMPASS_HORIZONTAL_Y_NORTH, top-side up, Y is the needle,when pointing North the Y silkscreen arrow will point North
  //   COMPASS_VERTICAL_X_EAST,    vertically mounted (tall) looking at the top side, when facing North the X silkscreen arrow will point East
  //   COMPASS_VERTICAL_Y_WEST,    vertically mounted (wide) looking at the top side, when facing North the Y silkscreen arrow will point West
  Compass.SetOrientation(COMPASS_HORIZONTAL_X_NORTH);
}

// Our main program loop.
void loop() {
  float heading = Compass.GetHeadingDegrees();

  Serial.print("Heading: \t");
  Serial.println( heading );
  delay(500);
}
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实验串口返回情况



项目之十实验说明：这是第二次无法完成磁偏角的校准
第一次是使用QMC5883L的库，这次是使用HMC5883L的库，而实验采用模块的芯片是国产的DB5883L
这是三种有一定差异的不同产家的芯片，估计是在校准程序上有些不能兼容，其他功能还没有发现不兼容的情况。

   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目十一：使用Adafruit库的HMC5883 磁力计测试

  实验开源代码

/*
   【Arduino】168种传感器模块系列实验（资料代码+图形编程+仿真编程）
   实验一百五十八：QMC5883L电子指南针罗盘模块 三轴磁场传感器GY-271
   项目十一：使用Adafruit库的HMC5883 磁力计测试
   实验接线：
   5883L-------------- UNO
   VCC------------------- 5V
   GND------------------- GND
   SCL ------------------- A5
   SDA------------------- A4
   DRDY------------------ N/C
*/

#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_HMC5883_U.h>

/* Assign a unique ID to this sensor at the same time */
Adafruit_HMC5883_Unified mag = Adafruit_HMC5883_Unified(666666);

void displaySensorDetails(void)
{
  sensor_t sensor;
  mag.getSensor(&sensor);
  Serial.println("------------------------------------");
  Serial.print  ("Sensor:       "); Serial.println(sensor.name);
  Serial.print  ("Driver Ver:   "); Serial.println(sensor.version);
  Serial.print  ("Unique ID:    "); Serial.println(sensor.sensor_id);
  Serial.print  ("Max Value:    "); Serial.print(sensor.max_value); Serial.println(" uT");
  Serial.print  ("Min Value:    "); Serial.print(sensor.min_value); Serial.println(" uT");
  Serial.print  ("Resolution:   "); Serial.print(sensor.resolution); Serial.println(" uT");
  Serial.println("------------------------------------");
  Serial.println("");
  delay(500);
}

void setup(void)
{
  Serial.begin(9600);
  Serial.println("HMC5883 Magnetometer Test"); Serial.println("");

  /* Initialise the sensor */
  if (!mag.begin())
  {
    /* There was a problem detecting the HMC5883 ... check your connections */
    Serial.println("Ooops, no HMC5883 detected ... Check your wiring!");
    while (1);
  }

  /* Display some basic information on this sensor */
  displaySensorDetails();
}

void loop(void)
{
  /* Get a new sensor event */
  sensors_event_t event;
  mag.getEvent(&event);

  /* Display the results (magnetic vector values are in micro-Tesla (uT)) */
  Serial.print("X: "); Serial.print(event.magnetic.x); Serial.print("  ");
  Serial.print("Y: "); Serial.print(event.magnetic.y); Serial.print("  ");
  Serial.print("Z: "); Serial.print(event.magnetic.z); Serial.print("  "); Serial.println("uT");

  // Hold the module so that Z is pointing 'up' and you can measure the heading with x&y
  // Calculate heading when the magnetometer is level, then correct for signs of axis.
  float heading = atan2(event.magnetic.y, event.magnetic.x);

  // 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: -13* 2' W, which is ~13 Degrees, or (which we need) 0.22 radians
  // If you cannot find your Declination, comment out these two lines, your compass will be slightly off.
  float declinationAngle = 0.1;
  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;

  Serial.print("Heading (degrees): "); Serial.println(headingDegrees);

  delay(500);
}
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实验串口返回情况