Category Archives: Arduino

In this video lesson we create a PyQt5 Widget in Python to help calibrate the QMC5883L 3-Axis Magnetometer on the GY-87 module. The Widget plots the data coming from the Magnetometer in real time to allow more accurate calibration.

This is the circuit schematic for our project:

MPU6050 — Schematic for connecting the GY-87 module to the Arduino

This is the simple code for the arduino to generate the raw data;

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
#include <QMC5883LCompass.h>
int x,y,z;
Adafruit_MPU6050 mpu;
QMC5883LCompass compass;
void setup() {
Serial.begin(115200);
mpu.begin();
mpu.setI2CBypass(true);
compass.init();
}
void loop() {
 compass.read();
 x = compass.getX();
 y = compass.getY();
 z = compass.getZ();
Serial.print(x);
Serial.print(',');
Serial.print(y);
Serial.print(',');
Serial.println(z);
 delay(100);
}

#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

#include <QMC5883LCompass.h>

int x,y,z;

Adafruit_MPU6050 mpu;

QMC5883LCompass compass;

void setup() {

Serial.begin(115200);

mpu.begin();

mpu.setI2CBypass(true);

compass.init();

}

void loop() {

compass.read();

x = compass.getX();

y = compass.getY();

z = compass.getZ();

Serial.print(x);

Serial.print(',');

Serial.print(y);

Serial.print(',');

Serial.println(z);

delay(100);

}

This is the code we run on the Python side to plot the raw data:

import serial
import numpy as np
from PyQt5 import QtWidgets, QtCore
import pyqtgraph as pg
serialPort = 'COM8'
baudRate =115200
to =.1
ser =serial.Serial(serialPort, baudRate, timeout=to)
maxPoints = 2000
xRaw = np.empty(0)
yRaw = np.empty(0)
zRaw = np.empty(0)

app = QtWidgets.QApplication([])
mainWindow = QtWidgets.QWidget()
mainWindow.setWindowTitle("Magnetometer Calibratioin")
mainLayout =QtWidgets.QVBoxLayout()
mainWindow.setLayout(mainLayout)
plotLayout =QtWidgets.QGridLayout()
mainLayout.addLayout(plotLayout)
xyPlot = pg.PlotWidget(title="XY Plane")
yzPlot = pg.PlotWidget(title="YZ Plane")
xzPlot = pg.PlotWidget(title="XZ Plane")
for plot in [xyPlot, yzPlot, xzPlot]:
    plot.setAspectLocked(True)
    plot.showGrid(x=True, y=True)
    plot.setMinimumSize(300,300)
plotLayout.addWidget(xyPlot, 0,0)
plotLayout.addWidget(yzPlot, 0,1)
plotLayout.addWidget(xzPlot, 1,0)

xyScatter = pg.ScatterPlotItem(size=5)
yzScatter = pg.ScatterPlotItem(size=5)
xzScatter = pg.ScatterPlotItem(size=5)

xyPlot.addItem(xyScatter)
yzPlot.addItem(yzScatter)
xzPlot.addItem(xzScatter)

def updatePlot():
    global xRaw, yRaw, zRaw
    if ser.in_waiting > 0:
        try:
            line= ser.readline().decode('utf-8').strip()
            print(line)
            values = line.split(',')
            if len(values)==3:
                x = float(values[0])
                y = float(values[1])
                z = float(values[2])
                xRaw =np.append(xRaw, x)[-maxPoints:]
                yRaw =np.append(yRaw, y)[-maxPoints:]
                zRaw =np.append(zRaw, z)[-maxPoints:]
                xyScatter.setData(x=xRaw, y=yRaw, brush=pg.mkBrush(0,0,255,120))
                yzScatter.setData(x=yRaw, y=zRaw, brush=pg.mkBrush(0,255,0,120))
                xzScatter.setData(x=xRaw, y=zRaw, brush=pg.mkBrush(255,0,0,120))
        
        except Exception as e:
            print("Parse Error: ", e)

plotTimer =QtCore.QTimer()
plotTimer.timeout.connect(updatePlot)
plotTimer.start(50)
mainWindow.show()
try:
    app.exec_()
finally:
    ser.close()

import serial

import numpy as np

from PyQt5 import QtWidgets, QtCore

import pyqtgraph as pg

serialPort = 'COM8'

baudRate =115200

to =.1

ser =serial.Serial(serialPort, baudRate, timeout=to)

maxPoints = 2000

xRaw = np.empty(0)

yRaw = np.empty(0)

zRaw = np.empty(0)

app = QtWidgets.QApplication([])

mainWindow = QtWidgets.QWidget()

mainWindow.setWindowTitle("Magnetometer Calibratioin")

mainLayout =QtWidgets.QVBoxLayout()

mainWindow.setLayout(mainLayout)

plotLayout =QtWidgets.QGridLayout()

mainLayout.addLayout(plotLayout)

xyPlot = pg.PlotWidget(title="XY Plane")

yzPlot = pg.PlotWidget(title="YZ Plane")

xzPlot = pg.PlotWidget(title="XZ Plane")

for plot in [xyPlot, yzPlot, xzPlot]:

plot.setAspectLocked(True)

plot.showGrid(x=True, y=True)

plot.setMinimumSize(300,300)

plotLayout.addWidget(xyPlot, 0,0)

plotLayout.addWidget(yzPlot, 0,1)

plotLayout.addWidget(xzPlot, 1,0)

xyScatter = pg.ScatterPlotItem(size=5)

yzScatter = pg.ScatterPlotItem(size=5)

xzScatter = pg.ScatterPlotItem(size=5)

xyPlot.addItem(xyScatter)

yzPlot.addItem(yzScatter)

xzPlot.addItem(xzScatter)

def updatePlot():

global xRaw, yRaw, zRaw

if ser.in_waiting > 0:

try:

line= ser.readline().decode('utf-8').strip()

print(line)

values = line.split(',')

if len(values)==3:

x = float(values[0])

y = float(values[1])

z = float(values[2])

xRaw =np.append(xRaw, x)[-maxPoints:]

yRaw =np.append(yRaw, y)[-maxPoints:]

zRaw =np.append(zRaw, z)[-maxPoints:]

xyScatter.setData(x=xRaw, y=yRaw, brush=pg.mkBrush(0,0,255,120))

yzScatter.setData(x=yRaw, y=zRaw, brush=pg.mkBrush(0,255,0,120))

xzScatter.setData(x=xRaw, y=zRaw, brush=pg.mkBrush(255,0,0,120))

except Exception as e:

print("Parse Error: ", e)

plotTimer =QtCore.QTimer()

plotTimer.timeout.connect(updatePlot)

plotTimer.start(50)

mainWindow.show()

try:

app.exec_()

finally:

ser.close()

Arduino

Calibrating a 3-Axis Magnetometer

September 20, 2025 admin

In this video lesson we show you how to calibrate the QMC5883L 3-axis magnetometer. The lesson is geared toward this specific magnetometer, but the procedure will be the same for any 3-axis magnetometer. We then use the calibrated reading to measure and calculate the magnetic heading of the device. With this, we have created a calibrated digital compass. In this lesson we are using the GY-87 module, which contains the QMC5883L magnetometer. We are connecting the module to the arduino using the following schematic:

In the video we develop two programs. The first program determines your sensor’s calibration constants. Then the second program uses those calibration constants to calculate heading, or yaw. The second program uses the offsets and scale parameters for MY PARTICULAR SENSOR. These values were determined using the first program. You must determine these values for your sensor, and then edit the second program to use your particular calibration parameters.

Program to determine your calibration parameters:

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
#include <QMC5883LCompass.h>
int x, y, z;
int xMax = -10000;
int xMin = 10000;
int yMax = -10000;
int yMin = 10000;
int zMax = -10000;
int zMin = 10000;
float xOffset, xScale, yOffset, yScale, zOffset, zScale;
Adafruit_MPU6050 mpu;
QMC5883LCompass compass;
void setup() {
  Serial.begin(115200);
  mpu.begin();
  mpu.setI2CBypass(true);
  compass.init();
}
void loop() {
  compass.read();
  x = compass.getX();
  y = compass.getY();
  z = compass.getZ();
  if (x > xMax) {
    xMax = x;
  }
  if (x < xMin) {
    xMin = x;
  }
  if (y>yMax){
    yMax=y;
  }
  if (y<yMin){
    yMin=y;
  }
  if (z > zMax) {
    zMax = z;
  }
  if (z < zMin) {
    zMin = z;
  }
  xOffset = (xMax + xMin) / 2.;
  yOffset = (yMax + yMin) / 2.;
  zOffset = (zMax + zMin) / 2.;
  xScale = 2. / (xMax - xMin);
  yScale = 2. / (yMax - yMin);
  zScale = 2. / (zMax - zMin);
  Serial.print(x);
  Serial.print(',');
  Serial.print(y);
  Serial.print(',');
  Serial.print(z);
    Serial.print(',');
  Serial.print(xMax);
  Serial.print(',');
  Serial.print(xMin);
  Serial.print(',');
  Serial.print(yMax);
  Serial.print(',');
  Serial.print(yMin);
  Serial.print(',');
  Serial.print(zMax);
  Serial.print(',');
  Serial.print(zMin);
  Serial.print(',');
  Serial.print(xOffset);
  Serial.print(',');
  Serial.print(yOffset);
  Serial.print(',');
  Serial.print(zOffset);
  Serial.print(',');
  Serial.print(xScale,5);
  Serial.print(',');
  Serial.print(yScale,5);
  Serial.print(',');
  Serial.println(zScale,5);
  delay(100);
}

#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

#include <QMC5883LCompass.h>

int x, y, z;

int xMax = -10000;

int xMin = 10000;

int yMax = -10000;

int yMin = 10000;

int zMax = -10000;

int zMin = 10000;

float xOffset, xScale, yOffset, yScale, zOffset, zScale;

Adafruit_MPU6050 mpu;

QMC5883LCompass compass;

void setup() {

Serial.begin(115200);

mpu.begin();

mpu.setI2CBypass(true);

compass.init();

}

void loop() {

compass.read();

x = compass.getX();

y = compass.getY();

z = compass.getZ();

if (x > xMax) {

xMax = x;

}

if (x < xMin) {

xMin = x;

}

if (y>yMax){

yMax=y;

}

if (y<yMin){

yMin=y;

}

if (z > zMax) {

zMax = z;

}

if (z < zMin) {

zMin = z;

}

xOffset = (xMax + xMin) / 2.;

yOffset = (yMax + yMin) / 2.;

zOffset = (zMax + zMin) / 2.;

xScale = 2. / (xMax - xMin);

yScale = 2. / (yMax - yMin);

zScale = 2. / (zMax - zMin);

Serial.print(x);

Serial.print(',');

Serial.print(y);

Serial.print(',');

Serial.print(z);

Serial.print(',');

Serial.print(xMax);

Serial.print(',');

Serial.print(xMin);

Serial.print(',');

Serial.print(yMax);

Serial.print(',');

Serial.print(yMin);

Serial.print(',');

Serial.print(zMax);

Serial.print(',');

Serial.print(zMin);

Serial.print(',');

Serial.print(xOffset);

Serial.print(',');

Serial.print(yOffset);

Serial.print(',');

Serial.print(zOffset);

Serial.print(',');

Serial.print(xScale,5);

Serial.print(',');

Serial.print(yScale,5);

Serial.print(',');

Serial.println(zScale,5);

delay(100);

}

Once you get your calibration parameters, then put them into this program. This program will then calculate your compass heading:

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
#include <QMC5883LCompass.h>
float x,y,z;
//The following numbers are for my particular sensor. You need
//to edit the following lines to put in your sensor calibration
//numbers
float xOffset=-382.5;
float yOffset=378.5;
float zOffset=1014.5;
float xScale = .00121;
float yScale=.00115;
float zScale=.00105;
float head;

Adafruit_MPU6050 mpu;
QMC5883LCompass compass;
void setup() {
Serial.begin(115200);
mpu.begin();
mpu.setI2CBypass(true);
compass.init();
}
void loop() {
 compass.read();
 x = (compass.getX()-xOffset)*xScale;
 y = (compass.getY()-yOffset)*yScale;
 z = (compass.getZ()-zOffset)*zScale;

// Serial.print(x);
// Serial.print(',');
// Serial.print(y);
// Serial.print(',');
// Serial.println(z);
head = atan2(y,x)*360/2/PI;
Serial.print("Heading: ");
Serial.println(head);
 delay(100);
}

#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

#include <QMC5883LCompass.h>

float x,y,z;

//The following numbers are for my particular sensor. You need

//to edit the following lines to put in your sensor calibration

//numbers

float xOffset=-382.5;

float yOffset=378.5;

float zOffset=1014.5;

float xScale = .00121;

float yScale=.00115;

float zScale=.00105;

float head;

Adafruit_MPU6050 mpu;

QMC5883LCompass compass;

void setup() {

Serial.begin(115200);

mpu.begin();

mpu.setI2CBypass(true);

compass.init();

}

void loop() {

compass.read();

x = (compass.getX()-xOffset)*xScale;

y = (compass.getY()-yOffset)*yScale;

z = (compass.getZ()-zOffset)*zScale;

// Serial.print(x);

// Serial.print(',');

// Serial.print(y);

// Serial.print(',');

// Serial.println(z);

head = atan2(y,x)*360/2/PI;

Serial.print("Heading: ");

Serial.println(head);

delay(100);

}

Arduino

Using the QMC5883L Magnetometers on the GY-87 Module

September 17, 2025 admin

In this video lesson we activate the QMC5883L 3-axis magnetometer on our GY-87 module. We show how to read the raw magnetic field strength in the x, y, and z axis. Your homework assignment will be to then calibrate the measurements such that you center the measured values around 0, and create a unit circle. This calibration will be very similar to what we did for the accelerometers a few weeks ago. This is the schematic we continue to use in this lesson:

This is the code we developed in todays lesson to read the raw data from the magnetometers.

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
#include <QMC5883LCompass.h>
int x,y,z;
Adafruit_MPU6050 mpu;
QMC5883LCompass compass;
void setup() {
Serial.begin(115200);
mpu.begin();
mpu.setI2CBypass(true);
compass.init();
}
void loop() {
 compass.read();
 x = compass.getX();
 y = compass.getY();
 z = compass.getZ();
Serial.print(x);
Serial.print(',');
Serial.print(y);
Serial.print(',');
Serial.println(z);
 delay(100);
}

#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

#include <QMC5883LCompass.h>

int x,y,z;

Adafruit_MPU6050 mpu;

QMC5883LCompass compass;

void setup() {

Serial.begin(115200);

mpu.begin();

mpu.setI2CBypass(true);

compass.init();

}

void loop() {

compass.read();

x = compass.getX();

y = compass.getY();

z = compass.getZ();

Serial.print(x);

Serial.print(',');

Serial.print(y);

Serial.print(',');

Serial.println(z);

delay(100);

}

Arduino

Improving MPU6050 IMU Arduino Project Performance with a Complimentary Filter

September 11, 2025 admin

In this video lesson I show you how you can improve the performance of your Arduino MPU6050 IMU Project by incorporating a complimentary filter. We will combine the roll and pitch calculations from the accelerometer and gyro into a fused result which allows us to enjoy the best of both worlds.

For your convenience, the code developed is presented below:

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
float Ax;
float Ay;
float Az;

float Gx;
float Gy;
float Gz;

float rollG=0;
float pitchG=0;
float yawG=0;

float gyroXOffset=0;
float gyroYOffset=0;
float gyroZOffset=0;

int tStart = millis();

// If You want Calibrated results, you must rotate
// your board to all possible orientations, and
// record your velues of xMax, xMin, yMax, yMin
// zMax, zMin. I show you how to do that in LESSON
// 79 on my youtube channel. Put in your values and then
// uncomment the code below. Don't use my values, you have
// to measure your own for it to work.

// float xMax= 1.03;
// float xMin= -.97;
// float yMax= .98;
// float yMin= -1.01;
// float zMax=.96 ;
// float zMin= -1.08;

// float xOffset = (xMax+xMin)/2;
// float yOffset = (yMax+yMin)/2;
// float zOffset = (zMax+zMin)/2;

// float xScale = 2/(xMax -xMin);
// float yScale = 2/(yMax - yMin);
// float zScale = 2/(zMax -zMin);

float rollLP = 0;
float pitchLP = 0;

float rollRAW;
float pitchRAW;

float rollComp=0;
float pitchComp=0;

float deltaRoll=0;
float deltaPitch=0;

Adafruit_MPU6050 mpu;

void calibrateGyro(){
Serial.println("Calibrating the Gyro: Keep Completely Stationary");
delay(1000);
int i;
float sumX = 0;
float sumY = 0;
float sumZ = 0;
int numPoints=100;
for (i=0;i<numPoints;i=i+1){
  sensors_event_t a, g, temp;
  mpu.getEvent(&a, &g, &temp);
  sumX = sumX + g.gyro.x;
  sumY = sumY + g.gyro.y;
  sumZ = sumZ + g.gyro.z;
  delay(10);
}
gyroXOffset = sumX/numPoints;
gyroYOffset = sumY/numPoints;
gyroZOffset = sumZ/numPoints;

}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  mpu.begin();
  Serial.println("MPU6050 Started!");
  mpu.setAccelerometerRange(MPU6050_RANGE_2_G);
  mpu.setGyroRange(MPU6050_RANGE_2000_DEG);
  mpu.setFilterBandwidth(MPU6050_BAND_21_HZ);
calibrateGyro();
tStart = millis();
}

void loop() {
  // put your main code here, to run repeatedly:
  sensors_event_t a, g, temp;
  mpu.getEvent(&a, &g, &temp);
  Ax = a.acceleration.x / 9.81;
  Ay = a.acceleration.y / 9.81;
  Az = a.acceleration.z / 9.81;

  Gx = g.gyro.x-gyroXOffset;
  Gy = -(g.gyro.y-gyroYOffset);
  Gz = g.gyro.z-gyroZOffset;

rollG = rollG + (millis() - tStart)/1000. * Gy *360./2./3.14;
pitchG = pitchG + (millis() - tStart)/1000. * Gx *360./2./3.14;
yawG = yawG + (millis() - tStart)/1000. * Gz *360./2./3.14;
deltaRoll=(millis() - tStart)/1000. * Gy *360./2./3.14;
deltaPitch=(millis() - tStart)/1000. * Gx *360./2./3.14;
tStart = millis();

  //Uncomment these lines of code to do the callibration
  //This will only work if you have measured your max
  //and min values, and put them in at the top of the code
  // Ax = xScale*(Ax-xOffset);
  // Ay = yScale*(Ay-yOffset);
  // Az = zScale*(Az-zOffset);

  pitchRAW = atan2(Ay, sqrt(Az * Az + Ax * Ax)) * 360 / (2 * 3.14);
  rollRAW = atan2(Ax, sqrt(Az * Az + Ay * Ay)) * 360 / (2 * 3.14);

  pitchLP = .75 * pitchLP + .25 * pitchRAW;
  rollLP = .75 * rollLP + .25 * rollRAW;

  rollComp= .1*rollRAW + .9*(rollComp + deltaRoll);
  pitchComp= .1*pitchRAW +.9*(pitchComp +deltaPitch);

  Serial.print("rollComp:");
  Serial.print(rollComp);
  Serial.print(',');
  Serial.print("pitchComp:");
  Serial.print(pitchComp);
  Serial.print(',');
  Serial.print("yawG:");
  Serial.print(yawG);
  Serial.print(',');
  // Serial.print("rollComp:");
  // Serial.print(rollComp);
  // Serial.print(',');
  // Serial.print("pitchG:");
  // Serial.print(pitchG);
  // Serial.print(',');
  // Serial.print("yawG:");
  // Serial.print(yawG);
  // Serial.print(',');
  Serial.print("UL:");
  Serial.print(90);
  Serial.print(',');
  Serial.print("LL:");
  Serial.println(-90);

  //   Serial.print("Ax:");
  //   Serial.print(Ax);
  //   Serial.print(',');
  //   Serial.print("Ay:");
  //   Serial.print(Ay);
  //   Serial.print(',');
  //     Serial.print("Az:");
  //   Serial.print(Az);
  //   Serial.print(',');
  //  Serial.print("UL:");
  //  Serial.print(1);
  //  Serial.print(',');
  //  Serial.print("LL:");
  //  Serial.println(-1);
  delay(1);
}

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#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

float Ax;

float Ay;

float Az;

float Gx;

float Gy;

float Gz;

float rollG=0;

float pitchG=0;

float yawG=0;

float gyroXOffset=0;

float gyroYOffset=0;

float gyroZOffset=0;

int tStart = millis();

// If You want Calibrated results, you must rotate

// your board to all possible orientations, and

// record your velues of xMax, xMin, yMax, yMin

// zMax, zMin. I show you how to do that in LESSON

// 79 on my youtube channel. Put in your values and then

// uncomment the code below. Don't use my values, you have

// to measure your own for it to work.

// float xMax= 1.03;

// float xMin= -.97;

// float yMax= .98;

// float yMin= -1.01;

// float zMax=.96 ;

// float zMin= -1.08;

// float xOffset = (xMax+xMin)/2;

// float yOffset = (yMax+yMin)/2;

// float zOffset = (zMax+zMin)/2;

// float xScale = 2/(xMax -xMin);

// float yScale = 2/(yMax - yMin);

// float zScale = 2/(zMax -zMin);

float rollLP = 0;

float pitchLP = 0;

float rollRAW;

float pitchRAW;

float rollComp=0;

float pitchComp=0;

float deltaRoll=0;

float deltaPitch=0;

Adafruit_MPU6050 mpu;

void calibrateGyro(){

Serial.println("Calibrating the Gyro: Keep Completely Stationary");

delay(1000);

int i;

float sumX = 0;

float sumY = 0;

float sumZ = 0;

int numPoints=100;

for (i=0;i<numPoints;i=i+1){

sensors_event_t a, g, temp;

mpu.getEvent(&a, &g, &temp);

sumX = sumX + g.gyro.x;

sumY = sumY + g.gyro.y;

sumZ = sumZ + g.gyro.z;

delay(10);

}

gyroXOffset = sumX/numPoints;

gyroYOffset = sumY/numPoints;

gyroZOffset = sumZ/numPoints;

}

void setup() {

// put your setup code here, to run once:

Serial.begin(115200);

mpu.begin();

Serial.println("MPU6050 Started!");

mpu.setAccelerometerRange(MPU6050_RANGE_2_G);

mpu.setGyroRange(MPU6050_RANGE_2000_DEG);

mpu.setFilterBandwidth(MPU6050_BAND_21_HZ);

calibrateGyro();

tStart = millis();

}

void loop() {

// put your main code here, to run repeatedly:

sensors_event_t a, g, temp;

mpu.getEvent(&a, &g, &temp);

Ax = a.acceleration.x / 9.81;

Ay = a.acceleration.y / 9.81;

Az = a.acceleration.z / 9.81;

Gx = g.gyro.x-gyroXOffset;

Gy = -(g.gyro.y-gyroYOffset);

Gz = g.gyro.z-gyroZOffset;

rollG = rollG + (millis() - tStart)/1000. * Gy *360./2./3.14;

pitchG = pitchG + (millis() - tStart)/1000. * Gx *360./2./3.14;

yawG = yawG + (millis() - tStart)/1000. * Gz *360./2./3.14;

deltaRoll=(millis() - tStart)/1000. * Gy *360./2./3.14;

deltaPitch=(millis() - tStart)/1000. * Gx *360./2./3.14;

tStart = millis();

//Uncomment these lines of code to do the callibration

//This will only work if you have measured your max

//and min values, and put them in at the top of the code

// Ax = xScale*(Ax-xOffset);

// Ay = yScale*(Ay-yOffset);

// Az = zScale*(Az-zOffset);

pitchRAW = atan2(Ay, sqrt(Az * Az + Ax * Ax)) * 360 / (2 * 3.14);

rollRAW = atan2(Ax, sqrt(Az * Az + Ay * Ay)) * 360 / (2 * 3.14);

pitchLP = .75 * pitchLP + .25 * pitchRAW;

rollLP = .75 * rollLP + .25 * rollRAW;

rollComp= .1*rollRAW + .9*(rollComp + deltaRoll);

pitchComp= .1*pitchRAW +.9*(pitchComp +deltaPitch);

Serial.print("rollComp:");

Serial.print(rollComp);

Serial.print(',');

Serial.print("pitchComp:");

Serial.print(pitchComp);

Serial.print(',');

Serial.print("yawG:");

Serial.print(yawG);

Serial.print(',');

// Serial.print("rollComp:");

// Serial.print(rollComp);

// Serial.print(',');

// Serial.print("pitchG:");

// Serial.print(pitchG);

// Serial.print(',');

// Serial.print("yawG:");

// Serial.print(yawG);

// Serial.print(',');

Serial.print("UL:");

Serial.print(90);

Serial.print(',');

Serial.print("LL:");

Serial.println(-90);

// Serial.print("Ax:");

// Serial.print(Ax);

// Serial.print(',');

// Serial.print("Ay:");

// Serial.print(Ay);

// Serial.print(',');

// Serial.print("Az:");

// Serial.print(Az);

// Serial.print(',');

// Serial.print("UL:");

// Serial.print(1);

// Serial.print(',');

// Serial.print("LL:");

// Serial.println(-1);

delay(1);

}

Arduino

Reducing Gyro Drift in MPU6050 IMU Arduino Project

September 11, 2025 admin

In this video lesson we learn how to reduce drift in our roll, pitch, and yaw from the MPU6050 IMU Arduino Project. We will be using the following schematic in today’s work.

This is the code we developed in this lesson:

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
float Ax;
float Ay;
float Az;

float Gx;
float Gy;
float Gz;

float rollG=0;
float pitchG=0;
float yawG=0;

float gyroXOffset=0;
float gyroYOffset=0;
float gyroZOffset=0;

int tStart = millis();

// If You want Calibrated results, you must rotate
// your board to all possible orientations, and
// record your velues of xMax, xMin, yMax, yMin
// zMax, zMin. I show you how to do that in LESSON
// 79 on my youtube channel. Put in your values and then
// uncomment the code below. Don't use my values, you have
// to measure your own for it to work.

// float xMax= 1.03;
// float xMin= -.97;
// float yMax= .98;
// float yMin= -1.01;
// float zMax=.96 ;
// float zMin= -1.08;

// float xOffset = (xMax+xMin)/2;
// float yOffset = (yMax+yMin)/2;
// float zOffset = (zMax+zMin)/2;

// float xScale = 2/(xMax -xMin);
// float yScale = 2/(yMax - yMin);
// float zScale = 2/(zMax -zMin);

float roll = 0;

float pitch = 0;
float rollRAW;
float pitchRAW;

Adafruit_MPU6050 mpu;

void calibrateGyro(){
Serial.println("Calibrating the Gyro: Keep Completely Stationary");
delay(1000);
int i;
float sumX = 0;
float sumY = 0;
float sumZ = 0;
int numPoints=1000;
for (i=0;i<numPoints;i=i+1){
  sensors_event_t a, g, temp;
  mpu.getEvent(&a, &g, &temp);
  sumX = sumX + g.gyro.x;
  sumY = sumY + g.gyro.y;
  sumZ = sumZ + g.gyro.z;
  delay(10);
}
gyroXOffset = sumX/numPoints;
gyroYOffset = sumY/numPoints;
gyroZOffset = sumZ/numPoints;

}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  mpu.begin();
  Serial.println("MPU6050 Started!");
  mpu.setAccelerometerRange(MPU6050_RANGE_2_G);
  mpu.setGyroRange(MPU6050_RANGE_2000_DEG);
  mpu.setFilterBandwidth(MPU6050_BAND_21_HZ);
calibrateGyro();
tStart = millis();
}

void loop() {
  // put your main code here, to run repeatedly:
  sensors_event_t a, g, temp;
  mpu.getEvent(&a, &g, &temp);
  Ax = a.acceleration.x / 9.81;
  Ay = a.acceleration.y / 9.81;
  Az = a.acceleration.z / 9.81;

  Gx = g.gyro.x-gyroXOffset;
  Gy = g.gyro.y-gyroYOffset;
  Gz = g.gyro.z-gyroZOffset;

rollG = rollG + (millis() - tStart)/1000. * Gy *360./2./3.14;
pitchG = pitchG + (millis() - tStart)/1000. * Gx *360./2./3.14;
yawG = yawG + (millis() - tStart)/1000. * Gz *360./2./3.14;
tStart = millis();

  //Uncomment these lines of code to do the callibration
  //This will only work if you have measured your max
  //and min values, and put them in at the top of the code
  // Ax = xScale*(Ax-xOffset);
  // Ay = yScale*(Ay-yOffset);
  // Az = zScale*(Az-zOffset);

  pitchRAW = atan2(Ay, sqrt(Az * Az + Ax * Ax)) * 360 / (2 * 3.14);
  rollRAW = atan2(Ax, sqrt(Az * Az + Ay * Ay)) * 360 / (2 * 3.14);

  pitch = .75 * pitch + .25 * pitchRAW;
  roll = .75 * roll + .25 * rollRAW;

  Serial.print("Gx:");
  Serial.print(Gx);
  Serial.print(',');
  Serial.print("Gy:");
  Serial.print(Gy);
  Serial.print(',');
  Serial.print("Gz:");
  Serial.print(Gz);
  Serial.print(',');
  Serial.print("rollG:");
  Serial.print(rollG);
  Serial.print(',');
  Serial.print("pitchG:");
  Serial.print(pitchG);
  Serial.print(',');
  Serial.print("yawG:");
  Serial.print(yawG);
  Serial.print(',');
  Serial.print("UL:");
  Serial.print(90);
  Serial.print(',');
  Serial.print("LL:");
  Serial.println(-90);

  //   Serial.print("Ax:");
  //   Serial.print(Ax);
  //   Serial.print(',');
  //   Serial.print("Ay:");
  //   Serial.print(Ay);
  //   Serial.print(',');
  //     Serial.print("Az:");
  //   Serial.print(Az);
  //   Serial.print(',');
  //  Serial.print("UL:");
  //  Serial.print(1);
  //  Serial.print(',');
  //  Serial.print("LL:");
  //  Serial.println(-1);
  delay(1);
}

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#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

float Ax;

float Ay;

float Az;

float Gx;

float Gy;

float Gz;

float rollG=0;

float pitchG=0;

float yawG=0;

float gyroXOffset=0;

float gyroYOffset=0;

float gyroZOffset=0;

int tStart = millis();

// If You want Calibrated results, you must rotate

// your board to all possible orientations, and

// record your velues of xMax, xMin, yMax, yMin

// zMax, zMin. I show you how to do that in LESSON

// 79 on my youtube channel. Put in your values and then

// uncomment the code below. Don't use my values, you have

// to measure your own for it to work.

// float xMax= 1.03;

// float xMin= -.97;

// float yMax= .98;

// float yMin= -1.01;

// float zMax=.96 ;

// float zMin= -1.08;

// float xOffset = (xMax+xMin)/2;

// float yOffset = (yMax+yMin)/2;

// float zOffset = (zMax+zMin)/2;

// float xScale = 2/(xMax -xMin);

// float yScale = 2/(yMax - yMin);

// float zScale = 2/(zMax -zMin);

float roll = 0;

float pitch = 0;

float rollRAW;

float pitchRAW;

Adafruit_MPU6050 mpu;

void calibrateGyro(){

Serial.println("Calibrating the Gyro: Keep Completely Stationary");

delay(1000);

int i;

float sumX = 0;

float sumY = 0;

float sumZ = 0;

int numPoints=1000;

for (i=0;i<numPoints;i=i+1){

sensors_event_t a, g, temp;

mpu.getEvent(&a, &g, &temp);

sumX = sumX + g.gyro.x;

sumY = sumY + g.gyro.y;

sumZ = sumZ + g.gyro.z;

delay(10);

}

gyroXOffset = sumX/numPoints;

gyroYOffset = sumY/numPoints;

gyroZOffset = sumZ/numPoints;

}

void setup() {

// put your setup code here, to run once:

Serial.begin(115200);

mpu.begin();

Serial.println("MPU6050 Started!");

mpu.setAccelerometerRange(MPU6050_RANGE_2_G);

mpu.setGyroRange(MPU6050_RANGE_2000_DEG);

mpu.setFilterBandwidth(MPU6050_BAND_21_HZ);

calibrateGyro();

tStart = millis();

}

void loop() {

// put your main code here, to run repeatedly:

sensors_event_t a, g, temp;

mpu.getEvent(&a, &g, &temp);

Ax = a.acceleration.x / 9.81;

Ay = a.acceleration.y / 9.81;

Az = a.acceleration.z / 9.81;

Gx = g.gyro.x-gyroXOffset;

Gy = g.gyro.y-gyroYOffset;

Gz = g.gyro.z-gyroZOffset;

rollG = rollG + (millis() - tStart)/1000. * Gy *360./2./3.14;

pitchG = pitchG + (millis() - tStart)/1000. * Gx *360./2./3.14;

yawG = yawG + (millis() - tStart)/1000. * Gz *360./2./3.14;

tStart = millis();

//Uncomment these lines of code to do the callibration

//This will only work if you have measured your max

//and min values, and put them in at the top of the code

// Ax = xScale*(Ax-xOffset);

// Ay = yScale*(Ay-yOffset);

// Az = zScale*(Az-zOffset);

pitchRAW = atan2(Ay, sqrt(Az * Az + Ax * Ax)) * 360 / (2 * 3.14);

rollRAW = atan2(Ax, sqrt(Az * Az + Ay * Ay)) * 360 / (2 * 3.14);

pitch = .75 * pitch + .25 * pitchRAW;

roll = .75 * roll + .25 * rollRAW;

Serial.print("Gx:");

Serial.print(Gx);

Serial.print(',');

Serial.print("Gy:");

Serial.print(Gy);

Serial.print(',');

Serial.print("Gz:");

Serial.print(Gz);

Serial.print(',');

Serial.print("rollG:");

Serial.print(rollG);

Serial.print(',');

Serial.print("pitchG:");

Serial.print(pitchG);

Serial.print(',');

Serial.print("yawG:");

Serial.print(yawG);

Serial.print(',');

Serial.print("UL:");

Serial.print(90);

Serial.print(',');

Serial.print("LL:");

Serial.println(-90);

// Serial.print("Ax:");

// Serial.print(Ax);

// Serial.print(',');

// Serial.print("Ay:");

// Serial.print(Ay);

// Serial.print(',');

// Serial.print("Az:");

// Serial.print(Az);

// Serial.print(',');

// Serial.print("UL:");

// Serial.print(1);

// Serial.print(',');

// Serial.print("LL:");

// Serial.println(-1);

delay(1);

}

Technology Tutorials

Category Archives: Arduino

Plotting X-Y-Z Magnetometer Data for Accurate Calibration

Calibrating a 3-Axis Magnetometer

Using the QMC5883L Magnetometers on the GY-87 Module

Improving MPU6050 IMU Arduino Project Performance with a Complimentary Filter

Reducing Gyro Drift in MPU6050 IMU Arduino Project

Making The World a Better Place One High Tech Project at a Time. Enjoy!