Arduino IMU Project with SSD1306 OLED and GY-87 Module with Compass and Roll Avionics Display

In this video lesson we add a Roll dial to our SSD1306 Avionics display on our Arduino IMU project. For this project, we are using the GY-87 IMU module. This is the schematic for the project:

OLED IMU — This schematic shows how to connect the SSD1306 OLED to our IMU Project.

For your convenience, this is the code we developed in the video. Remember, you have to edit the program to use the calibration parameters for your IMU module. I showed you how to get those parameters, and calibrate your sensors in THIS LESSON.

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
#include <QMC5883LCompass.h>

#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <math.h>

int screenWidth=128;
int screenHeight=64;
int rst = -1;
Adafruit_SSD1306 dsp(screenWidth, screenHeight, &Wire, rst);

float AxRaw,AyRaw,AzRaw,GxRaw,GyRaw,GzRaw,MxRaw,MyRaw,MzRaw;
float AxCal,AyCal,AzCal,GxCal,GyCal,GzCal,MxCal,MyCal,MzCal;
float rollA,pitchA,yawM,rollC,pitchC,yawC;
float rollG = 0;
float pitchG =0 ;
float yawG = 0;
float deltaRoll = 0;
float deltaPitch = 0;
float deltaYaw = 0;
float alpha = .1;

float rollCrad;
float pitchCrad;
float MxCalH;
float MyCalH;

int tStart =millis();
Adafruit_MPU6050 mpu;
QMC5883LCompass compass;

void setup() {
  // put your setup code here, to run once:
Serial.begin(115200);

dsp.begin(SSD1306_SWITCHCAPVCC,0x3C);
dsp.clearDisplay();
dsp.display();

mpu.begin();
mpu.setI2CBypass(true);
compass.init();
mpu.setGyroRange(MPU6050_RANGE_1000_DEG);
delay(100);
}

void calibrateSensors() {
    const float axOffset = 0.45407887789180545;
    const float ayOffset = 0.09432915233553185;
    const float azOffset = -0.4614157209191969;
    const float axScale = 0.10141341897341144;
    const float ayScale = 0.10141341897341144;
    const float azScale = 0.10141341897341144;
    const float gxOffset = -2.277507235645022;
    const float gyOffset = 0.8794902155258137;
    const float gzOffset = -0.5729577951308232;
    const float mxOffset = -103.48885017294003;
    const float myOffset = -96.80085481152321;
    const float mzOffset = 923.8042898128733;
    const float mxScale = 0.001156333898601669;
    const float myScale = 0.001012882116988885;
    const float mzScale = 0.0009400860982065997;


    AxCal = (AxRaw - axOffset) * axScale;
    AyCal = (AyRaw - ayOffset) * ayScale;
    AzCal = (AzRaw - azOffset) * azScale;
    GxCal = GxRaw*180/PI - gxOffset;
    GyCal = GyRaw*180/PI - gyOffset;
    GzCal = GzRaw*180/PI - gzOffset;
    MxCal = (MxRaw - mxOffset) * mxScale;
    MyCal = (MyRaw - myOffset) * myScale;
    MzCal = (MzRaw - mzOffset) * mzScale;
}
void updateDial(){
int radius=20;
int offset=3;
int x1Center = radius;
int y1Center = 63 - radius;
int x2Center = x1Center+2*radius+offset;
int y2Center = 63-radius;

int x1;
int y1;
int x2;
int y2;
float angleRad;
float tickScale;
dsp.drawCircle(x1Center,y1Center,radius, WHITE);
for (int i=0; i<=360; i=i+30){
  angleRad = i*PI/180;
  tickScale=.9;
  if (i%90==0){
    tickScale=.7;
  }
  x1 =x1Center + int(tickScale*radius*cos(angleRad));
  y1 =y1Center + int(tickScale*radius*sin(angleRad));
  x2 = x1Center + int(radius*cos(angleRad));
  y2 = y1Center + int(radius*sin(angleRad));
  dsp.drawLine(x1,y1,x2,y2,WHITE);
}
x1=x1Center;
y1=y1Center;
x2= x1Center + radius*cos(-(yawC+90)*PI/180);
y2= y1Center + radius*sin(-(yawC+90)*PI/180);
dsp.drawLine(x1,y1,x2,y2,WHITE);

dsp.drawCircle(x2Center,y2Center,radius,WHITE);
dsp.drawLine(x2Center-radius*cos(rollC*PI/180),y2Center-radius*sin(rollC*PI/180),x2Center+radius*cos(rollC*PI/180),y2Center+radius*sin(rollC*PI/180),WHITE);
}

void loop() {
  // put your main code here, to run repeatedly:
compass.read();
sensors_event_t a, g, temp;
mpu.getEvent(&a, &g, &temp);

AxRaw = a.acceleration.x;
AyRaw = a.acceleration.y;
AzRaw = a.acceleration.z;

GxRaw = g.gyro.x;
GyRaw = g.gyro.y;
GzRaw = g.gyro.z;

MxRaw= compass.getX();
MyRaw= compass.getY();
MzRaw= compass.getZ();

calibrateSensors();

rollA = atan2(AyCal,sqrt(AzCal*AzCal + AxCal*AxCal))*180/PI;
pitchA = atan2(AxCal,sqrt(AzCal*AzCal + AyCal*AyCal))*180/PI;

deltaRoll = GxCal*(millis()-tStart)/1000.;
deltaPitch = -GyCal*(millis()-tStart)/1000.;
deltaYaw = -GzCal*(millis()-tStart)/1000.;
tStart = millis();

rollG = rollG + deltaRoll;
pitchG = pitchG + deltaPitch;
yawG = yawG + deltaYaw;

rollC = alpha*(rollA) + (1-alpha)*(rollC+deltaRoll);
pitchC = alpha*(pitchA) + (1-alpha)*(pitchC+deltaPitch);

rollCrad=rollC*PI/180;
pitchCrad=pitchC*PI/180;

MxCalH=MxCal*cos(pitchCrad)-MyCal*sin(rollCrad)*sin(pitchCrad)-MzCal*cos(rollCrad)*sin(pitchCrad);
MyCalH=MyCal*cos(rollCrad) - MzCal*sin(rollCrad);

yawM = atan2(MyCalH,MxCalH)*180./PI;
yawM=int(yawM+360)%360;
if (abs(yawM-yawC)>=180){
  yawC=yawM;
}
if (abs(yawM-yawC)<180){
yawC = alpha*(yawM) + (1-alpha)*(yawC + deltaYaw);
}

// Serial.print("yawC:");Serial.print(yawC);Serial.print(',');
// Serial.print("yawM:");Serial.print(yawM);Serial.print(',');
// Serial.print("yawG:");Serial.print(yawG);Serial.print(',');
// Serial.print("LL:");Serial.print(-90);Serial.print(',');
// Serial.print("UL:");Serial.println(90);

Serial.print("rollC:");Serial.print(rollC);Serial.print(',');
Serial.print("pitchC:");Serial.print(pitchC);Serial.print(',');
Serial.print("yawC:");Serial.print(yawC);Serial.print(',');
Serial.print("LL:");Serial.print(-90);Serial.print(',');
Serial.print("UL:");Serial.println(90);

dsp.clearDisplay();
dsp.setTextColor(WHITE);
dsp.setCursor(0,0);
dsp.print("Ultimate Avionics");
dsp.setCursor(0,9);
dsp.print("R: "); dsp.print(int(rollC));
dsp.setCursor(40,9);
dsp.print("P: ");dsp.print(int(pitchC));
dsp.setCursor(80,9);
dsp.print("Y: ");dsp.print(int(yawC));

updateDial();

dsp.display();
delay(100);
}

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

#include <QMC5883LCompass.h>

#include <Adafruit_GFX.h>

#include <Adafruit_SSD1306.h>

#include <math.h>

int screenWidth=128;

int screenHeight=64;

int rst = -1;

Adafruit_SSD1306 dsp(screenWidth, screenHeight, &Wire, rst);

float AxRaw,AyRaw,AzRaw,GxRaw,GyRaw,GzRaw,MxRaw,MyRaw,MzRaw;

float AxCal,AyCal,AzCal,GxCal,GyCal,GzCal,MxCal,MyCal,MzCal;

float rollA,pitchA,yawM,rollC,pitchC,yawC;

float rollG = 0;

float pitchG =0 ;

float yawG = 0;

float deltaRoll = 0;

float deltaPitch = 0;

float deltaYaw = 0;

float alpha = .1;

float rollCrad;

float pitchCrad;

float MxCalH;

float MyCalH;

int tStart =millis();

Adafruit_MPU6050 mpu;

QMC5883LCompass compass;

void setup() {

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

Serial.begin(115200);

dsp.begin(SSD1306_SWITCHCAPVCC,0x3C);

dsp.clearDisplay();

dsp.display();

mpu.begin();

mpu.setI2CBypass(true);

compass.init();

mpu.setGyroRange(MPU6050_RANGE_1000_DEG);

delay(100);

}

void calibrateSensors() {

const float axOffset = 0.45407887789180545;

const float ayOffset = 0.09432915233553185;

const float azOffset = -0.4614157209191969;

const float axScale = 0.10141341897341144;

const float ayScale = 0.10141341897341144;

const float azScale = 0.10141341897341144;

const float gxOffset = -2.277507235645022;

const float gyOffset = 0.8794902155258137;

const float gzOffset = -0.5729577951308232;

const float mxOffset = -103.48885017294003;

const float myOffset = -96.80085481152321;

const float mzOffset = 923.8042898128733;

const float mxScale = 0.001156333898601669;

const float myScale = 0.001012882116988885;

const float mzScale = 0.0009400860982065997;

AxCal = (AxRaw - axOffset) * axScale;

AyCal = (AyRaw - ayOffset) * ayScale;

AzCal = (AzRaw - azOffset) * azScale;

GxCal = GxRaw*180/PI - gxOffset;

GyCal = GyRaw*180/PI - gyOffset;

GzCal = GzRaw*180/PI - gzOffset;

MxCal = (MxRaw - mxOffset) * mxScale;

MyCal = (MyRaw - myOffset) * myScale;

MzCal = (MzRaw - mzOffset) * mzScale;

}

void updateDial(){

int radius=20;

int offset=3;

int x1Center = radius;

int y1Center = 63 - radius;

int x2Center = x1Center+2*radius+offset;

int y2Center = 63-radius;

int x1;

int y1;

int x2;

int y2;

float angleRad;

float tickScale;

dsp.drawCircle(x1Center,y1Center,radius, WHITE);

for (int i=0; i<=360; i=i+30){

angleRad = i*PI/180;

tickScale=.9;

if (i%90==0){

tickScale=.7;

}

x1 =x1Center + int(tickScale*radius*cos(angleRad));

y1 =y1Center + int(tickScale*radius*sin(angleRad));

x2 = x1Center + int(radius*cos(angleRad));

y2 = y1Center + int(radius*sin(angleRad));

dsp.drawLine(x1,y1,x2,y2,WHITE);

}

x1=x1Center;

y1=y1Center;

x2= x1Center + radius*cos(-(yawC+90)*PI/180);

y2= y1Center + radius*sin(-(yawC+90)*PI/180);

dsp.drawLine(x1,y1,x2,y2,WHITE);

dsp.drawCircle(x2Center,y2Center,radius,WHITE);

dsp.drawLine(x2Center-radius*cos(rollC*PI/180),y2Center-radius*sin(rollC*PI/180),x2Center+radius*cos(rollC*PI/180),y2Center+radius*sin(rollC*PI/180),WHITE);

}

void loop() {

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

compass.read();

sensors_event_t a, g, temp;

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

AxRaw = a.acceleration.x;

AyRaw = a.acceleration.y;

AzRaw = a.acceleration.z;

GxRaw = g.gyro.x;

GyRaw = g.gyro.y;

GzRaw = g.gyro.z;

MxRaw= compass.getX();

MyRaw= compass.getY();

MzRaw= compass.getZ();

calibrateSensors();

rollA = atan2(AyCal,sqrt(AzCal*AzCal + AxCal*AxCal))*180/PI;

pitchA = atan2(AxCal,sqrt(AzCal*AzCal + AyCal*AyCal))*180/PI;

deltaRoll = GxCal*(millis()-tStart)/1000.;

deltaPitch = -GyCal*(millis()-tStart)/1000.;

deltaYaw = -GzCal*(millis()-tStart)/1000.;

tStart = millis();

rollG = rollG + deltaRoll;

pitchG = pitchG + deltaPitch;

yawG = yawG + deltaYaw;

rollC = alpha*(rollA) + (1-alpha)*(rollC+deltaRoll);

pitchC = alpha*(pitchA) + (1-alpha)*(pitchC+deltaPitch);

rollCrad=rollC*PI/180;

pitchCrad=pitchC*PI/180;

MxCalH=MxCal*cos(pitchCrad)-MyCal*sin(rollCrad)*sin(pitchCrad)-MzCal*cos(rollCrad)*sin(pitchCrad);

Technology Tutorials

Arduino IMU Project with SSD1306 OLED and GY-87 Module with Compass and Roll Avionics Display

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