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MMK

IMU & ARDUINO UNO

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I have an Arduino UNO R3...... I actually wants to interface it with a 6DOF IMU so that I can get visual data on my computer from it........ I am a novice on programming the Microcontroller so plzz provide me source codes and useful links for the same! Also recommend me a good IMU too!


>>A code I found on the internet:-

 

#define Gyro_Sens 0.00333 // Gyro sensitivity = 3.33mV/deg/s
#define VPQ 0.00322581 // Volts Per Quid --- value of 3.3V/1023
#define ADC_Avg_Num 100.// Number of averaging readings for calibration
#define Rad2Deg 57.2957795 // 1 radian = 57.2957795 degrees
#define Deg2Rad 0.0174532925 // 0.0174532925 rads = 1 deg

//The minimum and maximum values that came from
//the accelerometer...
//You very well may need to change these
int minValx = 403;
int maxValx = 610;

int minValy = 401;
int maxValy = 614;

int minValz = 413;
int maxValz = 619;

//Calibration variables
float Gx_Cal, Gy_Cal, Gz_Cal;

float GyroRateX=0, GyroRateY=0, GyroAngleZ=0, GyroAngleZ_dt=0;
float AccAngleX=0, AccAngleY=0, AccAngleZ=0;

float Pitch, Yaw, Roll;

int AN[6]; // Hold analogRead data

unsigned long pre_time, print_clock=0;
float dtime;


void setup()
{
analogReference(EXTERNAL); // sets reference voltage to use voltage applied to VREF pin
Serial.begin(115200);
delay(300); // Give things time to "warm-up"

Calibrate(); // Calibrate sensors
pre_time = millis(); //store current time to be used as "previous" time
}



void loop()
{

if(millis()-pre_time>=20) // Read ADC and does Calculations every 20ms
{
dtime=millis()-pre_time; //current time - previous time
pre_time = millis(); //store current time to be used as "previous" time
dtime=dtime/1000.;

Read_ADC();
Calculate();
}


if(millis()-print_clock>=50) //print every 50ms
{
Serial.print(Pitch);
Serial.print(",");
Serial.print(Roll);
Serial.print(",");
Serial.println(Yaw);

print_clock=millis(); // store current time

} //end if


}





///////////////////////////////////////////////////////////////////////
//////////////////////// Functions ///////////////////////////////
///////////////////////////////////////////////////////////////////////



void Read_ADC(void)
{

AN[0] = analogRead(1); // Gyro_X
AN[1] = analogRead(0); // Gyro_Y
AN[2] = analogRead(2); // Gyro_Z
AN[3] = analogRead(5); // Acc_X
AN[4] = analogRead(4); // Acc_Y
AN[5] = analogRead(3); // Acc_Z
}



void Calculate(void)
{

// Gyro portion
//----------------------------------------------------------------
GyroRateX = -1.0*dtime * (((AN[0]*3.3)/1023.-Gx_Cal)/Gyro_Sens);
GyroRateY = dtime * (((AN[1]*3.3)/1023.-Gy_Cal)/Gyro_Sens);

GyroAngleZ_dt = dtime * (((AN[2]*3.3)/1023.-Gz_Cal)/Gyro_Sens);
GyroAngleZ += -1.0 * GyroAngleZ_dt * (1/(cos(Deg2Rad*Roll))); // convert Roll angle to Rads, find sin to use as scaler for Yaw

if(GyroAngleZ<0) GyroAngleZ+=360; // Keep within range of 0-360 deg
if(GyroAngleZ>=360) GyroAngleZ-=360;
//----------------------------------------------------------------

//convert read values to degrees -90 to 90 - Needed for atan2
int xAng = map(AN[3], minValx, maxValx, -90, 90);
int yAng = map(AN[4], minValy, maxValy, -90, 90);
int zAng = map(AN[5], minValz, maxValz, -90, 90);

//Caculate 360deg values like so: atan2(-yAng, -zAng)
//atan2 outputs the value of -π to π (radians)
//We are then converting the radians to degrees
AccAngleX = Rad2Deg * (atan2(-xAng, -zAng) + PI);
AccAngleY = Rad2Deg * (atan2(-yAng, -zAng) + PI);

// Keep angles between +-180deg
if(AccAngleX>180) AccAngleX=AccAngleX-360;

if(AccAngleY<=180) AccAngleY=-1.0*AccAngleY;
if(AccAngleY>180) AccAngleY=360-AccAngleY;

// Final values...
Roll = (0.98)*(Roll + GyroRateX) + (0.02)*(AccAngleX);
Pitch = (0.98)*(Pitch + GyroRateY) + (0.02)*(AccAngleY);
Yaw = GyroAngleZ;
}


// Reads and averages ADC values for calibration
float Avg_ADC(int ADC_In)
{
long ADC_Temp=0;
for(int i=0; i<ADC_Avg_Num; i++)
{
ADC_Temp = ADC_Temp+analogRead(ADC_In);
delay(10); // Delay 10ms due to gyro bandwidth limit of 140Hz (~7.1ms)
}
return VPQ*(ADC_Temp/ADC_Avg_Num); //Average ADC, convert to volts
}

void Calibrate(void)
{
Gx_Cal = Avg_ADC(1); // Gyro_x on pin 1
Gy_Cal = Avg_ADC(0); // Gyro_y on pin 0
Gz_Cal = Avg_ADC(2); // Gyro_z on pin 2
}

////////////////////////
//////// END CODE //////
////////////////////////

I found this code from a website....... Will it work if I use it in the below configuration?????
6DOF_arduino_hookup.png
And for visualization I use this Altitude Indicator below:-
Plz tell me if all of this stuff will work out......... and if not plz help me in making changes here....... PLZ HELP!!!
Edited by MMK

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