BalanceBot/IMU.ino

49 lines
1.4 KiB
C++

void readIMU() {
//Acceletometer
ax = convertInt(IMU.accelerometer_x(IMU.readFromAccelerometer()), acc_overflow_value);
ay = convertInt(IMU.accelerometer_y(IMU.readFromAccelerometer()), acc_overflow_value);
az = convertInt(IMU.accelerometer_z(IMU.readFromAccelerometer()), acc_overflow_value);
//Magnetometer
cx = IMU.compass_x(IMU.readFromCompass());
cy = IMU.compass_y(IMU.readFromCompass());
cz = IMU.compass_z(IMU.readFromCompass());
// Gyrocope
gx = convertInt(IMU.gyro_x(IMU.readGyro()), gyro_overflow_value); // gx - Pitch rate
gy = convertInt(IMU.gyro_y(IMU.readGyro()), gyro_overflow_value); // gy - Roll rate
gz = convertInt(IMU.gyro_z(IMU.readGyro()), gyro_overflow_value); // gz - Yaw rate
//Temperature sensor
gt = IMU.temp(IMU.readGyro());
// Pitch angle from accelerometer
acc_pitch = -1 * atan2(ax, sqrt((pow(ay, 2) + pow(az, 2)))) * 180.0 / PI;
//Pitch rate from gyroscope
pitch_rate = -gy;
//Complementary filter
pitch = acc_pitch * (1 - alpha) + (((pitch_rate * dT_s) + pitch_prev) * alpha);
pitch_prev = pitch;
}
int convertInt(int raw, int overflow_value_) {
//For some reason the ints in the example behaves as unsigned int.. Maybe look at the .cpp code, might be something there, if not. This works OK.
if (raw > (overflow_value_ / 2)) {
return (raw - overflow_value_);
}
else {
return raw;
}
}