OX
OX V1
Dependencies: mbed
Diff: zmu9250.h
- Revision:
- 0:6182212860fb
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/zmu9250.h Mon Dec 05 15:55:28 2016 +0000
@@ -0,0 +1,155 @@
+#include "mbed.h"
+#include "MPU9250.h"
+#include "math.h"
+
+
+
+class ZMU9250
+{
+ public:
+ ZMU9250()
+ {
+
+ //Set up I2C
+ i2c.frequency(400000); // use fast (400 kHz) I2C
+ this->t.start();
+
+ // Read the WHO_AM_I register, this is a good test of communication
+ uint8_t whoami = this->mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250
+ if (whoami == 0x73) // WHO_AM_I should always be 0x68
+ {
+ wait(1);
+ this->mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration
+ this->mpu9250.MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values
+ this->mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers
+ wait(2);
+ this->mpu9250.initMPU9250();
+ this->mpu9250.initAK8963(magCalibration);
+ wait(1);
+
+ }
+ else
+ {
+
+ while(1) ; // Loop forever if communication doesn't happen
+ }
+ this->mpu9250.getAres(); // Get accelerometer sensitivity
+ this->mpu9250.getGres(); // Get gyro sensitivity
+ this->mpu9250.getMres(); // Get magnetometer sensitivity
+ //magbias[0] = +470.; // User environmental x-axis correction in milliGauss, should be automatically calculated
+ //magbias[1] = +120.; // User environmental x-axis correction in milliGauss
+ //magbias[2] = +125.; // User environmental x-axis correction in milliGauss
+ magbias[0] = +470; // User environmental x-axis correction in milliGauss, should be automatically calculated
+ magbias[1] = +120; // User environmental x-axis correction in milliGauss
+ magbias[2] = +125; // User environmental x-axis correction in milliGauss
+ }
+
+ void Update()
+ {
+ if(this->mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt
+ this->mpu9250.readAccelData(accelCount); // Read the x/y/z adc values
+ // Now we'll calculate the accleration value into actual g's
+ ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
+ ay = (float)accelCount[1]*aRes - accelBias[1];
+ az = (float)accelCount[2]*aRes - accelBias[2];
+ this->mpu9250.readGyroData(gyroCount); // Read the x/y/z adc values
+ // Calculate the gyro value into actual degrees per second
+ gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
+ gy = (float)gyroCount[1]*gRes - gyroBias[1];
+ gz = (float)gyroCount[2]*gRes - gyroBias[2];
+ this->mpu9250.readMagData(magCount); // Read the x/y/z adc values
+ // Calculate the magnetometer values in milliGauss
+ // Include factory calibration per data sheet and user environmental corrections
+ mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]+360.0f; // get actual magnetometer value, this depends on scale being set
+ my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1]-210.0f;
+ mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2];
+ //aa.printf("x %f\ty %f\tz %f\n",mx,my,mz);
+
+
+ } // end if one
+ Now = this->t.read_us();
+ deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update
+ lastUpdate = Now;
+ this->sum += deltat;
+ sumCount++;
+ // Pass gyro rate as rad/s
+ if((rand()%20)>=0)
+ {
+ this->mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
+ }else
+ {
+ //this->mpu9250.MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
+ this->mpu9250.Mad_Update(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f);
+ }
+
+
+ // Serial print and/or display at 0.5 s rate independent of data rates
+ delt_t = this->t.read_ms() - count;
+ if (delt_t > 10) { // update LCD once per half-second independent of read rate
+ tempCount = this->mpu9250.readTempData(); // Read the adc values
+ temperature = ((float) tempCount) / 333.87f + 21.0f; // Temperature in degrees Centigrade
+ // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation.
+ // In this coordinate system, the positive z-axis is down toward Earth.
+ // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination, looking down on the sensor positive yaw is counterclockwise.
+ // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative.
+ // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll.
+ // These arise from the definition of the homogeneous rotation matrix constructed from quaternions.
+ // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be
+ // applied in the correct order which for this configuration is yaw, pitch, and then roll.
+ // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links.
+ yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]);
+ //yaw = atan2(2.0f * (q[0] * q[2] + q[0] * q[3]), 1 - 2 * ( q[2] * q[2] + q[3] * q[3]));
+ pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
+ roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]);
+ pitch *= 180.0f / PI;
+ yaw *= 180.0f / PI;
+ //yaw -= 13.8f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04
+ yaw -= 0.35f;
+ roll *= 180.0f / PI;
+ this->roll_x = roll;
+ this->pitch_y = pitch;
+ this->yaw_z = yaw;//(this->kal.getAngle(yaw*PI/180.0f,0.00,delt_t));
+ count = this->t.read_ms();
+ if(count > 1<<21) {
+ this->t.start(); // start the timer over again if ~30 minutes has passed
+ count = 0;
+ deltat= 0;
+ lastUpdate = this->t.read_us();
+ } // end if three.
+ this->sum = 0;
+ sumCount = 0;
+ } // end if two.
+ }
+
+
+ float Roll()
+ {
+ return roll_x;
+ }
+
+ float Pitch()
+ {
+ return pitch_y;
+ }
+
+ float Yaw()
+ {
+ return yaw_z;
+ }
+
+
+ private:
+ float sum;
+ uint32_t sumCount;
+ char buffer[14];
+ int roll_x;
+ kalman kal();
+ int pitch_y;
+ int yaw_z;
+ MPU9250 mpu9250;
+ Timer t;
+
+
+};
+
+