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Dependencies: HCSR04_2 MPU6050_2 mbed SDFileSystem3
Fork of Autoflight2018_12 by
MPU9250/MPU9250.cpp
- Committer:
- HARUKIDELTA
- Date:
- 2018-09-07
- Revision:
- 0:17f575135219
File content as of revision 0:17f575135219:
#include "mbed.h" #include "math.h" #include "MPU9250.h" MPU9250::MPU9250(PinName sda, PinName scl, RawSerial* serial_p) : i2c_p(new I2C(sda,scl)), i2c(*i2c_p), pc_p(serial_p) { initializeValue(); } MPU9250::~MPU9250(){} /*---------- public function ----------*/ bool MPU9250::Initialize(void){ uint8_t whoami; i2c.frequency(400000); // use fast (400 kHz) I2C timer.start(); whoami = Whoami_MPU9250(); pc_p->printf("I AM 0x%x\n\r", whoami); pc_p->printf("I SHOULD BE 0x71\n\r"); if(whoami == IAM_MPU9250){ resetMPU9250(); // Reset registers to default in preparation for device calibration calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers wait(1); initMPU9250(); initAK8963(magCalibration); pc_p->printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale)); pc_p->printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale)); if(Mscale == 0) pc_p->printf("Magnetometer resolution = 14 bits\n\r"); if(Mscale == 1) pc_p->printf("Magnetometer resolution = 16 bits\n\r"); if(Mmode == 2) pc_p->printf("Magnetometer ODR = 8 Hz\n\r"); if(Mmode == 6) pc_p->printf("Magnetometer ODR = 100 Hz\n\r"); getAres(); getGres(); getMres(); pc_p->printf("mpu9250 initialized\r\n"); return true; }else return false; } bool MPU9250::sensingAcGyMg(){ if(readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt sensingAccel(); sensingGyro(); sensingMag(); return true; }else return false; } void MPU9250::calculatePostureAngle(float degree[3]){ Now = timer.read_us(); deltat = (float)((Now - lastUpdate)/1000000.0f); // set integration time by time elapsed since last filter update lastUpdate = Now; // if(lastUpdate - firstUpdate > 10000000.0f) { // beta = 0.04; // decrease filter gain after stabilized // zeta = 0.015; // increasey bias drift gain after stabilized // } // Pass gyro rate as rad/s MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz); MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz); //my, mx, mzになってるけどセンサの設置上の都合だろうか // 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. translateQuaternionToDeg(q); calibrateDegree(); degree[0] = roll; degree[1] = pitch; degree[2] = yaw; } float MPU9250::calculateYawByMg(){ transformCoordinateFromCompassToMPU(); lpmag[0] = LPGAIN_MAG *lpmag[0] + (1 - LPGAIN_MAG)*mx; lpmag[1] = LPGAIN_MAG *lpmag[1] + (1 - LPGAIN_MAG)*my; lpmag[2] = LPGAIN_MAG *lpmag[2] + (1 - LPGAIN_MAG)*mz; float radroll = PI/180.0f * roll; float radpitch = PI/180.0f * pitch; return 180.0f/PI * atan2(lpmag[2]*sin(radpitch) - lpmag[1]*cos(radpitch), lpmag[0]*cos(radroll) - lpmag[1]*sin(radroll)*sin(radpitch) + lpmag[2]*sin(radroll)*cos(radpitch)); } // Accelerometer and gyroscope self test; check calibration wrt factory settings void MPU9250::MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass { uint8_t rawData[6] = {0, 0, 0, 0, 0, 0}; uint8_t selfTest[6]; int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3]; float factoryTrim[6]; uint8_t FS = 0; writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; } for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings aAvg[ii] /= 200; gAvg[ii] /= 200; } // Configure the accelerometer for self-test writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s //delay(55); // Delay a while to let the device stabilize for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; } for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings aSTAvg[ii] /= 200; gSTAvg[ii] /= 200; } // Configure the gyro and accelerometer for normal operation writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); //delay(45); // Delay a while to let the device stabilize // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results // Retrieve factory self-test value from self-test code reads factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response // To get percent, must multiply by 100 for (int i = 0; i < 3; i++) { destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences } } void MPU9250::pickupAccel(float accel[3]){ sensingAccel(); accel[0] = ax; accel[1] = ay; accel[2] = az; } void MPU9250::pickupGyro(float gyro[3]){ sensingGyro(); gyro[0] = gx; gyro[1] = gy; gyro[2] = gz; } void MPU9250::pickupMag(float mag[3]){ sensingMag(); mag[0] = mx; mag[1] = my; mag[2] = mz; } float MPU9250::pickupTemp(void){ sensingTemp(); return temperature; } void MPU9250::displayAccel(void){ pc_p->printf("ax = %f", 1000*ax); pc_p->printf(" ay = %f", 1000*ay); pc_p->printf(" az = %f mg\n\r", 1000*az); } void MPU9250::displayGyro(void){ pc_p->printf("gx = %f", gx); pc_p->printf(" gy = %f", gy); pc_p->printf(" gz = %f deg/s\n\r", gz); } void MPU9250::displayMag(void){ pc_p->printf("mx = %f,", mx); pc_p->printf(" my = %f,", my); pc_p->printf(" mz = %f mG\n\r", mz); } void MPU9250::displayQuaternion(void){ pc_p->printf("q0 = %f\n\r", q[0]); pc_p->printf("q1 = %f\n\r", q[1]); pc_p->printf("q2 = %f\n\r", q[2]); pc_p->printf("q3 = %f\n\r", q[3]); } void MPU9250::displayAngle(void){ //pc_p->printf("$%d %d %d;",(int)(yaw*100),(int)(pitch*100),(int)(roll*100)); pc_p->printf("Roll: %f\tPitch: %f\tYaw: %f\n\r", roll, pitch, yaw); } void MPU9250::displayTemperature(void){ pc_p->printf(" temperature = %f C\n\r", temperature); } void MPU9250::setMagBias(float bias_x, float bias_y, float bias_z){ magbias[0] = bias_x; magbias[1] = bias_y; magbias[2] = bias_z; } /*---------- private function ----------*/ void MPU9250::writeByte(uint8_t address, uint8_t subAddress, uint8_t data) { char data_write[2]; data_write[0] = subAddress; data_write[1] = data; i2c.write(address, data_write, 2, 0); } char MPU9250::readByte(uint8_t address, uint8_t subAddress) { char data[1]; // `data` will store the register data char data_write[1]; data_write[0] = subAddress; i2c.write(address, data_write, 1, 1); // no stop i2c.read(address, data, 1, 0); return data[0]; } void MPU9250::readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) { char data[14]; char data_write[1]; data_write[0] = subAddress; i2c.write(address, data_write, 1, 1); // no stop i2c.read(address, data, count, 0); for(int ii = 0; ii < count; ii++) { dest[ii] = data[ii]; } } void MPU9250::initializeValue(void){ Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR GyroMeasError = PI * (60.0f / 180.0f); beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s) zeta = sqrt(3.0f / 4.0f) * GyroMeasDrift; // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value deltat = 0.0f; // integration interval for both filter schemes lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval for(int i=0; i<3; i++){ magCalibration[i] = 0; gyroBias[i] = 0; accelBias[i] = 0; magbias[i] = 0; eInt[i] = 0.0f; lpmag[i] = 0.0f; } q[0] = 1.0f; q[1] = 0.0f; q[2] = 0.0f; q[3] = 0.0f; } void MPU9250::initMPU9250(void) { // Initialize MPU9250 device // wake up device writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt // get stable time source writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001 // Configure Gyro and Accelerometer // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively; // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate writeByte(MPU9250_ADDRESS, CONFIG, 0x03); // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV) writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above // Set gyroscope full scale range // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG); // get current GYRO_CONFIG register value // c = c & ~0xE0; // Clear self-test bits [7:5] c = c & ~0x02; // Clear Fchoice bits [1:0] c = c & ~0x18; // Clear AFS bits [4:3] c = c | Gscale << 3; // Set full scale range for the gyro // c =| 0x00; // Set Fchoice for the gyro to 11 by writing its inverse to bits 1:0 of GYRO_CONFIG writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c ); // Write new GYRO_CONFIG value to register // Set accelerometer full-scale range configuration c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG); // get current ACCEL_CONFIG register value // c = c & ~0xE0; // Clear self-test bits [7:5] c = c & ~0x18; // Clear AFS bits [4:3] c = c | Ascale << 3; // Set full scale range for the accelerometer writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c); // Write new ACCEL_CONFIG register value // Set accelerometer sample rate configuration // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2); // get current ACCEL_CONFIG2 register value c = c & ~0x0F; // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0]) c = c | 0x03; // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c); // Write new ACCEL_CONFIG2 register value // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates, // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting // Configure Interrupts and Bypass Enable // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips // can join the I2C bus and all can be controlled by the Arduino as master writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22); writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt } void MPU9250::initAK8963(float * destination) { // First extract the factory calibration for each magnetometer axis uint8_t rawData[3]; // x/y/z gyro calibration data stored here writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer wait(0.01); writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode wait(0.01); readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc. destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f; destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f; writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer wait(0.01); // Configure the magnetometer for continuous read and highest resolution // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register, // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR wait(0.01); } void MPU9250::resetMPU9250(void) { // reset device writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device wait(0.1); } // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers. void MPU9250::calibrateMPU9250(float * dest1, float * dest2) { uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data uint16_t ii, packet_count, fifo_count; int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0}; int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases // reset device, reset all registers, clear gyro and accelerometer bias registers writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device wait(0.1); // get stable time source // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00); wait(0.2); // Configure device for bias calculation writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP wait(0.015); // Configure MPU9250 gyro and accelerometer for bias calculation writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec uint16_t accelsensitivity = 16384; // = 16384 LSB/g // Configure FIFO to capture accelerometer and gyro data for bias calculation writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250) wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes // At end of sample accumulation, turn off FIFO sensor read writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count fifo_count = ((uint16_t)data[0] << 8) | data[1]; packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging for (ii = 0; ii < packet_count; ii++) { int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0}; readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ; accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ; gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ; gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ; gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ; accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases accel_bias[1] += (int32_t) accel_temp[1]; accel_bias[2] += (int32_t) accel_temp[2]; gyro_bias[0] += (int32_t) gyro_temp[0]; gyro_bias[1] += (int32_t) gyro_temp[1]; gyro_bias[2] += (int32_t) gyro_temp[2]; } accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases accel_bias[1] /= (int32_t) packet_count; accel_bias[2] /= (int32_t) packet_count; gyro_bias[0] /= (int32_t) packet_count; gyro_bias[1] /= (int32_t) packet_count; gyro_bias[2] /= (int32_t) packet_count; if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation else {accel_bias[2] += (int32_t) accelsensitivity;} // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup data[0] = (-gyro_bias[0]/4 >> 8) & 0xFF; // Divide by 4 to get 32.9 LSB per deg/s to conform to expected bias input format data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF; data[3] = (-gyro_bias[1]/4) & 0xFF; data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF; data[5] = (-gyro_bias[2]/4) & 0xFF; /// Push gyro biases to hardware registers /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]); writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]); writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]); writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]); writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]); writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]); */ dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity; dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity; // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that // the accelerometer biases calculated above must be divided by 8. readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1]; readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]); accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1]; readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]); accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1]; uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis for(ii = 0; ii < 3; ii++) { if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit } // Construct total accelerometer bias, including calculated average accelerometer bias from above accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale) accel_bias_reg[1] -= (accel_bias[1]/8); accel_bias_reg[2] -= (accel_bias[2]/8); data[0] = (accel_bias_reg[0] >> 8) & 0xFF; data[1] = (accel_bias_reg[0]) & 0xFF; data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[2] = (accel_bias_reg[1] >> 8) & 0xFF; data[3] = (accel_bias_reg[1]) & 0xFF; data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[4] = (accel_bias_reg[2] >> 8) & 0xFF; data[5] = (accel_bias_reg[2]) & 0xFF; data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers // Apparently this is not working for the acceleration biases in the MPU-9250 // Are we handling the temperature correction bit properly? // Push accelerometer biases to hardware registers /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]); writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]); writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]); writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]); writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]); writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]); */ // Output scaled accelerometer biases for manual subtraction in the main program dest2[0] = (float)accel_bias[0]/(float)accelsensitivity; dest2[1] = (float)accel_bias[1]/(float)accelsensitivity; dest2[2] = (float)accel_bias[2]/(float)accelsensitivity; } void MPU9250::getMres(void) { switch (Mscale) { // Possible magnetometer scales (and their register bit settings) are: // 14 bit resolution (0) and 16 bit resolution (1) case MFS_14BITS: mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss break; case MFS_16BITS: mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss break; } } void MPU9250::getGres(void) { switch (Gscale) { // Possible gyro scales (and their register bit settings) are: // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11). // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: case GFS_250DPS: gRes = 250.0/32768.0; break; case GFS_500DPS: gRes = 500.0/32768.0; break; case GFS_1000DPS: gRes = 1000.0/32768.0; break; case GFS_2000DPS: gRes = 2000.0/32768.0; break; } } void MPU9250::getAres(void) { switch (Ascale) { // Possible accelerometer scales (and their register bit settings) are: // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11). // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: case AFS_2G: aRes = 2.0/32768.0; break; case AFS_4G: aRes = 4.0/32768.0; break; case AFS_8G: aRes = 8.0/32768.0; break; case AFS_16G: aRes = 16.0/32768.0; break; } } void MPU9250::readAccelData(int16_t * destination) { uint8_t rawData[6]; // x/y/z accel register data stored here readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; } void MPU9250::readGyroData(int16_t * destination) { uint8_t rawData[6]; // x/y/z gyro register data stored here readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; } void MPU9250::readMagData(int16_t * destination) { uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array uint8_t c = rawData[6]; // End data read by reading ST2 register if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ; } } } int16_t MPU9250::readTempData(void) { uint8_t rawData[2]; // x/y/z gyro register data stored here readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value } uint8_t MPU9250::Whoami_MPU9250(void){ return readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); } uint8_t MPU9250::Whoami_AK8963(void){ return readByte(WHO_AM_I_AK8963, WHO_AM_I_AK8963); } void MPU9250::sensingAccel(void){ readAccelData(accelCount); ax = (float)accelCount[0]*aRes - accelBias[0]; ay = (float)accelCount[1]*aRes - accelBias[1]; az = (float)accelCount[2]*aRes - accelBias[2]; } void MPU9250::sensingGyro(void){ readGyroData(gyroCount); gx = (float)gyroCount[0]*gRes - gyroBias[0]; gy = (float)gyroCount[1]*gRes - gyroBias[1]; gz = (float)gyroCount[2]*gRes - gyroBias[2]; } void MPU9250::sensingMag(void){ readMagData(magCount); mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]; my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1]; mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2]; } void MPU9250::sensingTemp(void){ tempCount = readTempData(); temperature = ((float) tempCount) / 333.87f + 21.0f; // Temperature in degrees Centigrade } // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays" // (see http://www.x-io.co.uk/category/open-source/ for examples and more details) // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc. // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz! void MPU9250::MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) { float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability float norm; float hx, hy, _2bx, _2bz; float s1, s2, s3, s4; float qDot1, qDot2, qDot3, qDot4; // Auxiliary variables to avoid repeated arithmetic float _2q1mx; float _2q1my; float _2q1mz; float _2q2mx; float _4bx; float _4bz; float _2q1 = 2.0f * q1; float _2q2 = 2.0f * q2; float _2q3 = 2.0f * q3; float _2q4 = 2.0f * q4; float _2q1q3 = 2.0f * q1 * q3; float _2q3q4 = 2.0f * q3 * q4; float q1q1 = q1 * q1; float q1q2 = q1 * q2; float q1q3 = q1 * q3; float q1q4 = q1 * q4; float q2q2 = q2 * q2; float q2q3 = q2 * q3; float q2q4 = q2 * q4; float q3q3 = q3 * q3; float q3q4 = q3 * q4; float q4q4 = q4 * q4; // Normalise accelerometer measurement norm = sqrt(ax * ax + ay * ay + az * az); if (norm == 0.0f) return; // handle NaN norm = 1.0f/norm; ax *= norm; ay *= norm; az *= norm; // Normalise magnetometer measurement norm = sqrt(mx * mx + my * my + mz * mz); if (norm == 0.0f) return; // handle NaN norm = 1.0f/norm; mx *= norm; my *= norm; mz *= norm; // Reference direction of Earth's magnetic field _2q1mx = 2.0f * q1 * mx; _2q1my = 2.0f * q1 * my; _2q1mz = 2.0f * q1 * mz; _2q2mx = 2.0f * q2 * mx; hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4; hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4; _2bx = sqrt(hx * hx + hy * hy); _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4; _4bx = 2.0f * _2bx; _4bz = 2.0f * _2bz; // Gradient decent algorithm corrective step s1 = -_2q3 * (2.0f * q2q4 - _2q1q3 - ax) + _2q2 * (2.0f * q1q2 + _2q3q4 - ay) - _2bz * q3 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q4 + _2bz * q2) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q3 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); s2 = _2q4 * (2.0f * q2q4 - _2q1q3 - ax) + _2q1 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q2 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + _2bz * q4 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q3 + _2bz * q1) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q4 - _4bz * q2) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); s3 = -_2q1 * (2.0f * q2q4 - _2q1q3 - ax) + _2q4 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q3 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + (-_4bx * q3 - _2bz * q1) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q2 + _2bz * q4) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q1 - _4bz * q3) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); s4 = _2q2 * (2.0f * q2q4 - _2q1q3 - ax) + _2q3 * (2.0f * q1q2 + _2q3q4 - ay) + (-_4bx * q4 + _2bz * q2) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q1 + _2bz * q3) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q2 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude norm = 1.0f/norm; s1 *= norm; s2 *= norm; s3 *= norm; s4 *= norm; // Compute rate of change of quaternion qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1; qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2; qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3; qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4; // Integrate to yield quaternion q1 += qDot1 * deltat; q2 += qDot2 * deltat; q3 += qDot3 * deltat; q4 += qDot4 * deltat; norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion norm = 1.0f/norm; q[0] = q1 * norm; q[1] = q2 * norm; q[2] = q3 * norm; q[3] = q4 * norm; } void MPU9250::MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) { float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability float norm; float hx, hy, bx, bz; float vx, vy, vz, wx, wy, wz; float ex, ey, ez; float pa, pb, pc; // Auxiliary variables to avoid repeated arithmetic float q1q1 = q1 * q1; float q1q2 = q1 * q2; float q1q3 = q1 * q3; float q1q4 = q1 * q4; float q2q2 = q2 * q2; float q2q3 = q2 * q3; float q2q4 = q2 * q4; float q3q3 = q3 * q3; float q3q4 = q3 * q4; float q4q4 = q4 * q4; // Normalise accelerometer measurement norm = sqrt(ax * ax + ay * ay + az * az); if (norm == 0.0f) return; // handle NaN norm = 1.0f / norm; // use reciprocal for division ax *= norm; ay *= norm; az *= norm; // Normalise magnetometer measurement norm = sqrt(mx * mx + my * my + mz * mz); if (norm == 0.0f) return; // handle NaN norm = 1.0f / norm; // use reciprocal for division mx *= norm; my *= norm; mz *= norm; // Reference direction of Earth's magnetic field hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3); hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2); bx = sqrt((hx * hx) + (hy * hy)); bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3); // Estimated direction of gravity and magnetic field vx = 2.0f * (q2q4 - q1q3); vy = 2.0f * (q1q2 + q3q4); vz = q1q1 - q2q2 - q3q3 + q4q4; wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3); wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4); wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3); // Error is cross product between estimated direction and measured direction of gravity ex = (ay * vz - az * vy) + (my * wz - mz * wy); ey = (az * vx - ax * vz) + (mz * wx - mx * wz); ez = (ax * vy - ay * vx) + (mx * wy - my * wx); if (Ki > 0.0f){ eInt[0] += ex; // accumulate integral error eInt[1] += ey; eInt[2] += ez; }else{ eInt[0] = 0.0f; // prevent integral wind up eInt[1] = 0.0f; eInt[2] = 0.0f; } // Apply feedback terms gx = gx + Kp * ex + Ki * eInt[0]; gy = gy + Kp * ey + Ki * eInt[1]; gz = gz + Kp * ez + Ki * eInt[2]; // Integrate rate of change of quaternion pa = q2; pb = q3; pc = q4; q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat); q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat); q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat); q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat); // Normalise quaternion norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); norm = 1.0f / norm; q[0] = q1 * norm; q[1] = q2 * norm; q[2] = q3 * norm; q[3] = q4 * norm; } void MPU9250::translateQuaternionToDeg(float quaternion[4]){ yaw = atan2(2.0f * (quaternion[1] * quaternion[2] + quaternion[0] * quaternion[3]), quaternion[0] * quaternion[0] + quaternion[1] * quaternion[1] - quaternion[2] * quaternion[2] - quaternion[3] * quaternion[3]); roll = -asin(2.0f * (quaternion[1] * quaternion[3] - quaternion[0] * quaternion[2])); pitch = atan2(2.0f * (quaternion[0] * quaternion[1] + quaternion[2] * quaternion[3]), quaternion[0] * quaternion[0] - quaternion[1] * quaternion[1] - quaternion[2] * quaternion[2] + quaternion[3] * quaternion[3]); } void MPU9250::calibrateDegree(void){ pitch *= 180.0f / PI; yaw *= 180.0f / PI; yaw -= DECLINATION; roll *= 180.0f / PI; } void MPU9250::transformCoordinateFromCompassToMPU(){ float buf = mx; mx = my; my = buf; mz = -mz; }