MPU9150Lib.cpp

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//
//  This file is part of MPU9150Lib
//
//  Copyright (c) 2013 Pansenti, LLC
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy of 
//  this software and associated documentation files (the "Software"), to deal in 
//  the Software without restriction, including without limitation the rights to use, 
//  copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the 
//  Software, and to permit persons to whom the Software is furnished to do so, 
//  subject to the following conditions:
//
//  The above copyright notice and this permission notice shall be included in all 
//  copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
//  INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 
//  PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 
//  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
//  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 
//  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

#include "MPU9150Lib.h"
#include "inv_mpu.h"
#include "inv_mpu_dmp_motion_driver.h"
#include "MPUQuaternion.h"

//
//  The functions below are from the InvenSense SDK example code.
//
//  Original copyright notice below:

/*
 $License:
    Copyright (C) 2011-2012 InvenSense Corporation, All Rights Reserved.
    See included License.txt for License information.
 $
 */

/* These next two functions converts the orientation matrix (see
 * gyro_orientation) to a scalar representation for use by the DMP.
 * NOTE: These functions are borrowed from InvenSense's MPL.
 */

static inline unsigned short inv_row_2_scale(const signed char *row)
{
    unsigned short b;

    if (row[0] > 0)
        b = 0;
    else if (row[0] < 0)
        b = 4;
    else if (row[1] > 0)
        b = 1;
    else if (row[1] < 0)
        b = 5;
    else if (row[2] > 0)
        b = 2;
    else if (row[2] < 0)
        b = 6;
    else
        b = 7;      // error
    return b;
}

/* The sensors can be mounted onto the board in any orientation. The mounting
 * matrix seen below tells the MPL how to rotate the raw data from thei
 * driver(s).
 * TODO: The following matrices refer to the configuration on an internal test
 * board at Invensense. If needed, please modify the matrices to match the
 * chip-to-body matrix for your particular set up.
 */

static signed char gyro_orientation[9] = { 1, 0, 0,
                                           0, 1, 0,
                                           0, 0, 1};

static inline unsigned short inv_orientation_matrix_to_scalar(const signed char *mtx)
{
    unsigned short scalar;
    /*

       XYZ  010_001_000 Identity Matrix
       XZY  001_010_000
       YXZ  010_000_001
       YZX  000_010_001
       ZXY  001_000_010
       ZYX  000_001_010
     */
    scalar = inv_row_2_scale(mtx);
    scalar |= inv_row_2_scale(mtx + 3) << 3;
    scalar |= inv_row_2_scale(mtx + 6) << 6;
    return scalar;
}

//


MPU9150Lib::MPU9150Lib()
{
  //  use calibration if available

  m_useAccelCalibration = true;
  m_useMagCalibration = true;
  m_device = 0;
 }

void MPU9150Lib::selectDevice(int device)
{
  m_device = device;
}

void MPU9150Lib::useAccelCal(boolean useCal)
{
  m_useAccelCalibration = useCal;
}

void MPU9150Lib::disableAccelCal()
{
    if (!m_useAccelCalibration)
        return;
    m_useAccelCalibration = false;

    m_accelOffset[0] = 0;
    m_accelOffset[1] = 0;
    m_accelOffset[2] = 0;

    mpu_set_accel_bias(m_accelOffset);
}

void MPU9150Lib::useMagCal(boolean useCal)
{
  m_useMagCalibration = useCal;
}

boolean MPU9150Lib::init(int mpuRate, int magMix, int magRate, int lpf)
{
  struct int_param_s int_param;
  int result;

  mpu_select_device(m_device);
  dmp_select_device(m_device);
  if (magRate > 100)
    return false;                                         // rate must be less than or equal to 100Hz
  if (magRate < 1)
    return false;
  m_magInterval = (unsigned long)(1000 / magRate);        // record mag interval
  m_lastMagSample = millis();

  if (mpuRate > 1000)
    return false;
  if (mpuRate < 1)
    return false;
  m_magMix = magMix;
  m_lastDMPYaw = 0;
  m_lastYaw = 0;

  // get calibration data if it's there

  if (calLibRead(m_device, &m_calData)) {                 // use calibration data if it's there and wanted
    m_useMagCalibration &= m_calData.magValid == 1;
    m_useAccelCalibration &= m_calData.accelValid == 1;

    //  Process calibration data for runtime

    if (m_useMagCalibration) {
       m_magXOffset = (short)(((long)m_calData.magMaxX + (long)m_calData.magMinX) / 2);
       m_magXRange = m_calData.magMaxX - m_magXOffset;
       m_magYOffset = (short)(((long)m_calData.magMaxY + (long)m_calData.magMinY) / 2);
       m_magYRange = m_calData.magMaxY - m_magYOffset;
       m_magZOffset = (short)(((long)m_calData.magMaxZ + (long)m_calData.magMinZ) / 2);
       m_magZRange = m_calData.magMaxZ - m_magZOffset;
    }

     if (m_useAccelCalibration) {
       m_accelOffset[0] = -((long)m_calData.accelMaxX + (long)m_calData.accelMinX) / 2;
       m_accelOffset[1] = -((long)m_calData.accelMaxY + (long)m_calData.accelMinY) / 2;
       m_accelOffset[2] = -((long)m_calData.accelMaxZ + (long)m_calData.accelMinZ) / 2;

       mpu_set_accel_bias(m_accelOffset);

       m_accelXRange = m_calData.accelMaxX + (short)m_accelOffset[0];
       m_accelYRange = m_calData.accelMaxY + (short)m_accelOffset[1];
       m_accelZRange = m_calData.accelMaxZ + (short)m_accelOffset[2];
     }
  } else {
      m_useMagCalibration = false;
      m_useAccelCalibration = false;
  }

#ifdef MPULIB_DEBUG
  if (m_useMagCalibration)
          Serial.println("Using mag cal");
  if (m_useAccelCalibration)
          Serial.println("Using accel cal");
#endif

  mpu_init_structures();
    
  // Not using interrupts so set up this structure to keep the driver happy
        
  int_param.cb = NULL;
  int_param.pin = 0;
  int_param.lp_exit = 0;
  int_param.active_low = 1;
  result = mpu_init(&int_param);
  if (result != 0) {
#ifdef MPULIB_DEBUG
     Serial.print("mpu_init failed with code: "); Serial.println(result);
#endif
     return false; 
  }
  mpu_set_sensors(INV_XYZ_GYRO | INV_XYZ_ACCEL | INV_XYZ_COMPASS);   // enable all of the sensors
  mpu_configure_fifo(INV_XYZ_GYRO | INV_XYZ_ACCEL);                  // get accel and gyro data in the FIFO also

#ifdef MPULIB_DEBUG
  Serial.println("Loading firmware");
#endif

  if ((result = dmp_load_motion_driver_firmware()) != 0) {           // try to load the DMP firmware
#ifdef MPULIB_DEBUG
    Serial.print("Failed to load dmp firmware: ");
    Serial.println(result);
#endif
    return false;
  }
  dmp_set_orientation(inv_orientation_matrix_to_scalar(gyro_orientation)); // set up the correct orientation

  dmp_enable_feature(DMP_FEATURE_6X_LP_QUAT | DMP_FEATURE_SEND_RAW_ACCEL | DMP_FEATURE_SEND_CAL_GYRO |
        DMP_FEATURE_GYRO_CAL);
  dmp_set_fifo_rate(mpuRate);
  if (mpu_set_dmp_state(1) != 0) {
#ifdef MPULIB_DEBUG
    Serial.println("mpu_set_dmp_state failed");
#endif
    return false;
  }
  mpu_set_sample_rate(mpuRate);                                      // set the update rate
  mpu_set_compass_sample_rate(magRate);                              // set the compass update rate to match
  if (lpf != 0)
    mpu_set_lpf(lpf);                                                // set the low pass filter
  return true;
}

boolean MPU9150Lib::read()
{
    short intStatus;
    int result;
    short sensors;
    unsigned char more;
    unsigned long timestamp;
   
    mpu_select_device(m_device);
    dmp_select_device(m_device);
    mpu_get_int_status(&intStatus);                       // get the current MPU state
    if ((intStatus & (MPU_INT_STATUS_DMP | MPU_INT_STATUS_DMP_0))
            != (MPU_INT_STATUS_DMP | MPU_INT_STATUS_DMP_0))
        return false;
        
    //  get the data from the fifo
        
    if ((result = dmp_read_fifo(m_rawGyro, m_rawAccel, m_rawQuaternion, &timestamp, &sensors, &more)) != 0) {
      return false;
    }      
    
    //  got the fifo data so now get the mag data if it's time
    
    if ((millis() - m_lastMagSample) >= m_magInterval) {
      if ((result = mpu_get_compass_reg(m_rawMag, &timestamp)) != 0) {
#ifdef MPULIB_DEBUG
        Serial.print("Failed to read compass: ");
        Serial.println(result);
#endif
        return false;
      }
      //        *** Note mag axes are changed here to align with gyros: Y = -X, X = Y

      m_lastMagSample = millis();

      if (m_useMagCalibration) {
        m_calMag[VEC3_Y] = -(short)(((long)(m_rawMag[VEC3_X] - m_magXOffset) * (long)SENSOR_RANGE) / (long)m_magXRange);
        m_calMag[VEC3_X] = (short)(((long)(m_rawMag[VEC3_Y] - m_magYOffset) * (long)SENSOR_RANGE) / (long)m_magYRange);
        m_calMag[VEC3_Z] = (short)(((long)(m_rawMag[VEC3_Z] - m_magZOffset) * (long)SENSOR_RANGE) / (long)m_magZRange);
      } else {
        m_calMag[VEC3_Y] = -m_rawMag[VEC3_X];
        m_calMag[VEC3_X] = m_rawMag[VEC3_Y];
        m_calMag[VEC3_Z] = m_rawMag[VEC3_Z];
      }
    }
    
    // got the raw data - now process
    
    m_dmpQuaternion[QUAT_W] = (float)m_rawQuaternion[QUAT_W];  // get float version of quaternion
    m_dmpQuaternion[QUAT_X] = (float)m_rawQuaternion[QUAT_X];
    m_dmpQuaternion[QUAT_Y] = (float)m_rawQuaternion[QUAT_Y];
    m_dmpQuaternion[QUAT_Z] = (float)m_rawQuaternion[QUAT_Z];
    MPUQuaternionNormalize(m_dmpQuaternion);                 // and normalize
    
    MPUQuaternionQuaternionToEuler(m_dmpQuaternion, m_dmpEulerPose);


    // Scale accel data 

    if (m_useAccelCalibration) {
/*        m_calAccel[VEC3_X] = -(short)((((long)m_rawAccel[VEC3_X] + m_accelOffset[0])
                                        * (long)SENSOR_RANGE) / (long)m_accelXRange);
        m_calAccel[VEC3_Y] = (short)((((long)m_rawAccel[VEC3_Y] + m_accelOffset[1])
                                        * (long)SENSOR_RANGE) / (long)m_accelYRange);
        m_calAccel[VEC3_Z] = (short)((((long)m_rawAccel[VEC3_Z] + m_accelOffset[2])
                                        * (long)SENSOR_RANGE) / (long)m_accelZRange);
*/        if (m_rawAccel[VEC3_X] >= 0)
            m_calAccel[VEC3_X] = -(short)((((long)m_rawAccel[VEC3_X])
                                        * (long)SENSOR_RANGE) / (long)m_calData.accelMaxX);
        else
            m_calAccel[VEC3_X] = -(short)((((long)m_rawAccel[VEC3_X])
                                        * (long)SENSOR_RANGE) / -(long)m_calData.accelMinX);

        if (m_rawAccel[VEC3_Y] >= 0)
            m_calAccel[VEC3_Y] = (short)((((long)m_rawAccel[VEC3_Y])
                                        * (long)SENSOR_RANGE) / (long)m_calData.accelMaxY);
        else
            m_calAccel[VEC3_Y] = (short)((((long)m_rawAccel[VEC3_Y])
                                        * (long)SENSOR_RANGE) / -(long)m_calData.accelMinY);

        if (m_rawAccel[VEC3_Z] >= 0)
            m_calAccel[VEC3_Z] = (short)((((long)m_rawAccel[VEC3_Z])
                                        * (long)SENSOR_RANGE) / (long)m_calData.accelMaxZ);
        else
            m_calAccel[VEC3_Z] = (short)((((long)m_rawAccel[VEC3_Z])
                                        * (long)SENSOR_RANGE) / -(long)m_calData.accelMinZ);

    } else {
      m_calAccel[VEC3_X] = -m_rawAccel[VEC3_X];
      m_calAccel[VEC3_Y] = m_rawAccel[VEC3_Y];
      m_calAccel[VEC3_Z] = m_rawAccel[VEC3_Z];
    }
    dataFusion();
    return true;
}

void MPU9150Lib::dataFusion()
{
  float qMag[4];
  float deltaDMPYaw, deltaMagYaw;
  float newMagYaw, newYaw;
  float temp1[4], unFused[4];
  float unFusedConjugate[4];

  // *** NOTE *** pitch direction swapped here

  m_fusedEulerPose[VEC3_X] = m_dmpEulerPose[VEC3_X];
  m_fusedEulerPose[VEC3_Y] = -m_dmpEulerPose[VEC3_Y];
  m_fusedEulerPose[VEC3_Z] = 0; 
  MPUQuaternionEulerToQuaternion(m_fusedEulerPose, unFused);    // create a new quaternion

  deltaDMPYaw = -m_dmpEulerPose[VEC3_Z] + m_lastDMPYaw;         // calculate change in yaw from dmp
  m_lastDMPYaw = m_dmpEulerPose[VEC3_Z];                        // update that
 
  qMag[QUAT_W] = 0;
  qMag[QUAT_X] = m_calMag[VEC3_X];
  qMag[QUAT_Y] = m_calMag[VEC3_Y];
  qMag[QUAT_Z] = m_calMag[VEC3_Z];
        
  // Tilt compensate mag with the unfused data (i.e. just roll and pitch with yaw 0)
        
  MPUQuaternionConjugate(unFused, unFusedConjugate);
  MPUQuaternionMultiply(qMag, unFusedConjugate, temp1);
  MPUQuaternionMultiply(unFused, temp1, qMag);

  // Now fuse this with the dmp yaw gyro information

  newMagYaw = -atan2(qMag[QUAT_Y], qMag[QUAT_X]);

  if (newMagYaw != newMagYaw) {                                 // check for nAn
#ifdef MPULIB_DEBUG
    Serial.println("***nAn\n");
#endif
    return;                                                     // just ignore in this case
  }
  if (newMagYaw < 0)
    newMagYaw = 2.0f * (float)M_PI + newMagYaw;                 // need 0 <= newMagYaw <= 2*PI

  newYaw = m_lastYaw + deltaDMPYaw;                             // compute new yaw from change

  if (newYaw > (2.0f * (float)M_PI))                            // need 0 <= newYaw <= 2*PI
    newYaw -= 2.0f * (float)M_PI;
  if (newYaw < 0)
    newYaw += 2.0f * (float)M_PI;

  deltaMagYaw = newMagYaw - newYaw;                             // compute difference

  if (deltaMagYaw >= (float)M_PI)
    deltaMagYaw = deltaMagYaw - 2.0f * (float)M_PI;
  if (deltaMagYaw <= -(float)M_PI)
    deltaMagYaw = (2.0f * (float)M_PI + deltaMagYaw);

  if (m_magMix > 0) {
    newYaw += deltaMagYaw / m_magMix;                           // apply some of the correction

    if (newYaw > (2.0f * (float)M_PI))                                      // need 0 <= newYaw <= 2*PI
      newYaw -= 2.0f * (float)M_PI;
    if (newYaw < 0)
      newYaw += 2.0f * (float)M_PI;
  }

  m_lastYaw = newYaw;

  if (newYaw > (float)M_PI)
    newYaw -= 2.0f * (float)M_PI;

  m_fusedEulerPose[VEC3_Z] = newYaw;                            // fill in output yaw value
        
  MPUQuaternionEulerToQuaternion(m_fusedEulerPose, m_fusedQuaternion);
}

void MPU9150Lib::printQuaternion(long *quat)
{
  Serial.print("w: "); Serial.print(quat[QUAT_W]);  
  Serial.print(" x: "); Serial.print(quat[QUAT_X]);  
  Serial.print(" y: "); Serial.print(quat[QUAT_Y]);  
  Serial.print(" z: "); Serial.print(quat[QUAT_Z]);  
}

void MPU9150Lib::printQuaternion(float *quat)
{
  Serial.print("w: "); Serial.print(quat[QUAT_W]);  
  Serial.print(" x: "); Serial.print(quat[QUAT_X]);  
  Serial.print(" y: "); Serial.print(quat[QUAT_Y]);  
  Serial.print(" z: "); Serial.print(quat[QUAT_Z]);  
}

void MPU9150Lib::printVector(short *vec)
{
  Serial.print("x: "); Serial.print(vec[VEC3_X]);  
  Serial.print(" y: "); Serial.print(vec[VEC3_Y]);  
  Serial.print(" z: "); Serial.print(vec[VEC3_Z]);    
}

void MPU9150Lib::printVector(float *vec)
{
  Serial.print("x: "); Serial.print(vec[VEC3_X]);  
  Serial.print(" y: "); Serial.print(vec[VEC3_Y]);  
  Serial.print(" z: "); Serial.print(vec[VEC3_Z]);    
}

void MPU9150Lib::printAngles(float *vec)
{
  Serial.print("x: "); Serial.print(vec[VEC3_X] * RAD_TO_DEGREE);  
  Serial.print(" y: "); Serial.print(vec[VEC3_Y] * RAD_TO_DEGREE);  
  Serial.print(" z: "); Serial.print(vec[VEC3_Z] * RAD_TO_DEGREE);    
}