Re: [Paparazzi-devel] drotek 10dof v2 imu

[Chris]

Hi Felix.
I wan't to help as much as i can.
I use the Twog with the master branch.
The drotek imu i have has at least the "Y" mislabeled on the pcb it 
looks 180 degrees to the other side because when i checked the raw 
readings without applying any signs on them i found that it was needed 
to negate the y axis.
I have installed the imu with the solder pad row facing the back of the 
airplane and the ic side up.
If you need more data let me know.
Chris

Here is the git branch i follow:
address@hidden:~/paparazzi$ git remote show origin
* remote origin
  Fetch URL: https://github.com/paparazzi/paparazzi.git
  Push  URL: https://github.com/paparazzi/paparazzi.git
  HEAD branch: master
  Remote branches:
    ahrs_int_cmpl_quat_correction_scaling tracked
    airframe_editor                       tracked
    campaign2011                          tracked
    campaign2013                          tracked
    feature4_fixedwing_in_rotor           tracked
    imu_drotek                            new (next fetch will store in 
remotes/origin)
    master                                tracked
    mavlink                               tracked
    messages                              tracked
    px4                                   tracked
    quadshot_integration                  tracked
    refs/remotes/origin/aspirin_improved  stale (use 'git remote prune' 
to remove)
    refs/remotes/origin/mpu60x0           stale (use 'git remote prune' 
to remove)
    refs/remotes/origin/stm32f4           stale (use 'git remote prune' 
to remove)
    telemetry                             tracked
    transitioning_vehicles                tracked
    v4.0                                  tracked
    v4.2                                  tracked
    v5.0                                  tracked
  Local branch configured for 'git pull':
    master merges with remote master
  Local ref configured for 'git push':
    master pushes to master (local out of date)
address@hidden:~/paparazzi$

Here is the warnings i get from the paparazzi center:

CC 
/home/hendrix/paparazzi/var/Cessna_182/ap/subsystems/imu/imu_drotek_10dof_v2.o
subsystems/imu/imu_drotek_10dof_v2.c: In function 
'imu_drotek2_configure_mag_slave':
subsystems/imu/imu_drotek_10dof_v2.c:119:57: warning: unused parameter 
'mpu_set' [-Wunused-parameter]
subsystems/imu/imu_drotek_10dof_v2.c:119:72: warning: unused parameter 
'mpu' [-Wunused-parameter]
CC /home/hendrix/paparazzi/var/Cessna_182/ap/peripherals/mpu60x0.o
CC /home/hendrix/paparazzi/var/Cessna_182/ap/peripherals/mpu60x0_i2c.o
peripherals/mpu60x0_i2c.c: In function 'mpu60x0_i2c_event':
peripherals/mpu60x0_i2c.c:100:33: warning: cast discards 
'__attribute__((noreturn))' qualifier from pointer target type [-Wcast-qual]

Here is the relevant airframe part:

<airframe name="Cessna_182_twog.xml">

<firmware name="fixedwing">

<target name="ap"             board="twog_1.0"/>
<target name="sim"             board="pc"/>

    <configure name="SYS_TIME_LED" value="1"/>
    <configure name="GPS_LED" value="2"/>
     <define name="USE_LED_1"/>
    <define name="USE_LED_2"/>
    <define name="USE_LED_3"/>
    <define name="USE_LED_4"/>
    <define name="USE_LED_5"/>
        <define name="AGR_CLIMB"/>
    <define name="WIND_INFO"/>
    <define name="WIND_INFO_RET"/>
    <define name="STRONG_WIND"/>
    <define name="ALT_KALMAN"/>
    <define name="USE_I2C"/>
    <define name="USE_I2C0"/>
    <define name="SENSOR_SYNC_SEND"/>
    <define name="USE_AHRS_GPS_ACCELERATIONS"/>
    <define name="USE_GROUNDSPEED_CONTROL"/>
<!--
    <configure name="PERIODIC_FREQUENCY" value="120"/>
    <configure name="AHRS_PROPAGATE_FREQUENCY" value="100"/>
    <configure name="AHRS_CORRECT_FREQUENCY" value="100"/>
-->
<!--    <define name="ADC_CHANNEL_VSUPPLY" value="ADC_1" />  -->
<!--    <define name="MEASURE_AIRSPEED"/>  -->
<!--    <define name="USE_AIRSPEED"/>  -->
<!--    <define name="USE_BAROMETER"/>  -->
<!--    <define name="USE_INS_NAV_INIT" value=FALSE"/> --> <!--Set Home 
to flight plan coordinates -->


    <subsystem name="telemetry" type="transparent">
    <configure name="MODEM_BAUD" value="B115200"/>
<!--    <configure name="MODEM_PORT" value="UART2"/> -->
<!--    <configure name="MODEM_LED"  value="5"/>  -->
        </subsystem>
        <subsystem name="gps" type="ublox">
    <configure name="GPS_BAUD"          value="B38400"/>
<!--    <configure name="GPS_PORT" value="UART3"/>  -->
<!--    <configure name="GPS_LED"           value="none"/> -->
        </subsystem>

    <subsystem name="control" />
    <subsystem name="radio_control" type="ppm"/>
    <subsystem name="navigation" type="extra"/>

    <subsystem name="imu"    type="drotek_10dof_v2">
        <configure name="DROTEK_2_I2C_DEV" value="i2c0"/>
    </subsystem>

    <!-- MAGNETOMETER IS NOT WORKING IN DCM BE CAREFULL -->
        <subsystem name="ahrs" type="float_dcm">
        <define name="USE_MAGNETOMETER" value="0"/>
        <define name="USE_MAGNETOMETER_ONGROUND" value="0"/>
        </subsystem>

    <subsystem name="ins" type="alt_float"/>
</firmware>

<section name="AHRS" prefix="AHRS_" >
    <define name="H_X" value="(26536.9/45821.6)" />
    <define name="H_Y" value="(1850.1/45821.6)" />
    <define name="H_Z" value="(37309.3/45821.6) " />
    <define name="MAG_DECLINATION" value="(RadOfDeg(4))" />
</section>

<section name="IMU" prefix="IMU_">
    <define name="GYRO_P_SIGN" value="1"/>
    <define name="GYRO_Q_SIGN" value="1"/>
    <define name="GYRO_R_SIGN" value="1"/>

    <define name="ACCEL_X_SIGN" value="1"/>
    <define name="ACCEL_Y_SIGN" value="1"/>
    <define name="ACCEL_Z_SIGN" value="1"/>

    <define name="MAG_X_SIGN" value="1"/>
    <define name="MAG_Y_SIGN" value="1"/>
    <define name="MAG_Z_SIGN" value="1"/>

    <define name="BODY_TO_IMU_PHI" value="0" unit="deg"/>
    <define name="BODY_TO_IMU_THETA" value="0" unit="deg"/>
    <define name="BODY_TO_IMU_PSI" value="0" unit="deg"/>

    <!-- SENS=16.4 LSB/(deg/sec)*57.295779513 deg/rad=939.65078 
LSB/rad/sec / 12bit FRAC: 4096/939.65 -->
    <define name="GYRO_P_SENS" value="4.359" integer="16"/>
    <define name="GYRO_Q_SENS" value="4.359" integer="16"/>
    <define name="GYRO_R_SENS" value="4.359" integer="16"/>

    <define name="GYRO_P_Q" value="0."/>
    <define name="GYRO_P_R" value="0"/>
    <define name="GYRO_Q_P" value="0."/>
    <define name="GYRO_Q_R" value="0."/>
    <define name="GYRO_R_P" value="0."/>
    <define name="GYRO_R_Q" value="0."/>

    <!-- Found with calibrate.py script and visual observation of the 
RAW values -->
    <define name="ACCEL_X_NEUTRAL" value="72"/>
    <define name="ACCEL_Y_NEUTRAL" value="2"/>
    <define name="ACCEL_Z_NEUTRAL" value="-70"/>

<!-- SENS = 2048 LSB/g / 9.81 ms2/g = 208.766564729 LSB/ms2 / 10bit 
FRAC: 1024 / 208.7665 -->
    <!-- Found with calibrate.py script -->
    <define name="ACCEL_X_SENS" value="4.87542830698" integer="16"/>
    <define name="ACCEL_Y_SENS" value="4.89064537368" integer="16"/>
    <define name="ACCEL_Z_SENS" value="4.81527520369" integer="16"/>

    <!-- Found with calibrate.py script -->
    <define name="MAG_X_NEUTRAL" value="73"/>
    <define name="MAG_Y_NEUTRAL" value="118"/>
    <define name="MAG_Z_NEUTRAL" value="169"/>

    <define name="MAG_X_SENS" value="4.25741044617" integer="16"/>
    <define name="MAG_Y_SENS" value="4.26451705702" integer="16"/>
    <define name="MAG_Z_SENS" value="4.87790997442" integer="16"/>

</section>

Here is the part of my driver that assigns the values to the imu 
structure when the imu is positioned with the solder pad row facing the 
airplane's tail and the IC's  are facing up.
(all signs in the airframe are set to "1")
#define MPU_OFFSET_ACC 1
      x = (int16_t) ((mpu60x0_trans.buf[0+MPU_OFFSET_ACC] << 8) | 
mpu60x0_trans.buf[1+MPU_OFFSET_ACC]);
      y = (int16_t) ((mpu60x0_trans.buf[2+MPU_OFFSET_ACC] << 8) | 
mpu60x0_trans.buf[3+MPU_OFFSET_ACC]);
      z = (int16_t) ((mpu60x0_trans.buf[4+MPU_OFFSET_ACC] << 8) | 
mpu60x0_trans.buf[5+MPU_OFFSET_ACC]);
VECT3_ASSIGN(imu.accel_unscaled, x, -y, -z);

#define MPU_OFFSET_GYRO 9
      x = (int16_t) ((mpu60x0_trans.buf[0+MPU_OFFSET_GYRO] << 8) | 
mpu60x0_trans.buf[1+MPU_OFFSET_GYRO]);
      y = (int16_t) ((mpu60x0_trans.buf[2+MPU_OFFSET_GYRO] << 8) | 
mpu60x0_trans.buf[3+MPU_OFFSET_GYRO]);
      z = (int16_t) ((mpu60x0_trans.buf[4+MPU_OFFSET_GYRO] << 8) | 
mpu60x0_trans.buf[5+MPU_OFFSET_GYRO]);
      RATES_ASSIGN(imu.gyro_unscaled, x, -y, -z); // Update the IMU 
gyro values