this moves to using a 1p filter on the high rate data, followed by
averaging down to 1kHz then a 2p filter to apply configured cutoff
frequency.
It also fixes the FIFO reset to not cause data corruption. We need to
disable all FIFO channels before doing the reset, and wait for the
FIFO to stop in the sensor.
Finally it moves sampling of the MPU6000 and MPU9250 into the main
thread. That significantly improves scheduling performance as we no
longer get long FIFO SPI transfers happening during other tasks. All
transfers happen at the start of the fast loop. That makes timing much
more predictable.
Thanks to Leonard and Paul for help with this design!
this allows enable/disable of fast sampling per IMU, making
experimentation easier.
It also fixes the fast sampling to always average over 8 samples, and
fixes the 9250 to use the correct accumulator when not doing fast
sampling
Two cases of what seems to be FIFO alignment errors have been seen on
a Pixracer-beta board with a ICM-20608. At a cost of 2 extra bytes per
transfer we can catch these by looking for sudden temperature changes
caused by bad data in the temperature registers.
Due to the way the headers are organized changing a single change in an
inertial sensor driver would trigger a rebuild for most of the files in
the project. Time could be saved by using ccache (since most of the
things didn't change) but we can do better, i.e. re-organize the headers
so we don't have to re-build everything.
With this patch only AP_InertialSensor/AP_InertialSensor.h is exposed to
most users. There are some corner cases to integrate with some example
code, but most of the places now depend only on this header and this
header doesn't depend on the specific backends.
Now changing a single header, e.g. AP_InertialSensor_L3G4200D.h triggers
a rebuild only of these files:
$ waf copter
'copter' finished successfully (0.000s)
Waf: Entering directory `/home/lucas/p/dronecode/ardupilot/build/minlure'
[ 80/370] Compiling libraries/AP_InertialSensor/AP_InertialSensor.cpp
[ 84/370] Compiling libraries/AP_InertialSensor/AP_InertialSensor_L3G4200D.cpp
[310/370] Linking build/minlure/ArduCopter/libArduCopter_libs.a
[370/370] Linking build/minlure/bin/arducopter
Waf: Leaving directory `/home/lucas/p/dronecode/ardupilot/build/minlure'
Most of AP_Progmem is already gone so we can stop including it in most
of the places. The only places that need it are the ones using
pgm_read_*() APIs.
In some cases the header needed to be added in the .cpp since it was
removed from the .h to reduce scope. In those cases the headers were
also reordered.
The code with ifdef for !FAST_SAMPLING is bit rotting and the example
for AP_InertialSensor is currently broken for this case. Instead of
adding more ifdefs, remove the legacy implementation for !FAST_SAMPLING
since we don't support it anymore.
Reported by Grant:
/home/grant/3dr/ardupilot/libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp:
In member function 'void AP_InertialSensor_MPU6000::_accumulate(uint8_t*,
uint8_t)':
/home/grant/3dr/ardupilot/libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp:776:20:
error: no match for 'operator+=' (operand types are 'Vector3l {aka
Vector3<long int>}' and 'Vector3f {aka Vector3<float>}')
_accel_sum += accel;
/home/grant/3dr/ardupilot/libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp:777:19:
error: no match for 'operator+=' (operand types are 'Vector3l {aka
Vector3<long int>}' and 'Vector3f {aka Vector3<float>}')
_gyro_sum += gyro;
Read temperature as part of the normal burst. This is not very costly since it
is part of the burst read in i2c and already read in spi.
It is meant to be used for imu heating.
The filter is set to 1Hz on temperature because of the inherent inertia of
heating systems.
Instead of just doing a static cast to the desired class, use a method
named "from". Pros:
- When we have data shared on the parent class, the code is cleaner in
child class when it needs to access this data. Almost all the data
we use in AP_HAL benefits from this
- There's a minimal type checking because now we are using a method
that can only receive the type of the parent class
We were able to read only the block of registers that are part of the
data output from accelerometer/gyroscope. In order to support reading
the external sensors we need support for reading a generic block of
registers.
This commit changes the way libraries headers are included in source files:
- If the header is in the same directory the source belongs to, so the
notation '#include ""' is used with the path relative to the directory
containing the source.
- If the header is outside the directory containing the source, then we use
the notation '#include <>' with the path relative to libraries folder.
Some of the advantages of such approach:
- Only one search path for libraries headers.
- OSs like Windows may have a better lookup time.
We were previously leaking the AP_MPU6000_BusDriver if the
~AP_InertialSensor_MPU6000::detect*() failed. In order to avoid the
leak move the repeated code in a single private _detect() member that
receives everything as argument. Then this method takes ownership of the
objects.
By a adding a destructor to AP_InertialSensor_MPU6000 it becomes easier to
free the objects it takes ownership of.
The methods actually use the enum from AP_HAL::SPIDeviceDriver, so don't
declare a new one. The I2C implementation is empty; if we actually start
to use it we'd better move the bus abstraction to HAL.
Lucas De Marchi
Andrew Tridgell
hiro2233
Mathieu OTHACEHE
Gustavo Jose de Sousa
Aaron Wang Shi
José Roberto de Souza
Julien BERAUD