I've added a queue depth of 4 for sensor_accel and sensor_gyro. This is initially added because it's not always possible for the `vehicle_acceleration` to keep up with every publication of the primary accelerator as it runs in the same thread as ekf2, various controllers, etc.
Later this mechanism will be used in a few areas
- rate limit `vehicle_angular_velocity` and `vehicle_acceleration` without missing any raw data
- move IMU integration to `vehicle_imu` and out of the actual driver threads, eliminating the need for sensor_accel_integrated and sensor_gyro_integrated
- integrate raw gyro synchronized with optical flow measurements
- gyro filtering (low-pass and notch) only performed on primary gyro in `sensors/vehicle_angular_velocity` instead of every gyro in `PX4Gyroscope`
- sample rate is calculated from actual updates (the fixed value was slightly wrong in many cases, and very wrong in a few)
- In the FIFO case the array is now averaged and published in `sensor_gyro` for filtering downstream. I'll update this in the future to use the full FIFO array (if available), but right now it should be fine.
- this provides some extra space when the FIFO transfers don't align perfectly
- I've also made an effort to keep the different drivers (icm20602, icm20608g, ism330ldc) in sync so we can factor out the common portions later once we've confident in the pattern.
- uses the FIFO and SPI DMA to transfer full raw data (8 kHz gyro, 4 kHz accel)
- new sensor messages for better visibility
- sensor_{accel, gyro}_fifo: full raw data for optional logging and analysis
- sensor_{accel, gyro}_status: metadata, clipping, etc
- currently not enabled by default
Daniel Agar