- set local home using global pos and global home
- set local home using GNSS pos and global home
- set global home using global ref of local frame and local home
This is to make clear that the relevant part of the home position
message for navigator is the global one. Local home position isn't
required as everything is done in global coordinates.
The specific home_alt_valid is used when lat/lon are not used
- always try to set local or global home position when possible
- set global home with GNSS position if global pos from EKF isn't
available
- reset home when significantly moved from home before takeoff (checking
lpos or gpos or GNSS)
- reset home on takeoff transition
- reset home on mavlink arm command
- remove "home required accuracy" parameters, rely on validity flags
- fixes the deadlock in px4io ioctl mixer reset
- px4io Run() locks (CDev semaphore)
- mixer load goes through px4io ioctl MIXERIOCRESET which calls MixingOutput::resetMixerThreadSafe()
- MixingOutput::resetMixerThreadSafe() stores a Command::Type::resetMixer command in an atomic variable, schedules a work queue cycle, then sleep spins until the command is cleared
- the execution of the cycle eventually calls back into PX4IO::updateOutputs(), which tries to lock (and waits forever)
- most px4_io-v2 boards have a blue LED that breathes for status
- the pixhawk 2.1 (hex) re-used this blue LED for as an IMU heater (active low), but kept the same board id (so we have to detect at runtime)
- the new cubepilot boards (yellow, orange) inverted the polarity of this heater pin
- untangle the mess slightly so that things we know statically (eg cubepilot cubeorange LEDs and heater polarity) are handled at build time.
To pass from invalid to valid:
- time hysteresis
- some vertical velocity
- test ratio < 1
- low-passed signed test ratio < 1
To pass from valid to invalid:
- low-passed signed test ratio >= 1
At each new valid range measurement, the time derivative of the distance
to the ground is computed and compared with the estimated velocity.
The average of a normalized innovation squared statistic check is used
to detect a bias in the derivative of distance measurement,
indicating that the distance measurements are kinematically inconsistent
with the filter.
