Stops vertical velocity bias errors preventing the vehicle from landing.
Use of the vertical derivative is blended in so that for zero vertical velocity set point, the local_position.vz is used and when the magnitude of the vertical velocity setpoint exceeds the landing speed, the local_position.z_deriv is used.
When the EKF is not fusing in observations from the NE global reference frame, the tolerance to yaw errors is much higher. This changes will prevent false triggering of the preflight fail check when operating indoors without GPS where mag field errors can be high.
This check is performed for up to 30 seconds after takeoff or until a horizontal speed of 5 m/s has been achieved.
If the vehicle is not landed and the check is active, then the yaw will be declared as failed if the velocity innovations fail for a continuous period of 1 second.
This will cause the local and global position and velocity validity to be latched false to prevent unsafe use of position control modes.
Fix the bug allowing arming without GPS checks passed in the first 20 seconds after gaining GPS lock when COM_ARM_WO_GPS is set to 0
Allow 10 seconds after boot for EKF quality checks to pass before reporting failure to allow EKF to stabilise.
Move GPS quality checking and reporting to after all innovation and bias checks.
Make messages more informative.
Add missing GPS speed accuracy check.
The commander checks use instantaneous values which are vulnerable to false negatives or positives with noisy data or transient faults.
This patch checks the estimators published pre flight check status which is based on persistent checks using filtered data.
Separate the vertical and horizontal checks for use by local position validity reporting
Add checking of yaw using a decaying envelope filter to the horizontal checks.
Publish the check result to estimator_status topic.
Change units of parameters from uSec to sec.
Change recommended FW value for COM_POS_FS_GAIN from 2 to 0
Fix error in parameter description for COM_POS_FS_PROB
Fix error in unit for COM_POS_FS_GAIN
This is required because the hardcoded values were too sensitive for fixed wing use and bad initial mag heading could trigger the failsafe and lead to crashes on launch. The defaults have been left unchanged. Suitable values for fixed wing use will need to be implemented in the airframe specific config file.
This enables control loops that are sensitive to vertical velocity offsets to use a vertical velocity that is kinematically consistent with the vertical position.
Adds parameters so that the motion checks used to switch between magnetic yaw and 3-axis fusion can be adjusted.
Modifies the check used to determine if learned mag biases can be saved. A cumulated calibration time is used rather than continuous calibration time to allow for for switching in and out of 3-axis fusion mode that is required to do calibration.
Filters the vertical position and 3-axis velocity innovations and sets the local and global position as invalid if they exceed limits during ARMING_STATE_STANDBY.
Initialisation changes to address valgrind errors
Change to default GPS and Airspeed time delay (these are overwritten by ekf2_main parameter settings)
Increase sensitivity of bad accelerometer checks
Squashed commits:
[290660d] voted_sensors_update: revert the new_accel_data check (and others)
The check removed the ability to detect sensor timeouts.
[c8dc7ad] sensors: publish changes to sensor selection
[dd90dec] sensors: ensure all sensor selections published first time
Move into functions.
Reset probation time and recalculate checks if a mode change is demanded to give the operator ability to regain control as soon as possible after nav performance is regained. (+11 squashed commits)
Squashed commits:
[a4bb800] commander: enable pilot to quickly recover from loss of position accuracy
[19e16a0] commander: rework postal probation time
[f96284e] commander: rework bad pos and vel test probation time
[00d5f0c] commander: Allow EKF preflight checks to pass with moving vehicle
Separates the 'is using GPS' and the GPS quality checks.
Uses a reasonable subset of the GPS quality checks which allows checks to pass if the vehicle is moving.
[4cdfb5c] commander: remove unused variable
[349385a] commander: add EKF GPS quality checks to pre-arm checking
Only perform check if GPs checking is activated by parameter setting.
Display fault messages that makes it clear if EKF quality checks are failing or the EKF is not using GPS for another reason. We do not want to confuse this with GPS lock.
[340ae29] commander: make position invalid fail-safe more sticky
Require check to pass for 7 seconds before exiting failsafe. This is required because if GPs is failing innovation tests for a prolonged period, the EKF will periodically reset to the GPS and report good accuracy at the time of reset.
Adding this delay gives time for an underlying error condition (eg bad IMU or compass) to be re-detected.
[b04ac95] commander: Increase RAM allocation to eliminate low stack warnings
[9dca12f] commander: add missing position invalid fail-safe responses
[69f264d] commander: Update position invalid fail-safe responses
Replace separate logic for each case with a generic function
Add velocity checks.
[8e8cef1] commander: rework position validity checks
Consolidate existing checks for global and local position validity and add checking of velocity accuracy.
Enable checks to be bypassed using the CBRK_VELPOSERR parameter.
Add assessment of IMU bias and mag field estimation
Reduce warning false positives by adjusting thresholds and eliminating use of peak value plots for output observer monitoring
Clear each figure after saving to reduce memory usage
Miscellaneous bug fixes and improvements including:
More conservative reporting of velocity and position accuracy when aiding is lost
Separate reporting of accuracy for local and global position
Detection and recovery from badly conditioned accel bias states and covariance values
Logic to prevent high manoeuvre levels causing bad acceleration bias learning
Reduce sensitivity of covariance prediction to timing jitter
Continue reporting of GPS quality until the later of airborne or checks pass
Add ability to perform wind estimation for multi-rotors using a specific force drag model
Paul Riseborough