# APX4 3.2.10 {% hint style="info" %} Please use Auterion Mission Control 1.34 or newer with this version of APX4. {% endhint %} {% hint style="info" %} Changes compared to APX4 3.2.1 {% endhint %} ### General Improvements * Boards: Disarm the PWM ESCs after reboot/hardfault/assertion, by pulling the PWM PINs low for 100ms. Fixes: depending on how fast the system reboots, a valid PWM pulse can be created which can cause the motors to spin. * v6s: add `MODULES_SIMULATION_SIMULATOR_SIH` to default build. Fixes: SIH (simulation in hardware) not enabled on Skynode S. * Commander: Only set the `force_failsafe` (not `lockdown`) flag when in flight termination. Fixes: parachute trigger not working because no actuator output allowed in `lockdown`. * Commander: Handle mode change rejection the same for mode change coming in through RC and MAVLink. Fixes: mode switch to infeasible Position mode not rejected when triggered by RC button, and instead vehicle fail-safes to Altitude mode. * Commander: Do not allow flight mode to switch to an infeasible mode after a fail-safe event. Fixes: system switching to infeasible mode and instantly fail-safes when mode change requested after another fail-safe event. * Dataman: Disabled the persistent dataman storage on Skynode S as it does not have enough storage (has no SD card). Fixes: Skynode not booting anymore when `SYS_DM_BACKEND` is set to `default (SD card)` on Skynode S. * Commander: Separate state tracking for battery\_unhealthy fail-safe. Fixes: error `duplicate check for caller_id 74`. * Mission: Replay change speed mission items on resume immediately if not going to previous waypoint. Fixes: wrong survey flight speed if operator stopped and resumed mission before reaching the survey. * UXRCE\_DDS: Add options to specify additional robustness measurements (`UXRCE_DDS_TX_TO`, `UXRCE_DDS_RX_TO`), disabled by default. Fixes: In certain situations the DDS Agent stops sending payload to the DDS client. As the DDS client though still can ping the agent the existing robustness measurements did not trigger a reconnect. * MAVLink streaming: Make scaling of throttle field of MANUAL\_CONTROL consistent with uORB message. Fixes: Input is processed \[0, 1000] -> \[-1, 1]. Output is processed \[-1, 1] -> \[-1000, 1000], which is against MAVLink definition. * Nuttx: Fix potential null pointer access in procfs\_opendir, e.g. possible to trigger via MAVLink FTP. * ARK Jetson: Increase TELEM2 RX buffer size for DDS over serial use. Fixes: Not receiving some DDS messages sent by the Jetson on the FMU. ### Sensors / State Estimation * Sensors: Automatically disable internal magnetometer if external ones are available. Fixes: Internal magnetometers are almost always highly affected by varying magnetic fields generated by the drone due to their location inside the drone, and should thus not be used for navigation. A fallback to the internal magnetometer can lead to worse performance than not using a magnetometer at all. * GNSS driver: update GPS submodule to include F9P outpute rate fix to improve RTK accuracy. * GNSS driver: Fix GPS RTCM instance selection. Fixes: RTCM injection of data received via MAVLINK. * GNSS Dump timeout increase + GNSS overflow fix. Fixes: GNSS data timeouts with RTK setups. * Integrator: Prevent overflow of dt in integrator class. Fixes: Overflow of dt variable in Integrator class for sensors with low sampling rates. * EKF2: Fix flow derivation for negative HAGL. Fixes: Drone climbs again shortly before touching down when landing with optical flow. * ADS1115 driver: Rework to address stability problems. Fixes: Spamming of console, probing/sensor detection and internal I2C error handling. * Magnetometer calibration: Fix large vehicle magnetometer calibration. Fixes: The heading after a quick magnetometer calibration ("large vehicle mag calibration") is sometimes off by up to 10-15 degrees, but correct after a reboot. * EKF2: improve optical flow stability near the ground. Fixes: Some EKF stability issues were occurring near the ground, where the optical flow measurement is near its singularity point (0 distance). * GPS: Parse RTCM3 and NAV in parallel. Fixes: The NAV + RTCM3 parser can block each other and can cause significant delay until the parser gets in sync again. ### Copter / VTOL (Hover) * Flight Task Manual: Reset `dist_to_ground_lock` if `dist_to_bottom` is not valid. Fixes: Vehicle can climb unexpectedly back to previous altitude setpoint in manual Position mode when flying close to maximum range of distance sensor. * Multicopter attitude control: Fix yaw jump when switching from stabilized to another mode. * Multicopter position control: Improve behavior of "nudging" during landing. Fixes: Vehicle turns instead of translates in some conditions while nudging the vehicle during the landing. * VTOL: Fix attitude setpoint being overwritten in Stabilized mode transitions. Fixes: Pilot not being able to set roll/pitch setpoints manually during transition. * Multicopter: Avoid double compensation of yaw reset in Stabilized mode. Fixes: Unexpected yaw bahvior when the validity of the heading estimate changes. ### Fixed-wing / VTOL Plane (Cruise) * EKF2: Allow sideslip fusion to always start together with airspeed fusion. Fixes: Race conditions causing the wind initialization to fail during the transition to cruise flight as the EKF needs to receive the message before activating the sideslip fusion. * EKF2: Allow airspeed fusion only during front transition and cruise flight. Fixes: Airspeed fusion happening in hover mode (VTOL) when airspeed is high, resulting in toggling between Descend and RTL. * EKF2: Constrain max variance by zero innovation update. Fixes: Estimator instability caused by manual position reset after flying for a prolonged period with wind dead-reckoning. * EKF-AGP: Do not reset to AGP (Auxiliary Global Position) measurement if GNSS fusion is active. Fixes: AGP resetting the position after rejection period, even if GNSS was fused all the time. * VTOL: Reduce schedule frequency by only registering relevant callbacks. Fixes: Specific ESCs lose communication and go to failsafe state when switching from MC -> FW in case of using DSHOT150. ### New Parameters | Parameter Name | Affecting | About | | ------------------ | --------- | ---------------------------------------------------------------------------------- | | UXRCE\_DDS\_TX\_TO | All | Defines after how many seconds of not receiving RX payload the connection is reset | | UXRCE\_DDS\_RX\_TO | All | Defines after how many seconds of not sending TX payload the connection is reset | | | | |