INAV 1.7.0

This version has some significant differences from 1.6.x, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

Known bugs

• RTH descent might not work at all, be too slow or too aggressive and don't respect the landing speed on a fixed wing

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
mag_hold_rate_limit	heading_hold_rate_limit
nav_max_speed	nav_auto_speed
nav_max_climb_rate	nav_auto_climb_rate

And nav_fw_roll2pitch is removed due to no longer necessary. GPS modes for fixedwing now uses Turn Assist mode.

Servo mixer parser changed (Very important step for fixed winger)

Angle at min / max has been removed due to it was newer used.

So the servo mixer no longer have does defined, and if you try to copy paste from 1.6.1 release it will not work!

If you copy and paste old value like this you will get parse error:

# servo 3 1070 1950 1500 90 90 -80 -1

Parse error

You will need to remove 90 90 So it looks like this:
servo 3 1070 1950 1500 -80 -1

Please, verify your servo movement after updating to INAV 1.7

Airplane turn assistant

This release features new TURN ASSIST mode for airplanes. In this mode INAV will automatically do a coordinated balanced turn with ailerons, elevator and rudder. Until we have pitot airspeed sensor support this feature requires that your set cruize airspeed via fw_reference_airspeed CLI setting.

Airplane autotune

AUTOTUNE mode is a flight mode that acts on top of normal ANGLE/HORIZON/ACRO mode and uses changes in flight attitude input by the pilot to learn the tuning values for roll, pitch and yaw tuning. Please read the AUTOTUNE manual carefully before proceeding.

WARNING: You may find the plane is quite sluggish when you first enter AUTOTUNE. You will find that as the tune progresses this will get better. Make sure your flight area has plenty of room for slow large-radius turns.

Heading Hold flight mode

This flight mode replaces MAG and HEADING LOCK modes. It affects only yaw axis and can be enabled together with any other flight mode. It helps to maintain current heading without pilots input and can be used with and without magnetometer support. When yaw stick is neutral position, Heading Hold mode tries to keep heading (azimuth if compass sensor is available) at a defined direction. When pilot moves yaw stick, Heading Hold is temporary disabled and is waiting for a new setpoint.

Heading hold only uses yaw control (rudder) so it won't work on a flying wing which has no rudder.

New boards

• KROOZX board
• BEEROTORF4 board
• ANYFCF7 board

New features

• Sonar is back enabled with proper hardware detection. Not recommended to be used for flight yet.
• Support for MS5607 baro sensor
• Support for Spansion S25FL116 SPI memory chip
• Flaperon support moved to mixer code. Can be configured for custom airplane mix as separate flaps now
• Enable airplane setups for Sparky board
• Rename MAG mode to Heading Hold mode and allow to operate without compass
• Fixed-wing autotune
• Preliminary support for analog airspeed sensor. No boards support this currently.
• MAVLink made bidirectional. Limited subset of waypoints is supported via QGroundControl and similar software
• Add support for more baud rates (1200 to 921600)
• Add noreboot option to defaults CLI command. defaults noreboot will reset board to defaults but won't reboot the board to allow you to apply configuration right away.
• Remove failsafe channel fallback. Now receiver channel values are always received, but in case of signal loss - not used.
• Enable SoftSerial feature for AIRHEROF3
• HoTT telemetry refactoring
• BLHeli 4wif catch up with Betaflight
• Log last disarm reason to blackbox, report via LTM
• Improve run-time calibration to be faster and more accurate
• Initial cut on coordinated turn code for airplanes. TURN ASSIST flight mode will automatically apply rudder and elevator when commanding an aileron-only banked turn.
• Barometer glitch detection and cancellation
• Improve climb-out logic for airplanes. Use bigger margin for error if possible.
• OMNIBUSF4 target now supports tricopter setup
• Some F7 fixes and performance improvements
• Log hardware health status to blackbox

Bugs fixed

• Fix incorrect handling of beeper -ON_USB
• Fixed speed limitation by nav_max_speed enforced even in manual flying
• Fix HMC5883L detection and initialisation in presence of magnetic fields
• Fix broken MPU6500 detection and init
• Fix a bug with falling out of the sky when loosing GPS in FAILSAFE RTH. Now will use SET-THR (landing) as a backup in case RTH is aborted during failsafe.
• Make LTM send X-Frame even for targets w/o GPS
• Allow FAILSAFE to override PASSTHROUGH mode. Fix a bug with failsafe not engaging when plane is in PASSTHROUGH.
• Fix a bug with FAILSAFE locking pilot out of control when board is disarmed by timeout.
• Fix non-working IBUS receiver w/o telemetry
• Fix option to use more motor outputs than are physically available (might cause board to crash)
• Limit RC command processing rate. Fix a bug with stick combos being processed at extreme rate on some receivers
• Custom current metter scale for OmnibusF4 Pro. Fix a bug with incorrect current sensor readings.
• Avoid target clash between PPM and motor output on REVO target. Fix a bug with OneShot125 and PPM being incompatible.
• Fix a bug when airplane althold was not working w/o GPS (baro only)
• Fix incorrect units on OSD when OSD_UNIT_IMPERIAL is selected
• Fixed gyro alignment for BeeRotor F4

INAV 1.7.0-RC1

This version has some significant differences from 1.6.x, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

Known bugs

• RTH descent might be too aggressive and don't respect the landing speed on a fixed wing

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
mag_hold_rate_limit	heading_hold_rate_limit
nav_max_speed	nav_auto_speed
nav_max_climb_rate	nav_auto_climb_rate

And nav_fw_roll2pitch is removed due to no longer necessary. GPS modes for fixedwing now uses Turn Assist mode.

Servo mixer parser changed (Very important step for fixed winger)

Angle at min / max has been removed due to it was newer used.

So the servo mixer no longer have does defined, and if you try to copy paste from 1.6.1 release it will not work!

If you copy and paste old value like this you will get parse error:

# servo 3 1070 1950 1500 90 90 -80 -1

Parse error

You will need to remove 90 90 So it looks like this:
servo 3 1070 1950 1500 -80 -1

Please, verify your servo movement after updating to INAV 1.7

Airplane autotune

AUTOTUNE mode is a flight mode that acts on top of normal ANGLE/HORIZON/ACRO mode and uses changes in flight attitude input by the pilot to learn the tuning values for roll, pitch and yaw tuning. Please read the AUTOTUNE manual carefully before proceeding.

WARNING: You may find the plane is quite sluggish when you first enter AUTOTUNE. You will find that as the tune progresses this will get better. Make sure your flight area has plenty of room for slow large-radius turns.

Heading Hold flight mode

This flight mode replaces MAG and HEADING LOCK modes. It affects only yaw axis and can be enabled together with any other flight mode. It helps to maintain current heading without pilots input and can be used with and without magnetometer support. When yaw stick is neutral position, Heading Hold mode tries to keep heading (azimuth if compass sensor is available) at a defined direction. When pilot moves yaw stick, Heading Hold is temporary disabled and is waiting for a new setpoint.

Heading hold only uses yaw control (rudder) so it won't work on a flying wing which has no rudder.

New boards

• KROOZX board
• BEEROTORF4 board
• ANYFCF7 board

New features

• Sonar is back enabled with proper hardware detection. Not recommended to be used for flight yet.
• Support for MS5607 baro sensor
• Support for Spansion S25FL116 SPI memory chip
• Flaperon support moved to mixer code. Can be configured for custom airplane mix as separate flaps now
• Enable airplane setups for Sparky board
• Rename MAG mode to Heading Hold mode and allow to operate without compass
• Fixed-wing autotune
• Preliminary support for analog airspeed sensor. No boards support this currently.
• MAVLink made bidirectional. Limited subset of waypoints is supported via QGroundControl and similar software
• Add support for more baud rates (1200 to 921600)
• Add noreboot option to defaults CLI command. defaults noreboot will reset board to defaults but won't reboot the board to allow you to apply configuration right away.
• Remove failsafe channel fallback. Now receiver channel values are always received, but in case of signal loss - not used.
• Enable SoftSerial feature for AIRHEROF3
• HoTT telemetry refactoring
• BLHeli 4wif catch up with Betaflight
• Log last disarm reason to blackbox, report via LTM
• Improve run-time calibration to be faster and more accurate
• Initial cut on coordinated turn code for airplanes. TURN ASSIST flight mode will automatically apply rudder and elevator when commanding an aileron-only banked turn.

Bugs fixed

• Fix incorrect handling of beeper -ON_USB
• Fixed speed limitation by nav_max_speed enforced even in manual flying
• Fix HMC5883L detection and initialisation in presence of magnetic fields
• Fix broken MPU6500 detection and init
• Fix a bug with falling out of the sky when loosing GPS in FAILSAFE RTH. Now will use SET-THR (landing) as a backup in case RTH is aborted during failsafe.
• Make LTM send X-Frame even for targets w/o GPS
• Allow FAILSAFE to override PASSTHROUGH mode. Fix a bug with failsafe not engaging when plane is in PASSTHROUGH.
• Fix a bug with FAILSAFE locking pilot out of control when board is disarmed by timeout.
• Fix non-working IBUS receiver w/o telemetry
• Fix option to use more motor outputs than are physically available (might cause board to crash)
• Limit RC command processing rate. Fix a bug with stick combos being processed at extreme rate on some receivers
• Custom current metter scale for OmnibusF4 Pro. Fix a bug with incorrect current sensor readings.
• Avoid target clash between PPM and motor output on REVO target. Fix a bug with OneShot125 and PPM being incompatible.
• Fix a bug when airplane althold was not working w/o GPS (baro only)

INAV 1.6.1

This is the bugfix release for INAV 1.6. Please have a read on release notes for version 1.6.

Known bugs

• Failsafe Stage 2 doesn't show as enabled in Configurator (it is always enabled, it's only UI bug)

New features

• Faster and more accurate baro calibration

Bugs fixed

• Airplane launch mode failure
• Multiple fixes to documentation

INAV 1.6

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

Known bugs

• Fixed wing launch mode may fail
• Failsafe Stage 2 doesn't show as enabled in Configurator (it is always enabled, it's only UI bug)

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_ff_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_ff_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_ff_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

Non-volatile storage for waypoint missions

As requested a lot - you now have possibility to create and upload a waypoint mission at home, go to the field, plug in the battery and fly the mission without the need to re-upload it.

Until GCS support is done you have two stick combos to do this:

Function	Throttle	Yaw	Pitch	Roll
Save current waypoint mission	LOW	CENTER	HIGH	LOW
Load current waypoint mission	LOW	CENTER	HIGH	HIGH

Mission is saved in Configuration memory and only one mission at a time can be saved. Feature is only available on F3+ targets due to lack of space on F1.

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss. Enabled by default so in case of failsafe your craft will continue to execute failsafe procedure until you move the sticks.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode. See this article about how it is different from PID and why it is better for airplanes.

If you want direct migration from INAV 1.5 to 1.6 without using the new FF part of the controller you need to do:
Keep P-Gain as it was
Divide I-Gain by 3.5
Zero out D-Gain / FF-gain. ( So you will loose the D-gain, but this was never recommended to use. )

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New navigation-specific OSD indications

Now board with build-in OSD (Omnibus FC) will have indications that make it suitable for navigation:

• GPS coordinates
• Home distance and direction
• Current heading
• Climb rate (vario)

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 PRO target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI
• Blackbox logging at rates dow...

INAV 1.6-RC2

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_ff_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_ff_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_ff_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

Non-volatile storage for waypoint missions

As requested a lot - you now have possibility to create and upload a waypoint mission at home, go to the field, plug in the battery and fly the mission without the need to re-upload it.

Until GCS support is done you have two stick combos to do this:

Function	Throttle	Yaw	Pitch	Roll
Save current waypoint mission	LOW	CENTER	HIGH	LOW
Load current waypoint mission	LOW	CENTER	HIGH	HIGH

Mission is saved in Configuration memory and only one mission at a time can be saved. Feature is only available on F3+ targets due to lack of space on F1.

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss. Enabled by default so in case of failsafe your craft will continue to execute failsafe procedure until you move the sticks.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode. See this article about how it is different from PID and why it is better for airplanes.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New navigation-specific OSD indications

Now board with build-in OSD (Omnibus FC) will have indications that make it suitable for navigation:

• GPS coordinates
• Home distance and direction
• Current heading
• Climb rate (vario)

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 PRO target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI
• Blackbox logging at rates down to 1/255 is now possible for logging long flights to onboard memory

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking out one extra satellite when signalling GPS fix
• 3d_deadband_throttle setting was handled incorrectly by MSP which caused corruption
• iBUS telemetry not...

INAV 1.6-RC1

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_ff_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_ff_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_ff_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

Non-volatile storage for waypoint missions

As requested a lot - you now have possibility to create and upload a waypoint mission at home, go to the field, plug in the battery and fly the mission without the need to re-upload it.

This function is available in the mwp CGS, otherwise you have two stick combos to do this:

Function	Throttle	Yaw	Pitch	Roll
Save current waypoint mission	LOW	CENTER	HIGH	LOW
Load current waypoint mission	LOW	CENTER	HIGH	HIGH

Mission is saved in Configuration memory and only one mission at a time can be saved. Feature is only available on F3+ targets due to lack of space on F1.

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss. Enabled by default so in case of failsafe your craft will continue to execute failsafe procedure until you move the sticks.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode. See this article about how it is different from PID and why it is better for airplanes.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 PRO target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI
• Blackbox logging at rates down to 1/255 is now possible for logging long flights to onboard memory
• More indications on OSD for supported targets - GPS coordinates, distance and direction to home
• 'pseudo' RSSI for Spektrum satellites (from fade count, as Betaflight)
• Profiles in the CLI are now numbered 1-3 for compatibility with the configurator; be aware if restoring settings from CLI dump.

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking...

INAV 1.6-ALPHA2

This is an ALPHA release. Use caution!

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_d_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_d_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_d_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 SD target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking out one extra satellite when signalling GPS fix
• 3d_deadband_throttle setting was handled incorrectly by MSP which caused corruption
• iBUS telemetry not functional bug
• Temporary fix for a Sparky 2 compass bug

INAV 1.6-ALPHA1

This is an ALPHA release. Use caution!

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_d_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_d_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_d_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 SD target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking out one extra satellite when signalling GPS fix
• 3d_deadband_throttle setting was handled incorrectly by MSP which caused corruption
• iBUS telemetry not functional bug

INAV 1.5.1

This is a release to fix some serious bugs in INAV-1.5 that were discovered too late to make it into that release.

As usual, you are encouraged to upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

Bugfixes

• Fix a buffer overflow in I2C driver (affecting only COLIBRI/QUANTON target)
• Fix a bug with failsafe_recovery_timeout being reset to arbitrary value
• Fix corrupt blackbox logs and hickups in MSP on F1/F4 targets
• CC3D target M3 disabled bug

Happy flying!

INAV 1.5

This version has some significant differences from 1.4, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and Ledge team.

Sensor hardware configuration is now mandatory

For better robustness sensor autodetection is no longer done each boot. Instead user should explicitly configure sensor hardware on Configuration tab. User still may chose AUTO, on first boot firmware will perform autodetection and switch to first detected sensor (if any).

Hardware failure detection & arming prevention

INAV now tests if all configured sensors are available and won't allow you to arm if any of the following is true:

• CPU is overloaded
• UAV not level (aka small_angle)
• Run-time sensor calibration is not finished (covers GYRO and BARO)
• One of the sensors is configured, but not detected or not working properly
• Compass sensor is present, but not calibrated
• Accelerometer is present, but not calibrated
• Navigation is unsafe (no GPS lock, aka nav_extra_arming_safety)

Hardware failure is indicated by LED_STRIP (blue/black pattern) or beeper (fast beeps).

OSD support

Targets with onboard OSD now work properly. This is a direct port of Betaflight code and not all of the required information is displayed yet (i.e. no GPS coordinates), but that's a work in progress.

Target/feature support

• New target - QUANTON/COLIBRI
• CC3D_OPBL is no longer supported due to memory limitation

More new features and improvements

• Used tightly-coupled memory on CPUs that support it (it's an area of memory that is faster than common RAM, it also frees up common RAM for other tasks)
• New target - COLIBRI/QUANTON
• Fix missing consumed mAh reporting in LTM telemetry
• Completely new I2C driver stack - more robust, less prone to errors
• Option to specify time of good RC link for switching out from Stage 2 failsafe
• It's now possible to specify if RTH should fly home right away or reach the safe altitude first (see nav_rth_climb_first CLI parameter)
• Launching a flying wing by throwing it by the wing-tip (known as swing-launch in INAV) is now correctly detected by launch assistant
• CLI now uses sensor names instead of numbers for acc_hardware, mag_hardware etc
• Servo autotrim feature for airplanes - ability to calculate and record servo neutral position when flying in stabilised modes
• SoftSerial is now supported on AIRBOTF4 target
• Moved PPM input to pin 3 of RC connector on AIRHEROF3 target to keep compatibilty with Betaflight and earler setups

Bugfixes

• Occasional non-detection of built-in SPRacingF3 EVO compass
• Initial work done to solve the time overflow occurring at 72nd minute of operation. Issue is not completely solved yet.
• Fix a bug with coarse stick resolution in ACRO mode resulting in inability to make fine corrections (known as "deadband even when deadband = 0 issue")
• Fix UART3/I2C sharing issues on some targets
• Fix non-working UART5 on targets that support it
• Baro and GPS co-existance issue is now completely solved - baro is preferred when available
• Fix bug that allowed the MSP-aware OSD or GCS to reboot the flight controller in flight
• Tricopter mix made functional on AIRBOTF4 and OMNIBUS
• Failsafe stage 1 now defaults to "hold" on throttle channel to suite INAV better
• Fix documentation for AIRHEROF3 target
• Fix bug in PWM receiver code that may cause failse failsafe triggering
• Fix a bug that caused failsafe Stage 1 "hold" values to be ignored on flight channels if Stage 2 is disabled
• Bugfix for possible arming directly into Stage 2 failsafe procedure
• Fix buffer overflow in VCP driver that may cause corrupt blackbox downloads
• Fix a bug that allowed HOME position to be altered by MSP command in flight without explicit permission from pilot
• Lots of smaller bugfixes

Known bugs

• CC3D target doesn't work

Thanks to all who participated in improving the code and put their vehicles at risk testing new features!

Happy New Year to all pilots!
Fly safe!