Minimum time of arrival delta between non-IMU observations before data is downsampled. Baro and Magnetometer data will be averaged before downsampling, other data will be point sampled resulting in loss of information

Magnetometer measurement delay relative to IMU measurements

Barometer measurement delay relative to IMU measurements

GPS measurement delay relative to IMU measurements

Optical flow measurement delay relative to IMU measurements Assumes measurement is timestamped at trailing edge of integration period

Range finder measurement delay relative to IMU measurements

Airspeed measurement delay relative to IMU measurements

Vision Position Estimator delay relative to IMU measurements

Integer bitmask controlling GPS checks

Comment: Set bits to 1 to enable checks. Checks enabled by the following bit positions 0 : Minimum required sat count set by EKF2_REQ_NSATS 1 : Minimum required GDoP set by EKF2_REQ_GDOP 2 : Maximum allowed horizontal position error set by EKF2_REQ_EPH 3 : Maximum allowed vertical position error set by EKF2_REQ_EPV 4 : Maximum allowed speed error set by EKF2_REQ_SACC 5 : Maximum allowed horizontal position rate set by EKF2_REQ_HDRIFT. This check can only be used if the vehicle is stationary during alignment. 6 : Maximum allowed vertical position rate set by EKF2_REQ_VDRIFT. This check can only be used if the vehicle is stationary during alignment. 7 : Maximum allowed horizontal speed set by EKF2_REQ_HDRIFT. This check can only be used if the vehicle is stationary during alignment. 8 : Maximum allowed vertical velocity discrepancy set by EKF2_REQ_VDRIFT

• 0: Min sat count (EKF2_REQ_NSATS)
• 1: Min GDoP (EKF2_REQ_GDOP)
• 2: Max horizontal position error (EKF2_REQ_EPH)
• 3: Max vertical position error (EKF2_REQ_EPV)
• 4: Max speed error (EKF2_REQ_SACC)
• 5: Max horizontal position rate (EKF2_REQ_HDRIFT)
• 6: Max vertical position rate (EKF2_REQ_VDRIFT)
• 7: Max horizontal speed (EKF2_REQ_HDRIFT)
• 8: Max vertical velocity discrepancy (EKF2_REQ_VDRIFT)

Required EPH to use GPS

Required EPV to use GPS

Required speed accuracy to use GPS

Required satellite count to use GPS

Required GDoP to use GPS

Maximum horizontal drift speed to use GPS

Maximum vertical drift speed to use GPS

Rate gyro noise for covariance prediction

Accelerometer noise for covariance prediction

Process noise for IMU rate gyro bias prediction

Process noise for IMU accelerometer bias prediction

Process noise for body magnetic field prediction

Process noise for earth magnetic field prediction

Process noise for wind velocity prediction

Measurement noise for gps horizontal velocity

Measurement noise for gps position

Measurement noise for non-aiding position hold

Measurement noise for barometric altitude

Measurement noise for magnetic heading fusion

Measurement noise for magnetometer 3-axis fusion

Measurement noise for airspeed fusion

Noise for synthetic sideslip fusion

Magnetic declination

Gate size for magnetic heading fusion

Gate size for magnetometer XYZ component fusion

Integer bitmask controlling handling of magnetic declination

Comment: Set bits in the following positions to enable functions. 0 : Set to true to use the declination from the geo_lookup library when the GPS position becomes available, set to false to always use the EKF2_MAG_DECL value. 1 : Set to true to save the EKF2_MAG_DECL parameter to the value returned by the EKF when the vehicle disarms. 2 : Set to true to always use the declination as an observation when 3-axis magnetometer fusion is being used.

• 0: use geo_lookup declination
• 1: save EKF2_MAG_DECL on disarm
• 2: use declination as an observation

Type of magnetometer fusion

Comment: Integer controlling the type of magnetometer fusion used - magnetic heading or 3-axis magnetometer. If set to automatic: heading fusion on-ground and 3-axis fusion in-flight

• 0: Automatic
• 1: Magnetic heading
• 2: 3-axis fusion
• 3: None

Gate size for barometric height fusion

Gate size for GPS horizontal position fusion

Gate size for GPS velocity fusion

Gate size for TAS fusion

Replay mode

Comment: A value of 1 indicates that the ekf2 module will publish replay messages for logging.

Integer bitmask controlling data fusion and aiding methods

Comment: Set bits in the following positions to enable: 0 : Set to true to use GPS data if available 1 : Set to true to use optical flow data if available 2 : Set to true to inhibit IMU bias estimation 3 : Set to true to enable vision position fusion 4 : Set to true to enable vision yaw fusion

• 0: use GPS
• 1: use optical flow
• 2: inhibit IMU bias estimation
• 3: vision position fusion
• 4: vision yaw fusion

Determines the primary source of height data used by the EKF

Comment: The range sensor option should only be used when for operation over a flat surface as the local NED origin will move up and down with ground level.

• 0: Barometric pressure
• 1: GPS
• 2: Range sensor
• 3: Vision

Measurement noise for range finder fusion

Gate size for range finder fusion

Minimum valid range for the range finder

Measurement noise for vision position observations used when the vision system does not supply error estimates

Measurement noise for vision angle observations used when the vision system does not supply error estimates

Gate size for vision estimate fusion

Minimum valid range for the vision estimate

Measurement noise for the optical flow sensor when it's reported quality metric is at the maximum

Measurement noise for the optical flow sensor

Comment: (when it's reported quality metric is at the minimum set by EKF2_OF_QMIN). The following condition must be met: EKF2_OF_N_MAXN >= EKF2_OF_N_MIN

Optical Flow data will only be used if the sensor reports a quality metric >= EKF2_OF_QMIN

Gate size for optical flow fusion

Optical Flow data will not fused if the magnitude of the flow rate > EKF2_OF_RMAX

Terrain altitude process noise - accounts for instability in vehicle height estimate

Magnitude of terrain gradient

X position of IMU in body frame

Y position of IMU in body frame

Z position of IMU in body frame

X position of GPS antenna in body frame

Y position of GPS antenna in body frame

Z position of GPS antenna in body frame

X position of range finder origin in body frame

Y position of range finder origin in body frame

Z position of range finder origin in body frame

X position of optical flow focal point in body frame

Y position of optical flow focal point in body frame

Z position of optical flow focal point in body frame

X position of VI sensor focal point in body frame

Y position of VI sensor focal point in body frame

Z position of VI sensor focal point in body frame

Airspeed fusion threshold. A value of zero will deactivate airspeed fusion. Any other positive value will determine the minimum airspeed which will still be fused

Boolean determining if synthetic sideslip measurements should fused

Comment: A value of 1 indicates that fusion is active

Time constant of the velocity output prediction and smoothing filter

Time constant of the position output prediction and smoothing filter. Controls how tightly the output track the EKF states

1-sigma IMU gyro switch-on bias

1-sigma IMU accelerometer switch-on bias

1-sigma tilt angle uncertainty after gravity vector alignment

Range sensor pitch offset

Attitude Roll Time Constant

Comment: This defines the latency between a roll step input and the achieved setpoint (inverse to a P gain). Half a second is a good start value and fits for most average systems. Smaller systems may require smaller values, but as this will wear out servos faster, the value should only be decreased as needed.

Attitude Pitch Time Constant

Comment: This defines the latency between a pitch step input and the achieved setpoint (inverse to a P gain). Half a second is a good start value and fits for most average systems. Smaller systems may require smaller values, but as this will wear out servos faster, the value should only be decreased as needed.

Pitch rate proportional gain

Comment: This defines how much the elevator input will be commanded depending on the current body angular rate error.

Pitch rate integrator gain

Comment: This gain defines how much control response will result out of a steady state error. It trims any constant error.

Maximum positive / up pitch rate

Comment: This limits the maximum pitch up angular rate the controller will output (in degrees per second). Setting a value of zero disables the limit.

Maximum negative / down pitch rate

Comment: This limits the maximum pitch down up angular rate the controller will output (in degrees per second). Setting a value of zero disables the limit.

Pitch rate integrator limit

Comment: The portion of the integrator part in the control surface deflection is limited to this value

Roll rate proportional Gain

Comment: This defines how much the aileron input will be commanded depending on the current body angular rate error.

Roll rate integrator Gain

Comment: This gain defines how much control response will result out of a steady state error. It trims any constant error.

Roll Integrator Anti-Windup

Comment: The portion of the integrator part in the control surface deflection is limited to this value.

Maximum Roll Rate

Comment: This limits the maximum roll rate the controller will output (in degrees per second). Setting a value of zero disables the limit.

Yaw rate proportional gain

Comment: This defines how much the rudder input will be commanded depending on the current body angular rate error.

Yaw rate integrator gain

Comment: This gain defines how much control response will result out of a steady state error. It trims any constant error.

Yaw rate integrator limit

Comment: The portion of the integrator part in the control surface deflection is limited to this value

Maximum Yaw Rate

Comment: This limits the maximum yaw rate the controller will output (in degrees per second). Setting a value of zero disables the limit.

Roll control to yaw control feedforward gain

Comment: This gain can be used to counteract the "adverse yaw" effect for fixed wings. When the plane enters a roll it will tend to yaw the nose out of the turn. This gain enables the use of a yaw actuator (rudder, airbrakes, ...) to counteract this effect.

Enable wheel steering controller

Wheel steering rate proportional gain

Comment: This defines how much the wheel steering input will be commanded depending on the current body angular rate error.

Wheel steering rate integrator gain

Comment: This gain defines how much control response will result out of a steady state error. It trims any constant error.

Wheel steering rate integrator limit

Comment: The portion of the integrator part in the control surface deflection is limited to this value

Maximum wheel steering rate

Comment: This limits the maximum wheel steering rate the controller will output (in degrees per second). Setting a value of zero disables the limit.

Roll rate feed forward

Comment: Direct feed forward from rate setpoint to control surface output. Use this to obtain a tigher response of the controller without introducing noise amplification.

Pitch rate feed forward

Comment: Direct feed forward from rate setpoint to control surface output

Yaw rate feed forward

Comment: Direct feed forward from rate setpoint to control surface output

Wheel steering rate feed forward

Comment: Direct feed forward from rate setpoint to control surface output

Minimal speed for yaw coordination

Comment: For airspeeds above this value, the yaw rate is calculated for a coordinated turn. Set to a very high value to disable.

Method used for yaw coordination

Comment: The param value sets the method used to calculate the yaw rate 0: open-loop zero lateral acceleration based on kinematic constraints 1: closed-loop: try to reduce lateral acceleration to 0 by measuring the acceleration

• 0: open-loop
• 1: closed-loop

Roll Setpoint Offset

Comment: An airframe specific offset of the roll setpoint in degrees, the value is added to the roll setpoint and should correspond to the typical cruise speed of the airframe.

Pitch Setpoint Offset

Comment: An airframe specific offset of the pitch setpoint in degrees, the value is added to the pitch setpoint and should correspond to the typical cruise speed of the airframe.

Max Manual Roll

Comment: Max roll for manual control in attitude stabilized mode

Max Manual Pitch

Comment: Max pitch for manual control in attitude stabilized mode

Scale factor for flaps

Scale factor for flaperons

Airspeed mode

Comment: The param value sets the method used to publish the control state airspeed. For small wings or VTOL without airspeed sensor this parameter can be used to enable flying without an airspeed reading

• 0: use measured airspeed
• 1: use vehicle ground velocity as airspeed
• 2: declare airspeed invalid

Manual roll scale

Comment: Scale factor applied to the desired roll actuator command in full manual mode. This parameter allows to adjust the throws of the control surfaces.

Manual pitch scale

Comment: Scale factor applied to the desired pitch actuator command in full manual mode. This parameter allows to adjust the throws of the control surfaces.

Manual yaw scale

Comment: Scale factor applied to the desired yaw actuator command in full manual mode. This parameter allows to adjust the throws of the control surfaces.

Whether to scale throttle by battery power level

Comment: This compensates for voltage drop of the battery over time by attempting to normalize performance across the operating range of the battery. The fixed wing should constantly behave as if it was fully charged with reduced max thrust at lower battery percentages. i.e. if cruise speed is at 0.5 throttle at 100% battery, it will still be 0.5 at 60% battery.

Acro body x max rate

Comment: This is the rate the controller is trying to achieve if the user applies full roll stick input in acro mode.

Acro body y max rate

Comment: This is the body y rate the controller is trying to achieve if the user applies full pitch stick input in acro mode.

Acro body z max rate

Comment: This is the body z rate the controller is trying to achieve if the user applies full yaw stick input in acro mode.

Threshold for Rattitude mode

Comment: Manual input needed in order to override attitude control rate setpoints and instead pass manual stick inputs as rate setpoints

L1 period

Comment: This is the L1 distance and defines the tracking point ahead of the aircraft its following. A value of 18-25 meters works for most aircraft. Shorten slowly during tuning until response is sharp without oscillation.

L1 damping

Comment: Damping factor for L1 control.

Cruise throttle

Comment: This is the throttle setting required to achieve the desired cruise speed. Most airframes have a value of 0.5-0.7.

Throttle max slew rate

Comment: Maximum slew rate for the commanded throttle

Negative pitch limit

Comment: The minimum negative pitch the controller will output.

Positive pitch limit

Comment: The maximum positive pitch the controller will output.

Controller roll limit

Comment: The maximum roll the controller will output.

Throttle limit max

Comment: This is the maximum throttle % that can be used by the controller. For overpowered aircraft, this should be reduced to a value that provides sufficient thrust to climb at the maximum pitch angle PTCH_MAX.

Throttle limit min

Comment: This is the minimum throttle % that can be used by the controller. For electric aircraft this will normally be set to zero, but can be set to a small non-zero value if a folding prop is fitted to prevent the prop from folding and unfolding repeatedly in-flight or to provide some aerodynamic drag from a turning prop to improve the descent rate. For aircraft with internal combustion engine this parameter should be set for desired idle rpm.

Idle throttle

Comment: This is the minimum throttle while on the ground For aircraft with internal combustion engine this parameter should be set above desired idle rpm.

Throttle limit value before flare

Comment: This throttle value will be set as throttle limit at FW_LND_TLALT, before aircraft will flare.

Climbout Altitude difference

Comment: If the altitude error exceeds this parameter, the system will climb out with maximum throttle and minimum airspeed until it is closer than this distance to the desired altitude. Mostly used for takeoff waypoints / modes. Set to 0 to disable climbout mode (not recommended).

Landing slope angle

Landing flare altitude (relative to landing altitude)

Landing throttle limit altitude (relative landing altitude)

Comment: Default of -1.0 lets the system default to applying throttle limiting at 2/3 of the flare altitude.

Landing heading hold horizontal distance

Use terrain estimate during landing

Flare, minimum pitch

Comment: Minimum pitch during flare, a positive sign means nose up Applied once FW_LND_TLALT is reached

Flare, maximum pitch

Comment: Maximum pitch during flare, a positive sign means nose up Applied once FW_LND_TLALT is reached

Min. airspeed scaling factor for landing

Comment: Multiplying this factor with the minimum airspeed of the plane gives the target airspeed the landing approach. FW_AIRSPD_MIN * FW_LND_AIRSPD_SC