1561 lines
83 KiB
C++
1561 lines
83 KiB
C++
/*
|
|
24 state EKF based on the derivation in https://github.com/PX4/ecl/
|
|
blob/master/matlab/scripts/Inertial%20Nav%20EKF/GenerateNavFilterEquations.m
|
|
|
|
Converted from Matlab to C++ by Paul Riseborough
|
|
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
#pragma once
|
|
|
|
|
|
#if !defined(HAL_DEBUG_BUILD) || !HAL_DEBUG_BUILD
|
|
#pragma GCC optimize("O2")
|
|
#endif
|
|
|
|
#include "AP_NavEKF3_feature.h"
|
|
#include <AP_Common/Location.h>
|
|
#include <AP_Math/AP_Math.h>
|
|
#include <AP_Math/vectorN.h>
|
|
#include <AP_NavEKF/AP_NavEKF_core_common.h>
|
|
#include <AP_NavEKF/AP_NavEKF_Source.h>
|
|
#include <AP_NavEKF/EKF_Buffer.h>
|
|
#include <AP_InertialSensor/AP_InertialSensor.h>
|
|
#include <AP_DAL/AP_DAL.h>
|
|
|
|
#include "AP_NavEKF/EKFGSF_yaw.h"
|
|
|
|
// GPS pre-flight check bit locations
|
|
#define MASK_GPS_NSATS (1<<0)
|
|
#define MASK_GPS_HDOP (1<<1)
|
|
#define MASK_GPS_SPD_ERR (1<<2)
|
|
#define MASK_GPS_POS_ERR (1<<3)
|
|
#define MASK_GPS_YAW_ERR (1<<4)
|
|
#define MASK_GPS_POS_DRIFT (1<<5)
|
|
#define MASK_GPS_VERT_SPD (1<<6)
|
|
#define MASK_GPS_HORIZ_SPD (1<<7)
|
|
|
|
#define earthRate 0.000072921f // earth rotation rate (rad/sec)
|
|
|
|
// maximum allowed gyro bias (rad/sec)
|
|
#define GYRO_BIAS_LIMIT 0.5f
|
|
|
|
// initial accel bias uncertainty as a fraction of the state limit
|
|
#define ACCEL_BIAS_LIM_SCALER 0.2f
|
|
|
|
// target update time for the EKF in msec and sec
|
|
#define EKF_TARGET_DT_MS 12
|
|
#define EKF_TARGET_DT 0.012f
|
|
|
|
// mag fusion final reset altitude (using NED frame so altitude is negative)
|
|
#define EKF3_MAG_FINAL_RESET_ALT 2.5f
|
|
|
|
// learning rate for mag biases when using GPS yaw
|
|
#define EK3_GPS_MAG_LEARN_RATE 0.005f
|
|
|
|
// learning limit for mag biases when using GPS yaw (Gauss)
|
|
#define EK3_GPS_MAG_LEARN_LIMIT 0.02f
|
|
|
|
// maximum number of yaw resets due to detected magnetic anomaly allowed per flight
|
|
#define MAG_ANOMALY_RESET_MAX 2
|
|
|
|
// number of seconds a request to reset the yaw to the GSF estimate is active before it times out
|
|
#define YAW_RESET_TO_GSF_TIMEOUT_MS 5000
|
|
|
|
// accuracy threshold applied to GSF yaw estimate use
|
|
#define GSF_YAW_ACCURACY_THRESHOLD_DEG 15.0f
|
|
|
|
// number of continuous valid GSF yaw estimates required to confirm valid hostory
|
|
#define GSF_YAW_VALID_HISTORY_THRESHOLD 5
|
|
|
|
// minimum variances allowed for velocity and position states
|
|
#define VEL_STATE_MIN_VARIANCE 1E-4
|
|
#define POS_STATE_MIN_VARIANCE 1E-4
|
|
|
|
// maximum number of times the vertical velocity variance can hit the lower limit before the
|
|
// associated states, variances and covariances are reset
|
|
#define EKF_TARGET_RATE_HZ uint32_t(1.0 / EKF_TARGET_DT)
|
|
#define VERT_VEL_VAR_CLIP_COUNT_LIM (5 * EKF_TARGET_RATE_HZ)
|
|
|
|
// limit on horizontal position states
|
|
#if HAL_WITH_EKF_DOUBLE
|
|
#define EK3_POSXY_STATE_LIMIT 50.0e6
|
|
#else
|
|
#define EK3_POSXY_STATE_LIMIT 1.0e6
|
|
#endif
|
|
|
|
// IMU acceleration process noise in m/s/s used when bad vibration affected IMU accel is detected
|
|
#define BAD_IMU_DATA_ACC_P_NSE 5.0f
|
|
|
|
// Number of milliseconds of bad IMU data before a reset to vertical position and velocity height sources is performed
|
|
#define BAD_IMU_DATA_TIMEOUT_MS 1000
|
|
|
|
// number of milliseconds the bad IMU data response settings will be held after the last bad IMU data is detected
|
|
#define BAD_IMU_DATA_HOLD_MS 10000
|
|
|
|
// wind state variance limits
|
|
#define WIND_VEL_VARIANCE_MAX 400.0f
|
|
#define WIND_VEL_VARIANCE_MIN 0.25f
|
|
|
|
|
|
class NavEKF3_core : public NavEKF_core_common
|
|
{
|
|
public:
|
|
// Constructor
|
|
NavEKF3_core(class NavEKF3 *_frontend);
|
|
|
|
// setup this core backend
|
|
bool setup_core(uint8_t _imu_index, uint8_t _core_index);
|
|
|
|
// Initialise the states from accelerometer and magnetometer data (if present)
|
|
// This method can only be used when the vehicle is static
|
|
bool InitialiseFilterBootstrap(void);
|
|
|
|
// Update Filter States - this should be called whenever new IMU data is available
|
|
// The predict flag is set true when a new prediction cycle can be started
|
|
void UpdateFilter(bool predict);
|
|
|
|
// Check basic filter health metrics and return a consolidated health status
|
|
bool healthy(void) const;
|
|
|
|
// Return a consolidated error score where higher numbers are less healthy
|
|
// Intended to be used by the front-end to determine which is the primary EKF
|
|
float errorScore(void) const;
|
|
|
|
// Write the last calculated NE position relative to the reference point (m).
|
|
// If a calculated solution is not available, use the best available data and return false
|
|
// If false returned, do not use for flight control
|
|
bool getPosNE(Vector2f &posNE) const;
|
|
|
|
// Write the last calculated D position relative to the reference point (m).
|
|
// If a calculated solution is not available, use the best available data and return false
|
|
// If false returned, do not use for flight control
|
|
bool getPosD(float &posD) const;
|
|
|
|
// return NED velocity in m/s
|
|
void getVelNED(Vector3f &vel) const;
|
|
|
|
// return estimate of true airspeed vector in body frame in m/s
|
|
// returns false if estimate is unavailable
|
|
bool getAirSpdVec(Vector3f &vel) const;
|
|
|
|
// return the innovation in m/s, innovation variance in (m/s)^2 and age in msec of the last TAS measurement processed
|
|
// returns false if the data is unavailable
|
|
bool getAirSpdHealthData(float &innovation, float &innovationVariance, uint32_t &age_ms) const;
|
|
|
|
// Return the rate of change of vertical position in the down direction (dPosD/dt) in m/s
|
|
// This can be different to the z component of the EKF velocity state because it will fluctuate with height errors and corrections in the EKF
|
|
// but will always be kinematically consistent with the z component of the EKF position state
|
|
float getPosDownDerivative(void) const;
|
|
|
|
// return body axis gyro bias estimates in rad/sec
|
|
void getGyroBias(Vector3f &gyroBias) const;
|
|
|
|
// return accelerometer bias in m/s/s
|
|
void getAccelBias(Vector3f &accelBias) const;
|
|
|
|
// reset body axis gyro bias estimates
|
|
void resetGyroBias(void);
|
|
|
|
// Resets the baro so that it reads zero at the current height
|
|
// Resets the EKF height to zero
|
|
// Adjusts the EKF origin height so that the EKF height + origin height is the same as before
|
|
// Returns true if the height datum reset has been performed
|
|
// If using a range finder for height no reset is performed and it returns false
|
|
bool resetHeightDatum(void);
|
|
|
|
// return the horizontal speed limit in m/s set by optical flow sensor limits
|
|
// return the scale factor to be applied to navigation velocity gains to compensate for increase in velocity noise with height when using optical flow
|
|
void getEkfControlLimits(float &ekfGndSpdLimit, float &ekfNavVelGainScaler) const;
|
|
|
|
// return the NED wind speed estimates in m/s (positive is air moving in the direction of the axis)
|
|
// returns true if wind state estimation is active
|
|
bool getWind(Vector3f &wind) const;
|
|
|
|
// return earth magnetic field estimates in measurement units / 1000
|
|
void getMagNED(Vector3f &magNED) const;
|
|
|
|
// return body magnetic field estimates in measurement units / 1000
|
|
void getMagXYZ(Vector3f &magXYZ) const;
|
|
|
|
// return the index for the active sensors
|
|
uint8_t getActiveAirspeed() const;
|
|
|
|
// Return estimated magnetometer offsets
|
|
// Return true if magnetometer offsets are valid
|
|
bool getMagOffsets(uint8_t mag_idx, Vector3f &magOffsets) const;
|
|
|
|
// Return the last calculated latitude, longitude and height in WGS-84
|
|
// If a calculated location isn't available, return a raw GPS measurement
|
|
// The status will return true if a calculation or raw measurement is available
|
|
// The getFilterStatus() function provides a more detailed description of data health and must be checked if data is to be used for flight control
|
|
bool getLLH(struct Location &loc) const;
|
|
|
|
// return the latitude and longitude and height used to set the NED origin
|
|
// All NED positions calculated by the filter are relative to this location
|
|
// Returns false if the origin has not been set
|
|
bool getOriginLLH(struct Location &loc) const;
|
|
|
|
// set the latitude and longitude and height used to set the NED origin
|
|
// All NED positions calculated by the filter will be relative to this location
|
|
// returns false if Absolute aiding and GPS is being used or if the origin is already set
|
|
bool setOriginLLH(const Location &loc);
|
|
|
|
// return estimated height above ground level
|
|
// return false if ground height is not being estimated.
|
|
bool getHAGL(float &HAGL) const;
|
|
|
|
// return the Euler roll, pitch and yaw angle in radians
|
|
void getEulerAngles(Vector3f &eulers) const;
|
|
|
|
// return the transformation matrix from XYZ (body) to NED axes
|
|
void getRotationBodyToNED(Matrix3f &mat) const;
|
|
|
|
// return the quaternions defining the rotation from NED to XYZ (body) axes
|
|
void getQuaternion(Quaternion &quat) const;
|
|
|
|
// return the innovations for the NED Pos, NED Vel, XYZ Mag and Vtas measurements
|
|
bool getInnovations(Vector3f &velInnov, Vector3f &posInnov, Vector3f &magInnov, float &tasInnov, float &yawInnov) const;
|
|
|
|
// return the synthetic air data drag and sideslip innovations
|
|
void getSynthAirDataInnovations(Vector2f &dragInnov, float &betaInnov) const;
|
|
|
|
// return the innovation consistency test ratios for the velocity, position, magnetometer and true airspeed measurements
|
|
bool getVariances(float &velVar, float &posVar, float &hgtVar, Vector3f &magVar, float &tasVar, Vector2f &offset) const;
|
|
|
|
// get a particular source's velocity innovations
|
|
// returns true on success and results are placed in innovations and variances arguments
|
|
bool getVelInnovationsAndVariancesForSource(AP_NavEKF_Source::SourceXY source, Vector3f &innovations, Vector3f &variances) const WARN_IF_UNUSED;
|
|
|
|
// should we use the compass? This is public so it can be used for
|
|
// reporting via ahrs.use_compass()
|
|
bool use_compass(void) const;
|
|
|
|
// write the raw optical flow measurements
|
|
// rawFlowQuality is a measured of quality between 0 and 255, with 255 being the best quality
|
|
// rawFlowRates are the optical flow rates in rad/sec about the X and Y sensor axes.
|
|
// rawGyroRates are the sensor rotation rates in rad/sec measured by the sensors internal gyro
|
|
// The sign convention is that a RH physical rotation of the sensor about an axis produces both a positive flow and gyro rate
|
|
// msecFlowMeas is the scheduler time in msec when the optical flow data was received from the sensor.
|
|
// posOffset is the XYZ flow sensor position in the body frame in m
|
|
void writeOptFlowMeas(const uint8_t rawFlowQuality, const Vector2f &rawFlowRates, const Vector2f &rawGyroRates, const uint32_t msecFlowMeas, const Vector3f &posOffset);
|
|
|
|
// retrieve latest corrected optical flow samples (used for calibration)
|
|
bool getOptFlowSample(uint32_t& timeStamp_ms, Vector2f& flowRate, Vector2f& bodyRate, Vector2f& losPred) const;
|
|
|
|
/*
|
|
* Write body frame linear and angular displacement measurements from a visual odometry sensor
|
|
*
|
|
* quality is a normalised confidence value from 0 to 100
|
|
* delPos is the XYZ change in linear position measured in body frame and relative to the inertial reference at time_ms (m)
|
|
* delAng is the XYZ angular rotation measured in body frame and relative to the inertial reference at time_ms (rad)
|
|
* delTime is the time interval for the measurement of delPos and delAng (sec)
|
|
* timeStamp_ms is the timestamp of the last image used to calculate delPos and delAng (msec)
|
|
* delay_ms is the average delay of external nav system measurements relative to inertial measurements
|
|
* posOffset is the XYZ body frame position of the camera focal point (m)
|
|
*/
|
|
void writeBodyFrameOdom(float quality, const Vector3f &delPos, const Vector3f &delAng, float delTime, uint32_t timeStamp_ms, uint16_t delay_ms, const Vector3f &posOffset);
|
|
|
|
/*
|
|
* Write odometry data from a wheel encoder. The axis of rotation is assumed to be parallel to the vehicle body axis
|
|
*
|
|
* delAng is the measured change in angular position from the previous measurement where a positive rotation is produced by forward motion of the vehicle (rad)
|
|
* delTime is the time interval for the measurement of delAng (sec)
|
|
* timeStamp_ms is the time when the rotation was last measured (msec)
|
|
* posOffset is the XYZ body frame position of the wheel hub (m)
|
|
* radius is the effective rolling radius of the wheel (m)
|
|
*/
|
|
void writeWheelOdom(float delAng, float delTime, uint32_t timeStamp_ms, const Vector3f &posOffset, float radius);
|
|
|
|
/*
|
|
* Return data for debugging body frame odometry fusion:
|
|
*
|
|
* velInnov are the XYZ body frame velocity innovations (m/s)
|
|
* velInnovVar are the XYZ body frame velocity innovation variances (m/s)**2
|
|
*
|
|
* Return the time stamp of the last odometry fusion update (msec)
|
|
*/
|
|
uint32_t getBodyFrameOdomDebug(Vector3f &velInnov, Vector3f &velInnovVar);
|
|
|
|
/*
|
|
* Writes the measurement from a yaw angle sensor
|
|
*
|
|
* yawAngle: Yaw angle of the vehicle relative to true north in radians where a positive angle is
|
|
* produced by a RH rotation about the Z body axis. The Yaw rotation is the first rotation in a
|
|
* 321 (ZYX) or a 312 (ZXY) rotation sequence as specified by the 'type' argument.
|
|
* yawAngleErr is the 1SD accuracy of the yaw angle measurement in radians.
|
|
* timeStamp_ms: System time in msec when the yaw measurement was taken. This time stamp must include
|
|
* all measurement lag and transmission delays.
|
|
* type: An integer specifying Euler rotation order used to define the yaw angle.
|
|
* type = 1 specifies a 312 (ZXY) rotation order, type = 2 specifies a 321 (ZYX) rotation order.
|
|
*/
|
|
void writeEulerYawAngle(float yawAngle, float yawAngleErr, uint32_t timeStamp_ms, uint8_t type);
|
|
|
|
/*
|
|
* Write position and quaternion data from an external navigation system
|
|
*
|
|
* pos : position in the RH navigation frame. Frame is assumed to be NED if frameIsNED is true. (m)
|
|
* quat : quaternion desribing the rotation from navigation frame to body frame
|
|
* posErr : 1-sigma spherical position error (m)
|
|
* angErr : 1-sigma spherical angle error (rad)
|
|
* timeStamp_ms : system time the measurement was taken, not the time it was received (mSec)
|
|
* delay_ms : average delay of external nav system measurements relative to inertial measurements
|
|
* resetTime_ms : system time of the last position reset request (mSec)
|
|
*
|
|
*/
|
|
void writeExtNavData(const Vector3f &pos, const Quaternion &quat, float posErr, float angErr, uint32_t timeStamp_ms, uint16_t delay_ms, uint32_t resetTime_ms);
|
|
|
|
/*
|
|
* Write velocity data from an external navigation system
|
|
*
|
|
* vel : velocity in NED (m)
|
|
* err : velocity error (m/s)
|
|
* timeStamp_ms : system time the measurement was taken, not the time it was received (mSec)
|
|
* delay_ms : average delay of external nav system measurements relative to inertial measurements
|
|
*/
|
|
void writeExtNavVelData(const Vector3f &vel, float err, uint32_t timeStamp_ms, uint16_t delay_ms);
|
|
|
|
// Set to true if the terrain underneath is stable enough to be used as a height reference
|
|
// in combination with a range finder. Set to false if the terrain underneath the vehicle
|
|
// cannot be used as a height reference. Use to prevent range finder operation otherwise
|
|
// enabled by the combination of EK3_RNG_USE_HGT and EK3_RNG_USE_SPD parameters.
|
|
void setTerrainHgtStable(bool val);
|
|
|
|
/*
|
|
return the filter fault status as a bitmasked integer
|
|
0 = quaternions are NaN
|
|
1 = velocities are NaN
|
|
2 = badly conditioned X magnetometer fusion
|
|
3 = badly conditioned Y magnetometer fusion
|
|
5 = badly conditioned Z magnetometer fusion
|
|
6 = badly conditioned airspeed fusion
|
|
7 = badly conditioned synthetic sideslip fusion
|
|
7 = filter is not initialised
|
|
*/
|
|
void getFilterFaults(uint16_t &faults) const;
|
|
|
|
/*
|
|
Return a filter function status that indicates:
|
|
Which outputs are valid
|
|
If the filter has detected takeoff
|
|
If the filter has activated the mode that mitigates against ground effect static pressure errors
|
|
If GPS data is being used
|
|
*/
|
|
void getFilterStatus(nav_filter_status &status) const;
|
|
|
|
// send an EKF_STATUS_REPORT message to GCS
|
|
void send_status_report(class GCS_MAVLINK &link) const;
|
|
|
|
// provides the height limit to be observed by the control loops
|
|
// returns false if no height limiting is required
|
|
// this is needed to ensure the vehicle does not fly too high when using optical flow navigation
|
|
bool getHeightControlLimit(float &height) const;
|
|
|
|
// return the amount of yaw angle change due to the last yaw angle reset in radians
|
|
// returns the time of the last yaw angle reset or 0 if no reset has ever occurred
|
|
uint32_t getLastYawResetAngle(float &yawAng) const;
|
|
|
|
// return the amount of NE position change due to the last position reset in metres
|
|
// returns the time of the last reset or 0 if no reset has ever occurred
|
|
uint32_t getLastPosNorthEastReset(Vector2f &pos) const;
|
|
|
|
// return the amount of D position change due to the last position reset in metres
|
|
// returns the time of the last reset or 0 if no reset has ever occurred
|
|
uint32_t getLastPosDownReset(float &posD) const;
|
|
|
|
// return the amount of NE velocity change due to the last velocity reset in metres/sec
|
|
// returns the time of the last reset or 0 if no reset has ever occurred
|
|
uint32_t getLastVelNorthEastReset(Vector2f &vel) const;
|
|
|
|
// report any reason for why the backend is refusing to initialise
|
|
const char *prearm_failure_reason(void) const;
|
|
|
|
// report the number of frames lapsed since the last state prediction
|
|
// this is used by other instances to level load
|
|
uint8_t getFramesSincePredict(void) const;
|
|
|
|
// get the IMU index. For now we return the gyro index, as that is most
|
|
// critical for use by other subsystems.
|
|
uint8_t getIMUIndex(void) const { return gyro_index_active; }
|
|
|
|
// values for EK3_MAG_CAL
|
|
enum class MagCal {
|
|
WHEN_FLYING = 0,
|
|
WHEN_MANOEUVRING = 1,
|
|
NEVER = 2,
|
|
AFTER_FIRST_CLIMB = 3,
|
|
ALWAYS = 4
|
|
// 5 was EXTERNAL_YAW (do not use)
|
|
// 6 was EXTERNAL_YAW_FALLBACK (do not use)
|
|
};
|
|
|
|
// are we using (aka fusing) a non-compass yaw?
|
|
bool using_noncompass_for_yaw(void) const;
|
|
|
|
// are we using (aka fusing) external nav for yaw?
|
|
bool using_extnav_for_yaw() const;
|
|
|
|
// Writes the default equivalent airspeed and 1-sigma uncertainty in m/s to be used in forward flight if a measured airspeed is required and not available.
|
|
void writeDefaultAirSpeed(float airspeed, float uncertainty);
|
|
|
|
// request a reset the yaw to the EKF-GSF value
|
|
void EKFGSF_requestYawReset();
|
|
|
|
// return true if we are tilt aligned
|
|
bool have_aligned_tilt(void) const {
|
|
return tiltAlignComplete;
|
|
}
|
|
|
|
// return true if we are yaw aligned
|
|
bool have_aligned_yaw(void) const {
|
|
return yawAlignComplete;
|
|
}
|
|
|
|
void Log_Write(uint64_t time_us);
|
|
|
|
// returns true when the state estimates are significantly degraded by vibration
|
|
bool isVibrationAffected() const { return badIMUdata; }
|
|
|
|
// get a yaw estimator instance
|
|
const EKFGSF_yaw *get_yawEstimator(void) const { return yawEstimator; }
|
|
|
|
private:
|
|
EKFGSF_yaw *yawEstimator;
|
|
AP_DAL &dal;
|
|
|
|
// Reference to the global EKF frontend for parameters
|
|
class NavEKF3 *frontend;
|
|
uint8_t imu_index; // preferred IMU index
|
|
uint8_t gyro_index_active; // active gyro index (in case preferred fails)
|
|
uint8_t accel_index_active; // active accel index (in case preferred fails)
|
|
uint8_t core_index;
|
|
uint8_t imu_buffer_length;
|
|
uint8_t obs_buffer_length;
|
|
|
|
#if MATH_CHECK_INDEXES
|
|
typedef VectorN<ftype,2> Vector2;
|
|
typedef VectorN<ftype,3> Vector3;
|
|
typedef VectorN<ftype,4> Vector4;
|
|
typedef VectorN<ftype,5> Vector5;
|
|
typedef VectorN<ftype,6> Vector6;
|
|
typedef VectorN<ftype,7> Vector7;
|
|
typedef VectorN<ftype,8> Vector8;
|
|
typedef VectorN<ftype,9> Vector9;
|
|
typedef VectorN<ftype,10> Vector10;
|
|
typedef VectorN<ftype,11> Vector11;
|
|
typedef VectorN<ftype,13> Vector13;
|
|
typedef VectorN<ftype,14> Vector14;
|
|
typedef VectorN<ftype,15> Vector15;
|
|
typedef VectorN<ftype,21> Vector21;
|
|
typedef VectorN<ftype,22> Vector22;
|
|
typedef VectorN<ftype,23> Vector23;
|
|
typedef VectorN<ftype,24> Vector24;
|
|
typedef VectorN<ftype,25> Vector25;
|
|
typedef VectorN<ftype,31> Vector31;
|
|
typedef VectorN<VectorN<ftype,3>,3> Matrix3;
|
|
typedef VectorN<VectorN<ftype,24>,24> Matrix24;
|
|
typedef VectorN<VectorN<ftype,34>,50> Matrix34_50;
|
|
typedef VectorN<uint32_t,50> Vector_u32_50;
|
|
#else
|
|
typedef ftype Vector2[2];
|
|
typedef ftype Vector3[3];
|
|
typedef ftype Vector4[4];
|
|
typedef ftype Vector5[5];
|
|
typedef ftype Vector6[6];
|
|
typedef ftype Vector7[7];
|
|
typedef ftype Vector8[8];
|
|
typedef ftype Vector9[9];
|
|
typedef ftype Vector10[10];
|
|
typedef ftype Vector11[11];
|
|
typedef ftype Vector13[13];
|
|
typedef ftype Vector14[14];
|
|
typedef ftype Vector15[15];
|
|
typedef ftype Vector21[21];
|
|
typedef ftype Vector22[22];
|
|
typedef ftype Vector23[23];
|
|
typedef ftype Vector24[24];
|
|
typedef ftype Vector25[25];
|
|
typedef ftype Matrix3[3][3];
|
|
typedef ftype Matrix24[24][24];
|
|
typedef ftype Matrix34_50[34][50];
|
|
typedef uint32_t Vector_u32_50[50];
|
|
#endif
|
|
|
|
// the states are available in two forms, either as a Vector24, or
|
|
// broken down as individual elements. Both are equivalent (same
|
|
// memory)
|
|
struct state_elements {
|
|
QuaternionF quat; // quaternion defining rotation from local NED earth frame to body frame 0..3
|
|
Vector3F velocity; // velocity of IMU in local NED earth frame (m/sec) 4..6
|
|
Vector3F position; // position of IMU in local NED earth frame (m) 7..9
|
|
Vector3F gyro_bias; // body frame delta angle IMU bias vector (rad) 10..12
|
|
Vector3F accel_bias; // body frame delta velocity IMU bias vector (m/sec) 13..15
|
|
Vector3F earth_magfield; // earth frame magnetic field vector (Gauss) 16..18
|
|
Vector3F body_magfield; // body frame magnetic field vector (Gauss) 19..21
|
|
Vector2F wind_vel; // horizontal North East wind velocity vector in local NED earth frame (m/sec) 22..23
|
|
};
|
|
|
|
union {
|
|
Vector24 statesArray;
|
|
struct state_elements stateStruct;
|
|
};
|
|
|
|
struct output_elements {
|
|
QuaternionF quat; // quaternion defining rotation from local NED earth frame to body frame
|
|
Vector3F velocity; // velocity of body frame origin in local NED earth frame (m/sec)
|
|
Vector3F position; // position of body frame origin in local NED earth frame (m)
|
|
};
|
|
|
|
struct imu_elements {
|
|
Vector3F delAng; // IMU delta angle measurements in body frame (rad)
|
|
Vector3F delVel; // IMU delta velocity measurements in body frame (m/sec)
|
|
ftype delAngDT; // time interval over which delAng has been measured (sec)
|
|
ftype delVelDT; // time interval over which delVelDT has been measured (sec)
|
|
uint32_t time_ms; // measurement timestamp (msec)
|
|
uint8_t gyro_index;
|
|
uint8_t accel_index;
|
|
};
|
|
|
|
struct gps_elements : EKF_obs_element_t {
|
|
int32_t lat, lng; // latitude and longitude in 1e7 degrees
|
|
ftype hgt; // height of the GPS antenna in local NED earth frame (m)
|
|
Vector3F vel; // velocity of the GPS antenna in local NED earth frame (m/sec)
|
|
uint8_t sensor_idx; // unique integer identifying the GPS sensor
|
|
bool corrected; // true when the position and velocity have been corrected for sensor position
|
|
bool have_vz; // true when vertical velocity is valid
|
|
};
|
|
|
|
struct mag_elements : EKF_obs_element_t {
|
|
Vector3F mag; // body frame magnetic field measurements (Gauss)
|
|
};
|
|
|
|
struct baro_elements : EKF_obs_element_t {
|
|
ftype hgt; // height of the pressure sensor in local NED earth frame (m)
|
|
};
|
|
|
|
struct range_elements : EKF_obs_element_t {
|
|
ftype rng; // distance measured by the range sensor (m)
|
|
uint8_t sensor_idx; // integer either 0 or 1 uniquely identifying up to two range sensors
|
|
};
|
|
|
|
struct rng_bcn_elements : EKF_obs_element_t {
|
|
ftype rng; // range measurement to each beacon (m)
|
|
Vector3F beacon_posNED; // NED position of the beacon (m)
|
|
ftype rngErr; // range measurement error 1-std (m)
|
|
uint8_t beacon_ID; // beacon identification number
|
|
};
|
|
|
|
struct tas_elements : EKF_obs_element_t {
|
|
ftype tas; // true airspeed measurement (m/sec)
|
|
ftype tasVariance; // variance of true airspeed measurement (m/sec)^2
|
|
bool allowFusion; // true if measurement can be allowed to modify EKF states.
|
|
};
|
|
|
|
struct of_elements : EKF_obs_element_t {
|
|
Vector2F flowRadXY; // raw (non motion compensated) optical flow angular rates about the XY body axes (rad/sec)
|
|
Vector2F flowRadXYcomp; // motion compensated XY optical flow angular rates about the XY body axes (rad/sec)
|
|
Vector3F bodyRadXYZ; // body frame XYZ axis angular rates averaged across the optical flow measurement interval (rad/sec)
|
|
Vector3F body_offset; // XYZ position of the optical flow sensor in body frame (m)
|
|
};
|
|
|
|
struct vel_odm_elements : EKF_obs_element_t {
|
|
Vector3F vel; // XYZ velocity measured in body frame (m/s)
|
|
ftype velErr; // velocity measurement error 1-std (m/s)
|
|
Vector3F body_offset;// XYZ position of the velocity sensor in body frame (m)
|
|
Vector3F angRate; // angular rate estimated from odometry (rad/sec)
|
|
};
|
|
|
|
struct wheel_odm_elements : EKF_obs_element_t {
|
|
ftype delAng; // wheel rotation angle measured in body frame - positive is forward movement of vehicle (rad/s)
|
|
ftype radius; // wheel radius (m)
|
|
Vector3F hub_offset; // XYZ position of the wheel hub in body frame (m)
|
|
ftype delTime; // time interval that the measurement was accumulated over (sec)
|
|
};
|
|
|
|
// Specifies the rotation order used for the Tait-Bryan or Euler angles where alternative rotation orders are available
|
|
enum class rotationOrder {
|
|
TAIT_BRYAN_321=0,
|
|
TAIT_BRYAN_312=1
|
|
};
|
|
|
|
struct yaw_elements : EKF_obs_element_t {
|
|
ftype yawAng; // yaw angle measurement (rad)
|
|
ftype yawAngErr; // yaw angle 1SD measurement accuracy (rad)
|
|
rotationOrder order; // type specifiying Euler rotation order used, 0 = 321 (ZYX), 1 = 312 (ZXY)
|
|
};
|
|
|
|
struct ext_nav_elements : EKF_obs_element_t {
|
|
Vector3F pos; // XYZ position measured in a RH navigation frame (m)
|
|
ftype posErr; // spherical position measurement error 1-std (m)
|
|
bool posReset; // true when the position measurement has been reset
|
|
bool corrected; // true when the position has been corrected for sensor position
|
|
};
|
|
|
|
struct ext_nav_vel_elements : EKF_obs_element_t {
|
|
Vector3F vel; // velocity in NED (m/s)
|
|
ftype err; // velocity measurement error (m/s)
|
|
bool corrected; // true when the velocity has been corrected for sensor position
|
|
};
|
|
|
|
struct drag_elements : EKF_obs_element_t {
|
|
Vector2f accelXY; // measured specific force along the X and Y body axes (m/sec**2)
|
|
};
|
|
|
|
// bias estimates for the IMUs that are enabled but not being used
|
|
// by this core.
|
|
struct {
|
|
Vector3F gyro_bias;
|
|
Vector3F accel_bias;
|
|
} inactiveBias[INS_MAX_INSTANCES];
|
|
|
|
// Specify source of data to be used for a partial state reset
|
|
// Checking the availability and quality of the data source specified is the responsibility of the caller
|
|
enum class resetDataSource {
|
|
DEFAULT=0, // Use data source selected by reset function internal rules
|
|
GPS=1, // Use GPS
|
|
RNGBCN=2, // Use beacon range data
|
|
FLOW=3, // Use optical flow rates
|
|
BARO=4, // Use Baro height
|
|
MAG=5, // Use magnetometer data
|
|
RNGFND=6, // Use rangefinder data
|
|
EXTNAV=7 // Use external nav data
|
|
};
|
|
|
|
// specifies the method to be used when fusing yaw observations
|
|
enum class yawFusionMethod {
|
|
MAGNETOMETER=0,
|
|
GPS=1,
|
|
GSF=2,
|
|
STATIC=3,
|
|
PREDICTED=4,
|
|
EXTNAV=5,
|
|
};
|
|
|
|
// update the navigation filter status
|
|
void updateFilterStatus(void);
|
|
|
|
// update the quaternion, velocity and position states using IMU measurements
|
|
void UpdateStrapdownEquationsNED();
|
|
|
|
// calculate the predicted state covariance matrix
|
|
// Argument rotVarVecPtr is pointer to a vector defining the earth frame uncertainty variance of the quaternion states
|
|
// used to perform a reset of the quaternion state covariances only. Set to null for normal operation.
|
|
void CovariancePrediction(Vector3F *rotVarVecPtr);
|
|
|
|
// force symmetry on the state covariance matrix
|
|
void ForceSymmetry();
|
|
|
|
// constrain variances (diagonal terms) in the state covariance matrix
|
|
void ConstrainVariances();
|
|
|
|
// constrain states
|
|
void ConstrainStates();
|
|
|
|
// constrain earth field using WMM tables
|
|
void MagTableConstrain(void);
|
|
|
|
// fuse selected position, velocity and height measurements
|
|
void FuseVelPosNED();
|
|
|
|
// fuse body frame velocity measurements
|
|
void FuseBodyVel();
|
|
|
|
// fuse range beacon measurements
|
|
void FuseRngBcn();
|
|
|
|
// use range beacon measurements to calculate a static position
|
|
void FuseRngBcnStatic();
|
|
|
|
// calculate the offset from EKF vertical position datum to the range beacon system datum
|
|
void CalcRangeBeaconPosDownOffset(ftype obsVar, Vector3F &vehiclePosNED, bool aligning);
|
|
|
|
// fuse magnetometer measurements
|
|
void FuseMagnetometer();
|
|
|
|
// fuse true airspeed measurements
|
|
void FuseAirspeed();
|
|
|
|
// fuse synthetic sideslip measurement of zero
|
|
void FuseSideslip();
|
|
|
|
// zero specified range of rows in the state covariance matrix
|
|
void zeroRows(Matrix24 &covMat, uint8_t first, uint8_t last);
|
|
|
|
// zero specified range of columns in the state covariance matrix
|
|
void zeroCols(Matrix24 &covMat, uint8_t first, uint8_t last);
|
|
|
|
// Reset the stored output history to current data
|
|
void StoreOutputReset(void);
|
|
|
|
// Reset the stored output quaternion history to current EKF state
|
|
void StoreQuatReset(void);
|
|
|
|
// Rotate the stored output quaternion history through a quaternion rotation
|
|
void StoreQuatRotate(const QuaternionF &deltaQuat);
|
|
|
|
// calculate the NED earth spin vector in rad/sec
|
|
void calcEarthRateNED(Vector3F &omega, int32_t latitude) const;
|
|
|
|
// initialise the covariance matrix
|
|
void CovarianceInit();
|
|
|
|
// helper functions for readIMUData
|
|
bool readDeltaVelocity(uint8_t ins_index, Vector3F &dVel, ftype &dVel_dt);
|
|
bool readDeltaAngle(uint8_t ins_index, Vector3F &dAng, ftype &dAng_dt);
|
|
|
|
// helper functions for correcting IMU data
|
|
void correctDeltaAngle(Vector3F &delAng, ftype delAngDT, uint8_t gyro_index);
|
|
void correctDeltaVelocity(Vector3F &delVel, ftype delVelDT, uint8_t accel_index);
|
|
|
|
// update IMU delta angle and delta velocity measurements
|
|
void readIMUData();
|
|
|
|
// update estimate of inactive bias states
|
|
void learnInactiveBiases();
|
|
|
|
// check for new valid GPS data and update stored measurement if available
|
|
void readGpsData();
|
|
|
|
// check for new valid GPS yaw data
|
|
void readGpsYawData();
|
|
|
|
// check for new altitude measurement data and update stored measurement if available
|
|
void readBaroData();
|
|
|
|
// check for new magnetometer data and update store measurements if available
|
|
void readMagData();
|
|
|
|
// try changing compasses on compass failure or timeout
|
|
void tryChangeCompass(void);
|
|
|
|
// check for new airspeed data and update stored measurements if available
|
|
void readAirSpdData();
|
|
|
|
// check for new range beacon data and update stored measurements if available
|
|
void readRngBcnData();
|
|
|
|
// determine when to perform fusion of GPS position and velocity measurements
|
|
void SelectVelPosFusion();
|
|
|
|
// determine when to perform fusion of range measurements take relative to a beacon at a known NED position
|
|
void SelectRngBcnFusion();
|
|
|
|
// determine when to perform fusion of magnetometer measurements
|
|
void SelectMagFusion();
|
|
|
|
// determine when to perform fusion of true airspeed measurements
|
|
void SelectTasFusion();
|
|
|
|
// determine when to perform fusion of drag or synthetic sideslip measurements
|
|
void SelectBetaDragFusion();
|
|
|
|
// force alignment of the yaw angle using GPS velocity data
|
|
void realignYawGPS();
|
|
|
|
// initialise the earth magnetic field states using declination and current attitude and magnetometer measurements
|
|
|
|
// align the yaw angle for the quaternion states to the given yaw angle which should be at the fusion horizon
|
|
void alignYawAngle(const yaw_elements &yawAngData);
|
|
|
|
// update mag field states and associated variances using magnetomer and declination data
|
|
void resetMagFieldStates();
|
|
|
|
// reset yaw based on magnetic field sample
|
|
void setYawFromMag();
|
|
|
|
// zero stored variables
|
|
void InitialiseVariables();
|
|
|
|
// zero stored variables related to mag
|
|
void InitialiseVariablesMag();
|
|
|
|
// reset the horizontal position states uing the last GPS measurement
|
|
void ResetPosition(resetDataSource posResetSource);
|
|
|
|
// reset the stateStruct's NE position to the specified position
|
|
void ResetPositionNE(ftype posN, ftype posE);
|
|
|
|
// reset the stateStruct's D position
|
|
void ResetPositionD(ftype posD);
|
|
|
|
// reset velocity states using the last GPS measurement
|
|
void ResetVelocity(resetDataSource velResetSource);
|
|
|
|
// reset the vertical position state using the last height measurement
|
|
void ResetHeight(void);
|
|
|
|
// return true if we should use the airspeed sensor
|
|
bool useAirspeed(void) const;
|
|
|
|
// return true if the vehicle code has requested the filter to be ready for flight
|
|
bool readyToUseGPS(void) const;
|
|
|
|
// return true if the filter to be ready to use the beacon range measurements
|
|
bool readyToUseRangeBeacon(void) const;
|
|
|
|
// Check for filter divergence
|
|
void checkDivergence(void);
|
|
|
|
// Calculate weighting that is applied to IMU1 accel data to blend data from IMU's 1 and 2
|
|
void calcIMU_Weighting(ftype K1, ftype K2);
|
|
|
|
// return true if the filter is ready to start using optical flow measurements for position and velocity estimation
|
|
bool readyToUseOptFlow(void) const;
|
|
|
|
// return true if the filter is ready to start using body frame odometry measurements
|
|
bool readyToUseBodyOdm(void) const;
|
|
|
|
// return true if the filter to be ready to use external nav data
|
|
bool readyToUseExtNav(void) const;
|
|
|
|
// return true if we should use the range finder sensor
|
|
bool useRngFinder(void) const;
|
|
|
|
// determine when to perform fusion of optical flow measurements
|
|
void SelectFlowFusion();
|
|
|
|
// determine when to perform fusion of body frame odometry measurements
|
|
void SelectBodyOdomFusion();
|
|
|
|
// Estimate terrain offset using a single state EKF
|
|
void EstimateTerrainOffset(const of_elements &ofDataDelayed);
|
|
|
|
// fuse optical flow measurements into the main filter
|
|
// really_fuse should be true to actually fuse into the main filter, false to only calculate variances
|
|
void FuseOptFlow(const of_elements &ofDataDelayed, bool really_fuse);
|
|
|
|
// Control filter mode changes
|
|
void controlFilterModes();
|
|
|
|
// Determine if we are flying or on the ground
|
|
void detectFlight();
|
|
|
|
// Set inertial navigation aiding mode
|
|
void setAidingMode();
|
|
|
|
// Determine if learning of wind and magnetic field will be enabled and set corresponding indexing limits to
|
|
// avoid unnecessary operations
|
|
void setWindMagStateLearningMode();
|
|
|
|
// Check the alignmnent status of the tilt attitude
|
|
// Used during initial bootstrap alignment of the filter
|
|
void checkAttitudeAlignmentStatus();
|
|
|
|
// Control reset of yaw and magnetic field states
|
|
void controlMagYawReset();
|
|
|
|
// set the latitude and longitude and height used to set the NED origin
|
|
// All NED positions calculated by the filter will be relative to this location
|
|
// returns false if the origin has already been set
|
|
bool setOrigin(const Location &loc);
|
|
|
|
// Assess GPS data quality and set gpsGoodToAlign
|
|
void calcGpsGoodToAlign(void);
|
|
|
|
// set the class variable true if the delta angle bias variances are sufficiently small
|
|
void checkGyroCalStatus(void);
|
|
|
|
// update inflight calculaton that determines if GPS data is good enough for reliable navigation
|
|
void calcGpsGoodForFlight(void);
|
|
|
|
// Read the range finder and take new measurements if available
|
|
// Apply a median filter to range finder data
|
|
void readRangeFinder();
|
|
|
|
// check if the vehicle has taken off during optical flow navigation by looking at inertial and range finder data
|
|
void detectOptFlowTakeoff(void);
|
|
|
|
// align the NE earth magnetic field states with the published declination
|
|
void alignMagStateDeclination();
|
|
|
|
// Fuse compass measurements using a direct yaw angle observation (doesn't require magnetic field states)
|
|
// Returns true if the fusion was successful
|
|
bool fuseEulerYaw(yawFusionMethod method);
|
|
|
|
// return the best Tait-Bryan rotation order to use
|
|
void bestRotationOrder(rotationOrder &order);
|
|
|
|
// Fuse declination angle to keep earth field declination from changing when we don't have earth relative observations.
|
|
// Input is 1-sigma uncertainty in published declination
|
|
void FuseDeclination(ftype declErr);
|
|
|
|
// return magnetic declination in radians
|
|
ftype MagDeclination(void) const;
|
|
|
|
// Propagate PVA solution forward from the fusion time horizon to the current time horizon
|
|
// using a simple observer
|
|
void calcOutputStates();
|
|
|
|
// calculate a filtered offset between baro height measurement and EKF height estimate
|
|
void calcFiltBaroOffset();
|
|
|
|
// correct the height of the EKF origin to be consistent with GPS Data using a Bayes filter.
|
|
void correctEkfOriginHeight();
|
|
|
|
// Select height data to be fused from the available baro, range finder and GPS sources
|
|
void selectHeightForFusion();
|
|
|
|
// zero attitude state covariances, but preserve variances
|
|
void zeroAttCovOnly();
|
|
|
|
// record a yaw reset event
|
|
void recordYawReset();
|
|
|
|
// record a magnetic field state reset event
|
|
void recordMagReset();
|
|
|
|
// effective value of MAG_CAL
|
|
MagCal effective_magCal(void) const;
|
|
|
|
// calculate the tilt error variance
|
|
void calcTiltErrorVariance(void);
|
|
|
|
#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
|
|
// calculate the tilt error variance using an alternative numerical difference technique
|
|
// and log with value generated by NavEKF3_core::calcTiltErrorVariance()
|
|
void verifyTiltErrorVariance();
|
|
#endif
|
|
|
|
// update timing statistics structure
|
|
void updateTimingStatistics(void);
|
|
|
|
// Update the state index limit based on which states are active
|
|
void updateStateIndexLim(void);
|
|
|
|
// correct GPS data for antenna position
|
|
void CorrectGPSForAntennaOffset(gps_elements &gps_data) const;
|
|
|
|
// correct external navigation earth-frame position using sensor body-frame offset
|
|
void CorrectExtNavForSensorOffset(ext_nav_elements &ext_nav_data);
|
|
|
|
// correct external navigation earth-frame velocity using sensor body-frame offset
|
|
void CorrectExtNavVelForSensorOffset(ext_nav_vel_elements &ext_nav_vel_data) const;
|
|
|
|
// calculate velocity variances and innovations
|
|
// Scale factor applied to NE velocity measurement variance due to manoeuvre acceleration
|
|
// Scale factor applied to vertical velocity measurement variance due to manoeuvre acceleration
|
|
// variances argument is updated with variances for each axis
|
|
void CalculateVelInnovationsAndVariances(const Vector3F &velocity, ftype noise, ftype accel_scale, Vector3F &innovations, Vector3F &variances) const;
|
|
|
|
// Runs the IMU prediction step for an independent GSF yaw estimator algorithm
|
|
// that uses IMU, GPS horizontal velocity and optionally true airspeed data.
|
|
void runYawEstimatorPrediction(void);
|
|
|
|
// Run the GPS velocity correction step for the GSF yaw estimator and use the
|
|
// yaw estimate to reset the main EKF yaw if requested
|
|
void runYawEstimatorCorrection(void);
|
|
|
|
// reset the quaternion states using the supplied yaw angle, maintaining the previous roll and pitch
|
|
// also reset the body to nav frame rotation matrix
|
|
// reset the quaternion state covariances using the supplied yaw variance
|
|
// yaw : new yaw angle (rad)
|
|
// yaw_variance : variance of new yaw angle (rad^2)
|
|
// order : enum defining Tait-Bryan rotation order used in calculation of the yaw angle
|
|
void resetQuatStateYawOnly(ftype yaw, ftype yawVariance, rotationOrder order);
|
|
|
|
// attempt to reset the yaw to the EKF-GSF value
|
|
// emergency_reset should be true if this reset is triggered by the loss of the yaw estimate
|
|
// returns false if unsuccessful
|
|
bool EKFGSF_resetMainFilterYaw(bool emergency_reset);
|
|
|
|
// returns true on success and populates yaw (in radians) and yawVariance (rad^2)
|
|
bool EKFGSF_getYaw(ftype &yaw, ftype &yawVariance) const;
|
|
|
|
// Fusion of body frame X and Y axis drag specific forces for multi-rotor wind estimation
|
|
void FuseDragForces();
|
|
void SelectDragFusion();
|
|
void SampleDragData(const imu_elements &imu);
|
|
|
|
bool getGPSLLH(struct Location &loc) const;
|
|
|
|
// Variables
|
|
bool statesInitialised; // boolean true when filter states have been initialised
|
|
bool magHealth; // boolean true if magnetometer has passed innovation consistency check
|
|
bool velTimeout; // boolean true if velocity measurements have failed innovation consistency check and timed out
|
|
bool posTimeout; // boolean true if position measurements have failed innovation consistency check and timed out
|
|
bool hgtTimeout; // boolean true if height measurements have failed innovation consistency check and timed out
|
|
bool magTimeout; // boolean true if magnetometer measurements have failed for too long and have timed out
|
|
bool tasTimeout; // boolean true if true airspeed measurements have failed for too long and have timed out
|
|
bool dragTimeout; // boolean true if drag measurements have failed for too long and have timed out
|
|
bool badIMUdata; // boolean true if the bad IMU data is detected
|
|
uint32_t badIMUdata_ms; // time stamp bad IMU data was last detected
|
|
uint32_t goodIMUdata_ms; // time stamp good IMU data was last detected
|
|
uint32_t vertVelVarClipCounter; // counter used to control reset of vertical velocity variance following collapse against the lower limit
|
|
|
|
ftype gpsNoiseScaler; // Used to scale the GPS measurement noise and consistency gates to compensate for operation with small satellite counts
|
|
Matrix24 P; // covariance matrix
|
|
EKF_IMU_buffer_t<imu_elements> storedIMU; // IMU data buffer
|
|
EKF_obs_buffer_t<gps_elements> storedGPS; // GPS data buffer
|
|
EKF_obs_buffer_t<mag_elements> storedMag; // Magnetometer data buffer
|
|
EKF_obs_buffer_t<baro_elements> storedBaro; // Baro data buffer
|
|
EKF_obs_buffer_t<tas_elements> storedTAS; // TAS data buffer
|
|
EKF_obs_buffer_t<range_elements> storedRange; // Range finder data buffer
|
|
EKF_IMU_buffer_t<output_elements> storedOutput;// output state buffer
|
|
Matrix3F prevTnb; // previous nav to body transformation used for INS earth rotation compensation
|
|
ftype accNavMag; // magnitude of navigation accel - used to adjust GPS obs variance (m/s^2)
|
|
ftype accNavMagHoriz; // magnitude of navigation accel in horizontal plane (m/s^2)
|
|
Vector3F earthRateNED; // earths angular rate vector in NED (rad/s)
|
|
ftype dtIMUavg; // expected time between IMU measurements (sec)
|
|
ftype dtEkfAvg; // expected time between EKF updates (sec)
|
|
ftype dt; // time lapsed since the last covariance prediction (sec)
|
|
ftype hgtRate; // state for rate of change of height filter
|
|
bool onGround; // true when the flight vehicle is definitely on the ground
|
|
bool prevOnGround; // value of onGround from previous frame - used to detect transition
|
|
bool inFlight; // true when the vehicle is definitely flying
|
|
bool prevInFlight; // value inFlight from previous frame - used to detect transition
|
|
bool manoeuvring; // boolean true when the flight vehicle is performing horizontal changes in velocity
|
|
Vector6 innovVelPos; // innovation output for a group of measurements
|
|
Vector6 varInnovVelPos; // innovation variance output for a group of measurements
|
|
Vector6 velPosObs; // observations for combined velocity and positon group of measurements (3x1 m , 3x1 m/s)
|
|
bool fuseVelData; // this boolean causes the velNED measurements to be fused
|
|
bool fusePosData; // this boolean causes the posNE measurements to be fused
|
|
bool fuseHgtData; // this boolean causes the hgtMea measurements to be fused
|
|
Vector3F innovMag; // innovation output from fusion of X,Y,Z compass measurements
|
|
Vector3F varInnovMag; // innovation variance output from fusion of X,Y,Z compass measurements
|
|
ftype innovVtas; // innovation output from fusion of airspeed measurements
|
|
ftype varInnovVtas; // innovation variance output from fusion of airspeed measurements
|
|
ftype defaultAirSpeed; // default equivalent airspeed in m/s to be used if the measurement is unavailable. Do not use if not positive.
|
|
ftype defaultAirSpeedVariance; // default equivalent airspeed variance in (m/s)**2 to be used when defaultAirSpeed is specified.
|
|
bool magFusePerformed; // boolean set to true when magnetometer fusion has been perfomred in that time step
|
|
MagCal effectiveMagCal; // the actual mag calibration being used as the default
|
|
uint32_t prevTasStep_ms; // time stamp of last TAS fusion step
|
|
uint32_t prevBetaDragStep_ms; // time stamp of last synthetic sideslip fusion step
|
|
ftype innovBeta; // synthetic sideslip innovation (rad)
|
|
uint32_t lastMagUpdate_us; // last time compass was updated in usec
|
|
uint32_t lastMagRead_ms; // last time compass data was successfully read
|
|
Vector3F velDotNED; // rate of change of velocity in NED frame
|
|
Vector3F velDotNEDfilt; // low pass filtered velDotNED
|
|
uint32_t imuSampleTime_ms; // time that the last IMU value was taken
|
|
bool tasDataToFuse; // true when new airspeed data is waiting to be fused
|
|
uint32_t lastBaroReceived_ms; // time last time we received baro height data
|
|
uint16_t hgtRetryTime_ms; // time allowed without use of height measurements before a height timeout is declared
|
|
uint32_t lastVelPassTime_ms; // time stamp when GPS velocity measurement last passed innovation consistency check (msec)
|
|
uint32_t lastPosPassTime_ms; // time stamp when GPS position measurement last passed innovation consistency check (msec)
|
|
uint32_t lastHgtPassTime_ms; // time stamp when height measurement last passed innovation consistency check (msec)
|
|
uint32_t lastTasPassTime_ms; // time stamp when airspeed measurement last passed innovation consistency check (msec)
|
|
uint32_t lastTasFailTime_ms; // time stamp when airspeed measurement last failed innovation consistency check (msec)
|
|
uint32_t lastTimeGpsReceived_ms;// last time we received GPS data
|
|
uint32_t timeAtLastAuxEKF_ms; // last time the auxiliary filter was run to fuse range or optical flow measurements
|
|
uint32_t lastHealthyMagTime_ms; // time the magnetometer was last declared healthy
|
|
bool allMagSensorsFailed; // true if all magnetometer sensors have timed out on this flight and we are no longer using magnetometer data
|
|
uint32_t lastSynthYawTime_ms; // time stamp when yaw observation was last fused (msec)
|
|
uint32_t ekfStartTime_ms; // time the EKF was started (msec)
|
|
Vector2F lastKnownPositionNE; // last known position
|
|
float lastKnownPositionD; // last known height
|
|
uint32_t lastLaunchAccelTime_ms;
|
|
ftype velTestRatio; // sum of squares of GPS velocity innovation divided by fail threshold
|
|
ftype posTestRatio; // sum of squares of GPS position innovation divided by fail threshold
|
|
ftype hgtTestRatio; // sum of squares of baro height innovation divided by fail threshold
|
|
Vector3F magTestRatio; // sum of squares of magnetometer innovations divided by fail threshold
|
|
ftype tasTestRatio; // sum of squares of true airspeed innovation divided by fail threshold
|
|
bool inhibitWindStates; // true when wind states and covariances are to remain constant
|
|
bool windStatesAligned; // true when wind states have been aligned
|
|
bool inhibitMagStates; // true when magnetic field states are inactive
|
|
bool lastInhibitMagStates; // previous inhibitMagStates
|
|
bool needMagBodyVarReset; // we need to reset mag body variances at next CovariancePrediction
|
|
bool needEarthBodyVarReset; // we need to reset mag earth variances at next CovariancePrediction
|
|
bool inhibitDelAngBiasStates; // true when IMU delta angle bias states are inactive
|
|
bool gpsIsInUse; // bool true when GPS data is being used to correct states estimates
|
|
struct Location EKF_origin; // LLH origin of the NED axis system, internal only
|
|
struct Location &public_origin; // LLH origin of the NED axis system, public functions
|
|
bool validOrigin; // true when the EKF origin is valid
|
|
ftype gpsSpdAccuracy; // estimated speed accuracy in m/s returned by the GPS receiver
|
|
ftype gpsPosAccuracy; // estimated position accuracy in m returned by the GPS receiver
|
|
ftype gpsHgtAccuracy; // estimated height accuracy in m returned by the GPS receiver
|
|
uint32_t lastGpsVelFail_ms; // time of last GPS vertical velocity consistency check fail
|
|
uint32_t lastGpsVelPass_ms; // time of last GPS vertical velocity consistency check pass
|
|
uint32_t lastGpsAidBadTime_ms; // time in msec gps aiding was last detected to be bad
|
|
ftype posDownAtTakeoff; // flight vehicle vertical position sampled at transition from on-ground to in-air and used as a reference (m)
|
|
bool useGpsVertVel; // true if GPS vertical velocity should be used
|
|
ftype yawResetAngle; // Change in yaw angle due to last in-flight yaw reset in radians. A positive value means the yaw angle has increased.
|
|
uint32_t lastYawReset_ms; // System time at which the last yaw reset occurred. Returned by getLastYawResetAngle
|
|
bool tiltAlignComplete; // true when tilt alignment is complete
|
|
bool yawAlignComplete; // true when yaw alignment is complete
|
|
bool magStateInitComplete; // true when the magnetic field states have been initialised
|
|
uint8_t stateIndexLim; // Max state index used during matrix and array operations
|
|
imu_elements imuDataDelayed; // IMU data at the fusion time horizon
|
|
imu_elements imuDataNew; // IMU data at the current time horizon
|
|
imu_elements imuDataDownSampledNew; // IMU data at the current time horizon that has been downsampled to a 100Hz rate
|
|
QuaternionF imuQuatDownSampleNew; // Quaternion obtained by rotating through the IMU delta angles since the start of the current down sampled frame
|
|
baro_elements baroDataNew; // Baro data at the current time horizon
|
|
baro_elements baroDataDelayed; // Baro data at the fusion time horizon
|
|
range_elements rangeDataNew; // Range finder data at the current time horizon
|
|
range_elements rangeDataDelayed;// Range finder data at the fusion time horizon
|
|
tas_elements tasDataNew; // TAS data at the current time horizon
|
|
tas_elements tasDataDelayed; // TAS data at the fusion time horizon
|
|
bool usingDefaultAirspeed; // true when a default airspeed is being used instead of a measured value
|
|
mag_elements magDataDelayed; // Magnetometer data at the fusion time horizon
|
|
gps_elements gpsDataNew; // GPS data at the current time horizon
|
|
gps_elements gpsDataDelayed; // GPS data at the fusion time horizon
|
|
uint8_t last_gps_idx; // sensor ID of the GPS receiver used for the last fusion or reset
|
|
output_elements outputDataNew; // output state data at the current time step
|
|
output_elements outputDataDelayed; // output state data at the current time step
|
|
Vector3F delAngCorrection; // correction applied to delta angles used by output observer to track the EKF
|
|
Vector3F velErrintegral; // integral of output predictor NED velocity tracking error (m)
|
|
Vector3F posErrintegral; // integral of output predictor NED position tracking error (m.sec)
|
|
ftype badImuVelErrIntegral; // integral of output predictor D velocity tracking error when bad IMU data is detected (m)
|
|
ftype innovYaw; // compass yaw angle innovation (rad)
|
|
uint32_t timeTasReceived_ms; // time last TAS data was received (msec)
|
|
bool gpsGoodToAlign; // true when the GPS quality can be used to initialise the navigation system
|
|
uint32_t magYawResetTimer_ms; // timer in msec used to track how long good magnetometer data is failing innovation consistency checks
|
|
bool consistentMagData; // true when the magnetometers are passing consistency checks
|
|
bool motorsArmed; // true when the motors have been armed
|
|
bool prevMotorsArmed; // value of motorsArmed from previous frame
|
|
bool posVelFusionDelayed; // true when the position and velocity fusion has been delayed
|
|
bool optFlowFusionDelayed; // true when the optical flow fusion has been delayed
|
|
bool airSpdFusionDelayed; // true when the air speed fusion has been delayed
|
|
bool sideSlipFusionDelayed; // true when the sideslip fusion has been delayed
|
|
bool airDataFusionWindOnly; // true when sideslip and airspeed fusion is only allowed to modify the wind states
|
|
Vector3F lastMagOffsets; // Last magnetometer offsets from COMPASS_ parameters. Used to detect parameter changes.
|
|
bool lastMagOffsetsValid; // True when lastMagOffsets has been initialized
|
|
Vector2F posResetNE; // Change in North/East position due to last in-flight reset in metres. Returned by getLastPosNorthEastReset
|
|
uint32_t lastPosReset_ms; // System time at which the last position reset occurred. Returned by getLastPosNorthEastReset
|
|
Vector2F velResetNE; // Change in North/East velocity due to last in-flight reset in metres/sec. Returned by getLastVelNorthEastReset
|
|
uint32_t lastVelReset_ms; // System time at which the last velocity reset occurred. Returned by getLastVelNorthEastReset
|
|
ftype posResetD; // Change in Down position due to last in-flight reset in metres. Returned by getLastPosDowntReset
|
|
uint32_t lastPosResetD_ms; // System time at which the last position reset occurred. Returned by getLastPosDownReset
|
|
ftype yawTestRatio; // square of magnetometer yaw angle innovation divided by fail threshold
|
|
QuaternionF prevQuatMagReset; // Quaternion from the last time the magnetic field state reset condition test was performed
|
|
ftype hgtInnovFiltState; // state used for fitering of the height innovations used for pre-flight checks
|
|
uint8_t magSelectIndex; // Index of the magnetometer that is being used by the EKF
|
|
bool runUpdates; // boolean true when the EKF updates can be run
|
|
uint32_t framesSincePredict; // number of frames lapsed since EKF instance did a state prediction
|
|
bool startPredictEnabled; // boolean true when the frontend has given permission to start a new state prediciton cycle
|
|
uint8_t localFilterTimeStep_ms; // average number of msec between filter updates
|
|
ftype posDownObsNoise; // observation noise variance on the vertical position used by the state and covariance update step (m^2)
|
|
Vector3F delAngCorrected; // corrected IMU delta angle vector at the EKF time horizon (rad)
|
|
Vector3F delVelCorrected; // corrected IMU delta velocity vector at the EKF time horizon (m/s)
|
|
bool magFieldLearned; // true when the magnetic field has been learned
|
|
uint32_t wasLearningCompass_ms; // time when we were last waiting for compass learn to complete
|
|
Vector3F earthMagFieldVar; // NED earth mag field variances for last learned field (mGauss^2)
|
|
Vector3F bodyMagFieldVar; // XYZ body mag field variances for last learned field (mGauss^2)
|
|
bool delAngBiasLearned; // true when the gyro bias has been learned
|
|
nav_filter_status filterStatus; // contains the status of various filter outputs
|
|
ftype ekfOriginHgtVar; // Variance of the EKF WGS-84 origin height estimate (m^2)
|
|
double ekfGpsRefHgt; // floating point representation of the WGS-84 reference height used to convert GPS height to local height (m)
|
|
uint32_t lastOriginHgtTime_ms; // last time the ekf's WGS-84 origin height was corrected
|
|
Vector3F outputTrackError; // attitude (rad), velocity (m/s) and position (m) tracking error magnitudes from the output observer
|
|
Vector3F velOffsetNED; // This adds to the earth frame velocity estimate at the IMU to give the velocity at the body origin (m/s)
|
|
Vector3F posOffsetNED; // This adds to the earth frame position estimate at the IMU to give the position at the body origin (m)
|
|
uint32_t firstInitTime_ms; // First time the initialise function was called (msec)
|
|
uint32_t lastInitFailReport_ms; // Last time the buffer initialisation failure report was sent (msec)
|
|
ftype tiltErrorVariance; // variance of the angular uncertainty measured perpendicular to the vertical (rad^2)
|
|
|
|
// variables used to calculate a vertical velocity that is kinematically consistent with the vertical position
|
|
struct {
|
|
ftype pos;
|
|
ftype vel;
|
|
ftype acc;
|
|
} vertCompFiltState;
|
|
|
|
// variables used by the pre-initialisation GPS checks
|
|
struct Location gpsloc_prev; // LLH location of previous GPS measurement
|
|
uint32_t lastPreAlignGpsCheckTime_ms; // last time in msec the GPS quality was checked during pre alignment checks
|
|
ftype gpsDriftNE; // amount of drift detected in the GPS position during pre-flight GPs checks
|
|
ftype gpsVertVelFilt; // amount of filtered vertical GPS velocity detected during pre-flight GPS checks
|
|
ftype gpsHorizVelFilt; // amount of filtered horizontal GPS velocity detected during pre-flight GPS checks
|
|
|
|
// variable used by the in-flight GPS quality check
|
|
bool gpsSpdAccPass; // true when reported GPS speed accuracy passes in-flight checks
|
|
bool gpsVertAccPass; // true when reported GPS vertical accuracy passes in-flight checks
|
|
bool ekfInnovationsPass; // true when GPS innovations pass in-flight checks
|
|
ftype sAccFilterState1; // state variable for LPF applied to reported GPS speed accuracy
|
|
ftype sAccFilterState2; // state variable for peak hold filter applied to reported GPS speed
|
|
uint32_t lastGpsCheckTime_ms; // last time in msec the GPS quality was checked
|
|
uint32_t lastGpsInnovPassTime_ms; // last time in msec the GPS innovations passed
|
|
uint32_t lastGpsInnovFailTime_ms; // last time in msec the GPS innovations failed
|
|
uint32_t lastGpsVertAccPassTime_ms; // last time in msec the GPS vertical accuracy test passed
|
|
uint32_t lastGpsVertAccFailTime_ms; // last time in msec the GPS vertical accuracy test failed
|
|
bool gpsAccuracyGood; // true when the GPS accuracy is considered to be good enough for safe flight.
|
|
bool gpsAccuracyGoodForAltitude; // true when the GPS accuracy is considered to be good enough to use it as an altitude source.
|
|
Vector3F gpsVelInnov; // gps velocity innovations
|
|
Vector3F gpsVelVarInnov; // gps velocity innovation variances
|
|
uint32_t gpsVelInnovTime_ms; // system time that gps velocity innovations were recorded (to detect timeouts)
|
|
|
|
// variables added for optical flow fusion
|
|
EKF_obs_buffer_t<of_elements> storedOF; // OF data buffer
|
|
bool flowDataValid; // true while optical flow data is still fresh
|
|
Vector2F auxFlowObsInnov; // optical flow rate innovation from 1-state terrain offset estimator
|
|
uint32_t flowValidMeaTime_ms; // time stamp from latest valid flow measurement (msec)
|
|
uint32_t rngValidMeaTime_ms; // time stamp from latest valid range measurement (msec)
|
|
uint32_t flowMeaTime_ms; // time stamp from latest flow measurement (msec)
|
|
uint32_t gndHgtValidTime_ms; // time stamp from last terrain offset state update (msec)
|
|
Vector2 flowVarInnov; // optical flow innovations variances (rad/sec)^2
|
|
Vector2 flowInnov; // optical flow LOS innovations (rad/sec)
|
|
uint32_t flowInnovTime_ms; // system time that optical flow innovations and variances were recorded (to detect timeouts)
|
|
ftype Popt; // Optical flow terrain height state covariance (m^2)
|
|
ftype terrainState; // terrain position state (m)
|
|
ftype prevPosN; // north position at last measurement
|
|
ftype prevPosE; // east position at last measurement
|
|
ftype varInnovRng; // range finder observation innovation variance (m^2)
|
|
ftype innovRng; // range finder observation innovation (m)
|
|
struct {
|
|
uint32_t timestamp_ms; // system timestamp of last correct optical flow sample (used for calibration)
|
|
Vector2f flowRate; // latest corrected optical flow flow rate (used for calibration)
|
|
Vector2f bodyRate; // latest corrected optical flow body rate (used for calibration)
|
|
Vector2f losPred; // EKF estimated component of flowRate that comes from vehicle movement (not rotation)
|
|
} flowCalSample;
|
|
|
|
ftype hgtMea; // height measurement derived from either baro, gps or range finder data (m)
|
|
bool inhibitGndState; // true when the terrain position state is to remain constant
|
|
uint32_t prevFlowFuseTime_ms; // time both flow measurement components passed their innovation consistency checks
|
|
Vector2 flowTestRatio; // square of optical flow innovations divided by fail threshold used by main filter where >1.0 is a fail
|
|
Vector2F auxFlowTestRatio; // sum of squares of optical flow innovation divided by fail threshold used by 1-state terrain offset estimator
|
|
ftype R_LOS; // variance of optical flow rate measurements (rad/sec)^2
|
|
ftype auxRngTestRatio; // square of range finder innovations divided by fail threshold used by main filter where >1.0 is a fail
|
|
Vector2F flowGyroBias; // bias error of optical flow sensor gyro output
|
|
bool rangeDataToFuse; // true when valid range finder height data has arrived at the fusion time horizon.
|
|
bool baroDataToFuse; // true when valid baro height finder data has arrived at the fusion time horizon.
|
|
bool gpsDataToFuse; // true when valid GPS data has arrived at the fusion time horizon.
|
|
bool magDataToFuse; // true when valid magnetometer data has arrived at the fusion time horizon
|
|
enum AidingMode {AID_ABSOLUTE=0, // GPS or some other form of absolute position reference aiding is being used (optical flow may also be used in parallel) so position estimates are absolute.
|
|
AID_NONE=1, // no aiding is being used so only attitude and height estimates are available. Either constVelMode or constPosMode must be used to constrain tilt drift.
|
|
AID_RELATIVE=2 // only optical flow aiding is being used so position estimates will be relative
|
|
};
|
|
AidingMode PV_AidingMode; // Defines the preferred mode for aiding of velocity and position estimates from the INS
|
|
AidingMode PV_AidingModePrev; // Value of PV_AidingMode from the previous frame - used to detect transitions
|
|
bool gndOffsetValid; // true when the ground offset state can still be considered valid
|
|
Vector3F delAngBodyOF; // bias corrected delta angle of the vehicle IMU measured summed across the time since the last OF measurement
|
|
ftype delTimeOF; // time that delAngBodyOF is summed across
|
|
bool flowFusionActive; // true when optical flow fusion is active
|
|
|
|
Vector3F accelPosOffset; // position of IMU accelerometer unit in body frame (m)
|
|
|
|
// Range finder
|
|
ftype baroHgtOffset; // offset applied when when switching to use of Baro height
|
|
ftype rngOnGnd; // Expected range finder reading in metres when vehicle is on ground
|
|
ftype storedRngMeas[2][3]; // Ringbuffer of stored range measurements for dual range sensors
|
|
uint32_t storedRngMeasTime_ms[2][3]; // Ringbuffers of stored range measurement times for dual range sensors
|
|
uint32_t lastRngMeasTime_ms; // Timestamp of last range measurement
|
|
uint8_t rngMeasIndex[2]; // Current range measurement ringbuffer index for dual range sensors
|
|
bool terrainHgtStable; // true when the terrain height is stable enough to be used as a height reference
|
|
|
|
// body frame odometry fusion
|
|
#if EK3_FEATURE_BODY_ODOM
|
|
EKF_obs_buffer_t<vel_odm_elements> storedBodyOdm; // body velocity data buffer
|
|
vel_odm_elements bodyOdmDataNew; // Body frame odometry data at the current time horizon
|
|
vel_odm_elements bodyOdmDataDelayed; // Body frame odometry data at the fusion time horizon
|
|
#endif
|
|
uint32_t lastbodyVelPassTime_ms; // time stamp when the body velocity measurement last passed innovation consistency checks (msec)
|
|
Vector3 bodyVelTestRatio; // Innovation test ratios for body velocity XYZ measurements
|
|
Vector3 varInnovBodyVel; // Body velocity XYZ innovation variances (m/sec)^2
|
|
Vector3 innovBodyVel; // Body velocity XYZ innovations (m/sec)
|
|
uint32_t prevBodyVelFuseTime_ms; // previous time all body velocity measurement components passed their innovation consistency checks (msec)
|
|
uint32_t bodyOdmMeasTime_ms; // time body velocity measurements were accepted for input to the data buffer (msec)
|
|
bool bodyVelFusionDelayed; // true when body frame velocity fusion has been delayed
|
|
bool bodyVelFusionActive; // true when body frame velocity fusion is active
|
|
|
|
#if EK3_FEATURE_BODY_ODOM
|
|
// wheel sensor fusion
|
|
EKF_obs_buffer_t<wheel_odm_elements> storedWheelOdm; // body velocity data buffer
|
|
wheel_odm_elements wheelOdmDataDelayed; // Body frame odometry data at the fusion time horizon
|
|
#endif
|
|
|
|
// GPS yaw sensor fusion
|
|
uint32_t yawMeasTime_ms; // system time GPS yaw angle was last input to the data buffer
|
|
EKF_obs_buffer_t<yaw_elements> storedYawAng; // GPS yaw angle buffer
|
|
yaw_elements yawAngDataNew; // GPS yaw angle at the current time horizon
|
|
yaw_elements yawAngDataDelayed; // GPS yaw angle at the fusion time horizon
|
|
yaw_elements yawAngDataStatic; // yaw angle (regardless of yaw source) when the vehicle was last on ground and not moving
|
|
|
|
// Range Beacon Sensor Fusion
|
|
EKF_obs_buffer_t<rng_bcn_elements> storedRangeBeacon; // Beacon range buffer
|
|
rng_bcn_elements rngBcnDataDelayed; // Range beacon data at the fusion time horizon
|
|
uint32_t lastRngBcnPassTime_ms; // time stamp when the range beacon measurement last passed innovation consistency checks (msec)
|
|
ftype rngBcnTestRatio; // Innovation test ratio for range beacon measurements
|
|
bool rngBcnHealth; // boolean true if range beacon measurements have passed innovation consistency check
|
|
ftype varInnovRngBcn; // range beacon observation innovation variance (m^2)
|
|
ftype innovRngBcn; // range beacon observation innovation (m)
|
|
uint32_t lastTimeRngBcn_ms[4]; // last time we received a range beacon measurement (msec)
|
|
bool rngBcnDataToFuse; // true when there is new range beacon data to fuse
|
|
Vector3F beaconVehiclePosNED; // NED position estimate from the beacon system (NED)
|
|
ftype beaconVehiclePosErr; // estimated position error from the beacon system (m)
|
|
uint32_t rngBcnLast3DmeasTime_ms; // last time the beacon system returned a 3D fix (msec)
|
|
bool rngBcnGoodToAlign; // true when the range beacon systems 3D fix can be used to align the filter
|
|
uint8_t lastRngBcnChecked; // index of the last range beacon checked for data
|
|
Vector3F receiverPos; // receiver NED position (m) - alignment 3 state filter
|
|
ftype receiverPosCov[3][3]; // Receiver position covariance (m^2) - alignment 3 state filter (
|
|
bool rngBcnAlignmentStarted; // True when the initial position alignment using range measurements has started
|
|
bool rngBcnAlignmentCompleted; // True when the initial position alignment using range measurements has finished
|
|
uint8_t lastBeaconIndex; // Range beacon index last read - used during initialisation of the 3-state filter
|
|
Vector3F rngBcnPosSum; // Sum of range beacon NED position (m) - used during initialisation of the 3-state filter
|
|
uint8_t numBcnMeas; // Number of beacon measurements - used during initialisation of the 3-state filter
|
|
ftype rngSum; // Sum of range measurements (m) - used during initialisation of the 3-state filter
|
|
uint8_t N_beacons; // Number of range beacons in use
|
|
ftype maxBcnPosD; // maximum position of all beacons in the down direction (m)
|
|
ftype minBcnPosD; // minimum position of all beacons in the down direction (m)
|
|
bool usingMinHypothesis; // true when the min beacon constellation offset hypothesis is being used
|
|
|
|
ftype bcnPosDownOffsetMax; // Vertical position offset of the beacon constellation origin relative to the EKF origin (m)
|
|
ftype bcnPosOffsetMaxVar; // Variance of the bcnPosDownOffsetMax state (m)
|
|
ftype maxOffsetStateChangeFilt; // Filtered magnitude of the change in bcnPosOffsetHigh
|
|
|
|
ftype bcnPosDownOffsetMin; // Vertical position offset of the beacon constellation origin relative to the EKF origin (m)
|
|
ftype bcnPosOffsetMinVar; // Variance of the bcnPosDownOffsetMin state (m)
|
|
ftype minOffsetStateChangeFilt; // Filtered magnitude of the change in bcnPosOffsetLow
|
|
|
|
Vector3F bcnPosOffsetNED; // NED position of the beacon origin in earth frame (m)
|
|
bool bcnOriginEstInit; // True when the beacon origin has been initialised
|
|
|
|
// Range Beacon Fusion Debug Reporting
|
|
uint8_t rngBcnFuseDataReportIndex;// index of range beacon fusion data last reported
|
|
struct rngBcnFusionReport_t {
|
|
ftype rng; // measured range to beacon (m)
|
|
ftype innov; // range innovation (m)
|
|
ftype innovVar; // innovation variance (m^2)
|
|
ftype testRatio; // innovation consistency test ratio
|
|
Vector3F beaconPosNED; // beacon NED position
|
|
} *rngBcnFusionReport;
|
|
|
|
#if EK3_FEATURE_DRAG_FUSION
|
|
// drag fusion for multicopter wind estimation
|
|
EKF_obs_buffer_t<drag_elements> storedDrag;
|
|
drag_elements dragSampleDelayed;
|
|
drag_elements dragDownSampled; // down sampled from filter prediction rate to observation rate
|
|
uint8_t dragSampleCount; // number of drag specific force samples accumulated at the filter prediction rate
|
|
ftype dragSampleTimeDelta; // time integral across all samples used to form _drag_down_sampled (sec)
|
|
Vector2F innovDrag; // multirotor drag measurement innovation (m/sec**2)
|
|
Vector2F innovDragVar; // multirotor drag measurement innovation variance ((m/sec**2)**2)
|
|
Vector2F dragTestRatio; // drag innovation consistency check ratio
|
|
#endif
|
|
uint32_t lastDragPassTime_ms; // system time that drag samples were last successfully fused
|
|
bool dragFusionEnabled;
|
|
|
|
// height source selection logic
|
|
AP_NavEKF_Source::SourceZ activeHgtSource; // active height source
|
|
AP_NavEKF_Source::SourceZ prevHgtSource; // previous height source used to detect changes in source
|
|
|
|
// Movement detector
|
|
bool takeOffDetected; // true when takeoff for optical flow navigation has been detected
|
|
ftype rngAtStartOfFlight; // range finder measurement at start of flight
|
|
uint32_t timeAtArming_ms; // time in msec that the vehicle armed
|
|
|
|
// baro ground effect
|
|
ftype meaHgtAtTakeOff; // height measured at commencement of takeoff
|
|
|
|
// control of post takeoff magnetic field and heading resets
|
|
bool finalInflightYawInit; // true when the final post takeoff initialisation of yaw angle has been performed
|
|
uint8_t magYawAnomallyCount; // Number of times the yaw has been reset due to a magnetic anomaly during initial ascent
|
|
bool finalInflightMagInit; // true when the final post takeoff initialisation of magnetic field states been performed
|
|
bool magStateResetRequest; // true if magnetic field states need to be reset using the magnetomter measurements
|
|
bool magYawResetRequest; // true if the vehicle yaw and magnetic field states need to be reset using the magnetometer measurements
|
|
bool gpsYawResetRequest; // true if the vehicle yaw needs to be reset to the GPS course
|
|
ftype posDownAtLastMagReset; // vertical position last time the mag states were reset (m)
|
|
ftype yawInnovAtLastMagReset; // magnetic yaw innovation last time the yaw and mag field states were reset (rad)
|
|
QuaternionF quatAtLastMagReset; // quaternion states last time the mag states were reset
|
|
|
|
// Used by on ground movement check required when operating on ground without a yaw reference
|
|
ftype gyro_diff; // filtered gyro difference (rad/s)
|
|
ftype accel_diff; // filtered acceerometer difference (m/s/s)
|
|
Vector3F gyro_prev; // gyro vector from previous time step (rad/s)
|
|
Vector3F accel_prev; // accelerometer vector from previous time step (m/s/s)
|
|
bool onGroundNotMoving; // true when on the ground and not moving
|
|
uint32_t lastMoveCheckLogTime_ms; // last time the movement check data was logged (msec)
|
|
|
|
// variables used to inhibit accel bias learning
|
|
bool inhibitDelVelBiasStates; // true when all IMU delta velocity bias states are de-activated
|
|
bool dvelBiasAxisInhibit[3] {}; // true when IMU delta velocity bias states for a specific axis is de-activated
|
|
Vector3F dvelBiasAxisVarPrev; // saved delta velocity XYZ bias variances (m/sec)**2
|
|
|
|
#if EK3_FEATURE_EXTERNAL_NAV
|
|
// external navigation fusion
|
|
EKF_obs_buffer_t<ext_nav_elements> storedExtNav; // external navigation data buffer
|
|
ext_nav_elements extNavDataDelayed; // External nav at the fusion time horizon
|
|
uint32_t extNavMeasTime_ms; // time external measurements were accepted for input to the data buffer (msec)
|
|
uint32_t extNavLastPosResetTime_ms; // last time the external nav systen performed a position reset (msec)
|
|
bool extNavDataToFuse; // true when there is new external nav data to fuse
|
|
bool extNavUsedForPos; // true when the external nav data is being used as a position reference.
|
|
EKF_obs_buffer_t<ext_nav_vel_elements> storedExtNavVel; // external navigation velocity data buffer
|
|
ext_nav_vel_elements extNavVelDelayed; // external navigation velocity data at the fusion time horizon. Already corrected for sensor position
|
|
uint32_t extNavVelMeasTime_ms; // time external navigation velocity measurements were accepted for input to the data buffer (msec)
|
|
bool extNavVelToFuse; // true when there is new external navigation velocity to fuse
|
|
Vector3F extNavVelInnov; // external nav velocity innovations
|
|
Vector3F extNavVelVarInnov; // external nav velocity innovation variances
|
|
uint32_t extNavVelInnovTime_ms; // system time that external nav velocity innovations were recorded (to detect timeouts)
|
|
EKF_obs_buffer_t<yaw_elements> storedExtNavYawAng; // external navigation yaw angle buffer
|
|
yaw_elements extNavYawAngDataDelayed; // external navigation yaw angle at the fusion time horizon
|
|
uint32_t last_extnav_yaw_fusion_ms; // system time that external nav yaw was last fused
|
|
#endif // EK3_FEATURE_EXTERNAL_NAV
|
|
bool useExtNavVel; // true if external nav velocity should be used
|
|
|
|
// flags indicating severe numerical errors in innovation variance calculation for different fusion operations
|
|
struct {
|
|
bool bad_xmag:1;
|
|
bool bad_ymag:1;
|
|
bool bad_zmag:1;
|
|
bool bad_airspeed:1;
|
|
bool bad_sideslip:1;
|
|
bool bad_nvel:1;
|
|
bool bad_evel:1;
|
|
bool bad_dvel:1;
|
|
bool bad_npos:1;
|
|
bool bad_epos:1;
|
|
bool bad_dpos:1;
|
|
bool bad_yaw:1;
|
|
bool bad_decl:1;
|
|
bool bad_xflow:1;
|
|
bool bad_yflow:1;
|
|
bool bad_rngbcn:1;
|
|
bool bad_xvel:1;
|
|
bool bad_yvel:1;
|
|
bool bad_zvel:1;
|
|
} faultStatus;
|
|
|
|
// flags indicating which GPS quality checks are failing
|
|
union {
|
|
struct {
|
|
bool bad_sAcc:1;
|
|
bool bad_hAcc:1;
|
|
bool bad_vAcc:1;
|
|
bool bad_yaw:1;
|
|
bool bad_sats:1;
|
|
bool bad_VZ:1;
|
|
bool bad_horiz_drift:1;
|
|
bool bad_hdop:1;
|
|
bool bad_vert_vel:1;
|
|
bool bad_fix:1;
|
|
bool bad_horiz_vel:1;
|
|
};
|
|
uint16_t value;
|
|
} gpsCheckStatus;
|
|
|
|
// states held by magnetometer fusion across time steps
|
|
// magnetometer X,Y,Z measurements are fused across three time steps
|
|
// to level computational load as this is an expensive operation
|
|
struct {
|
|
ftype q0;
|
|
ftype q1;
|
|
ftype q2;
|
|
ftype q3;
|
|
ftype magN;
|
|
ftype magE;
|
|
ftype magD;
|
|
ftype magXbias;
|
|
ftype magYbias;
|
|
ftype magZbias;
|
|
Matrix3F DCM;
|
|
Vector3F MagPred;
|
|
ftype R_MAG;
|
|
Vector9 SH_MAG;
|
|
} mag_state;
|
|
|
|
// string representing last reason for prearm failure
|
|
char prearm_fail_string[40];
|
|
|
|
// earth field from WMM tables
|
|
bool have_table_earth_field; // true when we have initialised table_earth_field_ga
|
|
Vector3F table_earth_field_ga; // earth field from WMM tables
|
|
ftype table_declination; // declination in radians from the tables
|
|
|
|
// 1Hz update
|
|
uint32_t last_oneHz_ms;
|
|
void oneHzUpdate(void);
|
|
|
|
// move EKF origin at 1Hz
|
|
void moveEKFOrigin(void);
|
|
|
|
// handle earth field updates
|
|
void getEarthFieldTable(const Location &loc);
|
|
void checkUpdateEarthField(void);
|
|
|
|
// timing statistics
|
|
struct ekf_timing timing;
|
|
|
|
// when was attitude filter status last non-zero?
|
|
uint32_t last_filter_ok_ms;
|
|
|
|
// should we assume zero sideslip?
|
|
bool assume_zero_sideslip(void) const;
|
|
|
|
// vehicle specific initial gyro bias uncertainty
|
|
ftype InitialGyroBiasUncertainty(void) const;
|
|
|
|
/*
|
|
learn magnetometer biases from GPS yaw. Return true if the
|
|
resulting mag vector is close enough to the one predicted by GPS
|
|
yaw to use it for fallback
|
|
*/
|
|
bool learnMagBiasFromGPS(void);
|
|
|
|
uint32_t last_gps_yaw_ms; // last time the EKF attempted to use the GPS yaw
|
|
uint32_t last_gps_yaw_fuse_ms; // last time the EKF successfully fused the GPS yaw
|
|
bool gps_yaw_mag_fallback_ok;
|
|
bool gps_yaw_mag_fallback_active;
|
|
uint8_t gps_yaw_fallback_good_counter;
|
|
|
|
/*
|
|
Update the on ground and not moving check.
|
|
Should be called once per IMU update.
|
|
Only updates when on ground and when operating with an external yaw sensor
|
|
*/
|
|
void updateMovementCheck(void);
|
|
|
|
// The following declarations are used to control when the main navigation filter resets it's yaw to the estimate provided by the GSF
|
|
uint32_t EKFGSF_yaw_reset_ms; // timestamp of last emergency yaw reset (uSec)
|
|
uint32_t EKFGSF_yaw_reset_request_ms; // timestamp of last emergency yaw reset request (uSec)
|
|
uint8_t EKFGSF_yaw_reset_count; // number of emergency yaw resets performed
|
|
bool EKFGSF_run_filterbank; // true when the filter bank is active
|
|
uint8_t EKFGSF_yaw_valid_count; // number of updates since the last invalid yaw estimate
|
|
|
|
// logging timestamps
|
|
uint32_t lastLogTime_ms;
|
|
uint32_t lastUpdateTime_ms;
|
|
uint32_t lastEkfStateVarLogTime_ms;
|
|
uint32_t lastTimingLogTime_ms;
|
|
|
|
// bits in EK3_AFFINITY
|
|
enum ekf_affinity {
|
|
EKF_AFFINITY_GPS = (1U<<0),
|
|
EKF_AFFINITY_BARO = (1U<<1),
|
|
EKF_AFFINITY_MAG = (1U<<2),
|
|
EKF_AFFINITY_ARSP = (1U<<3),
|
|
};
|
|
|
|
// update selected_sensors for this core
|
|
void update_sensor_selection(void);
|
|
void update_gps_selection(void);
|
|
void update_mag_selection(void);
|
|
void update_baro_selection(void);
|
|
void update_airspeed_selection(void);
|
|
|
|
// selected and preferred sensor instances. We separate selected
|
|
// from preferred so that calcGpsGoodToAlign() can ensure the
|
|
// preferred sensor is ready. Note that magSelectIndex is used for
|
|
// compass selection
|
|
uint8_t selected_gps;
|
|
uint8_t preferred_gps;
|
|
uint8_t selected_baro;
|
|
uint8_t selected_airspeed;
|
|
|
|
// source reset handling
|
|
AP_NavEKF_Source::SourceXY posxy_source_last; // horizontal position source on previous iteration (used to detect a changes)
|
|
bool posxy_source_reset; // true when the horizontal position source has changed but the position has not yet been reset
|
|
AP_NavEKF_Source::SourceYaw yaw_source_last; // yaw source on previous iteration (used to detect a change)
|
|
bool yaw_source_reset; // true when the yaw source has changed but the yaw has not yet been reset
|
|
|
|
// logging functions shared by cores:
|
|
void Log_Write_XKF1(uint64_t time_us) const;
|
|
void Log_Write_XKF2(uint64_t time_us) const;
|
|
void Log_Write_XKF3(uint64_t time_us) const;
|
|
void Log_Write_XKF4(uint64_t time_us) const;
|
|
void Log_Write_XKF5(uint64_t time_us) const;
|
|
void Log_Write_XKFS(uint64_t time_us) const;
|
|
void Log_Write_Quaternion(uint64_t time_us) const;
|
|
void Log_Write_Beacon(uint64_t time_us);
|
|
void Log_Write_BodyOdom(uint64_t time_us);
|
|
void Log_Write_State_Variances(uint64_t time_us);
|
|
void Log_Write_Timing(uint64_t time_us);
|
|
void Log_Write_GSF(uint64_t time_us);
|
|
};
|