mirror of https://github.com/ArduPilot/ardupilot
569 lines
26 KiB
C++
569 lines
26 KiB
C++
#include <AP_HAL/AP_HAL.h>
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#include "AP_NavEKF2.h"
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#include "AP_NavEKF2_core.h"
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#include <GCS_MAVLink/GCS.h>
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extern const AP_HAL::HAL& hal;
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// Control filter mode transitions
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void NavEKF2_core::controlFilterModes()
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{
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// Determine motor arm status
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prevMotorsArmed = motorsArmed;
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motorsArmed = dal.get_armed();
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if (motorsArmed && !prevMotorsArmed) {
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// set the time at which we arm to assist with checks
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timeAtArming_ms = imuSampleTime_ms;
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}
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// Detect if we are in flight on or ground
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detectFlight();
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// Determine if learning of wind and magnetic field will be enabled and set corresponding indexing limits to
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// avoid unnecessary operations
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setWindMagStateLearningMode();
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// Check the alignmnent status of the tilt and yaw attitude
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// Used during initial bootstrap alignment of the filter
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checkAttitudeAlignmentStatus();
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// Set the type of inertial navigation aiding used
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setAidingMode();
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}
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/*
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return effective value for _magCal for this core
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*/
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uint8_t NavEKF2_core::effective_magCal(void) const
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{
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// force use of simple magnetic heading fusion for specified cores
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if (frontend->_magMask & core_index) {
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return 2;
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} else {
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return frontend->_magCal;
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}
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}
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// Determine if learning of wind and magnetic field will be enabled and set corresponding indexing limits to
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// avoid unnecessary operations
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void NavEKF2_core::setWindMagStateLearningMode()
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{
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// If we are on ground, or in constant position mode, or don't have the right vehicle and sensing to estimate wind, inhibit wind states
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bool setWindInhibit = (!useAirspeed() && !assume_zero_sideslip()) || onGround || (PV_AidingMode == AID_NONE);
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if (!inhibitWindStates && setWindInhibit) {
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inhibitWindStates = true;
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} else if (inhibitWindStates && !setWindInhibit) {
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inhibitWindStates = false;
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// set states and variances
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if (yawAlignComplete && useAirspeed()) {
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// if we have airspeed and a valid heading, set the wind states to the reciprocal of the vehicle heading
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// which assumes the vehicle has launched into the wind
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Vector3F tempEuler;
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stateStruct.quat.to_euler(tempEuler.x, tempEuler.y, tempEuler.z);
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ftype windSpeed = sqrtF(sq(stateStruct.velocity.x) + sq(stateStruct.velocity.y)) - tasDataDelayed.tas;
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stateStruct.wind_vel.x = windSpeed * cosF(tempEuler.z);
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stateStruct.wind_vel.y = windSpeed * sinF(tempEuler.z);
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// set the wind sate variances to the measurement uncertainty
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for (uint8_t index=22; index<=23; index++) {
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P[index][index] = sq(constrain_ftype(frontend->_easNoise, 0.5f, 5.0f) * constrain_ftype(dal.get_EAS2TAS(), 0.9f, 10.0f));
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}
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} else {
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// set the variances using a typical wind speed
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for (uint8_t index=22; index<=23; index++) {
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P[index][index] = sq(5.0f);
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}
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}
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}
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// determine if the vehicle is manoeuvring
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if (accNavMagHoriz > 0.5f) {
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manoeuvring = true;
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} else {
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manoeuvring = false;
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}
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// Determine if learning of magnetic field states has been requested by the user
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uint8_t magCal = effective_magCal();
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bool magCalRequested =
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((magCal == 0) && inFlight) || // when flying
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((magCal == 1) && manoeuvring) || // when manoeuvring
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((magCal == 3) && finalInflightYawInit && finalInflightMagInit) || // when initial in-air yaw and mag field reset is complete
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(magCal == 4); // all the time
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// Deny mag calibration request if we aren't using the compass, it has been inhibited by the user,
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// we do not have an absolute position reference or are on the ground (unless explicitly requested by the user)
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bool magCalDenied = !use_compass() || (magCal == 2) || (onGround && magCal != 4);
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// Inhibit the magnetic field calibration if not requested or denied
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bool setMagInhibit = !magCalRequested || magCalDenied;
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if (!inhibitMagStates && setMagInhibit) {
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inhibitMagStates = true;
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// variances will be reset in CovariancePrediction
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} else if (inhibitMagStates && !setMagInhibit) {
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inhibitMagStates = false;
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if (magFieldLearned) {
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// if we have already learned the field states, then retain the learned variances
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P[16][16] = earthMagFieldVar.x;
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P[17][17] = earthMagFieldVar.y;
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P[18][18] = earthMagFieldVar.z;
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P[19][19] = bodyMagFieldVar.x;
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P[20][20] = bodyMagFieldVar.y;
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P[21][21] = bodyMagFieldVar.z;
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} else {
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// set the variances equal to the observation variances
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for (uint8_t index=16; index<=21; index++) {
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P[index][index] = sq(frontend->_magNoise);
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}
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// set the NE earth magnetic field states using the published declination
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// and set the corresponding variances and covariances
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alignMagStateDeclination();
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}
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// request a reset of the yaw and magnetic field states if not done before
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if (!magStateInitComplete || (!finalInflightMagInit && inFlight)) {
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magYawResetRequest = true;
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}
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}
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// If on ground we clear the flag indicating that the magnetic field in-flight initialisation has been completed
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// because we want it re-done for each takeoff
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if (onGround) {
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finalInflightYawInit = false;
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finalInflightMagInit = false;
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}
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// Adjust the indexing limits used to address the covariance, states and other EKF arrays to avoid unnecessary operations
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// if we are not using those states
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if (inhibitMagStates && inhibitWindStates) {
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stateIndexLim = 15;
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} else if (inhibitWindStates) {
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stateIndexLim = 21;
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} else {
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stateIndexLim = 23;
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}
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}
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// Set inertial navigation aiding mode
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void NavEKF2_core::setAidingMode()
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{
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// Save the previous status so we can detect when it has changed
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PV_AidingModePrev = PV_AidingMode;
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// Determine if we should change aiding mode
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switch (PV_AidingMode) {
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case AID_NONE: {
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// Don't allow filter to start position or velocity aiding until the tilt and yaw alignment is complete
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// and IMU gyro bias estimates have stabilised
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bool filterIsStable = tiltAlignComplete && yawAlignComplete && checkGyroCalStatus();
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// If GPS usage has been prohiited then we use flow aiding provided optical flow data is present
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// GPS aiding is the preferred option unless excluded by the user
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bool canUseGPS = ((frontend->_fusionModeGPS) != 3 && readyToUseGPS() && filterIsStable);
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bool canUseRangeBeacon = readyToUseRangeBeacon() && filterIsStable;
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bool canUseExtNav = readyToUseExtNav();
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if(canUseGPS || canUseRangeBeacon || canUseExtNav) {
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PV_AidingMode = AID_ABSOLUTE;
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} else if (optFlowDataPresent() && (frontend->_flowUse == FLOW_USE_NAV) && filterIsStable) {
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PV_AidingMode = AID_RELATIVE;
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}
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}
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break;
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case AID_RELATIVE: {
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// Check if the optical flow sensor has timed out
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bool flowSensorTimeout = ((imuSampleTime_ms - flowValidMeaTime_ms) > 5000);
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// Check if the fusion has timed out (flow measurements have been rejected for too long)
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bool flowFusionTimeout = ((imuSampleTime_ms - prevFlowFuseTime_ms) > 5000);
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// Enable switch to absolute position mode if GPS is available
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// If GPS is not available and flow fusion has timed out, then fall-back to no-aiding
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if((frontend->_fusionModeGPS) != 3 && readyToUseGPS()) {
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PV_AidingMode = AID_ABSOLUTE;
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} else if (flowSensorTimeout || flowFusionTimeout) {
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PV_AidingMode = AID_NONE;
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}
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}
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break;
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case AID_ABSOLUTE: {
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// Find the minimum time without data required to trigger any check
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uint16_t minTestTime_ms = MIN(frontend->tiltDriftTimeMax_ms, MIN(frontend->posRetryTimeNoVel_ms,frontend->posRetryTimeUseVel_ms));
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// Check if optical flow data is being used
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bool optFlowUsed = (imuSampleTime_ms - prevFlowFuseTime_ms <= minTestTime_ms);
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// Check if airspeed data is being used
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bool airSpdUsed = (imuSampleTime_ms - lastTasPassTime_ms <= minTestTime_ms);
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// Check if range beacon data is being used
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bool rngBcnUsed = (imuSampleTime_ms - lastRngBcnPassTime_ms <= minTestTime_ms);
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// Check if GPS is being used
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bool posUsed = (imuSampleTime_ms - lastPosPassTime_ms <= minTestTime_ms);
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bool gpsVelUsed = (imuSampleTime_ms - lastVelPassTime_ms <= minTestTime_ms);
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// Check if external nav is being used
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bool extNavUsed = (imuSampleTime_ms - lastExtNavPassTime_ms <= minTestTime_ms);
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// Check if attitude drift has been constrained by a measurement source
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bool attAiding = posUsed || gpsVelUsed || optFlowUsed || airSpdUsed || rngBcnUsed || extNavUsed;
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// check if velocity drift has been constrained by a measurement source
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bool velAiding = gpsVelUsed || airSpdUsed || optFlowUsed;
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// check if position drift has been constrained by a measurement source
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bool posAiding = posUsed || rngBcnUsed || extNavUsed;
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// Check if the loss of attitude aiding has become critical
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bool attAidLossCritical = false;
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if (!attAiding) {
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attAidLossCritical = (imuSampleTime_ms - prevFlowFuseTime_ms > frontend->tiltDriftTimeMax_ms) &&
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(imuSampleTime_ms - lastTasPassTime_ms > frontend->tiltDriftTimeMax_ms) &&
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(imuSampleTime_ms - lastRngBcnPassTime_ms > frontend->tiltDriftTimeMax_ms) &&
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(imuSampleTime_ms - lastPosPassTime_ms > frontend->tiltDriftTimeMax_ms) &&
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(imuSampleTime_ms - lastExtNavPassTime_ms > frontend->tiltDriftTimeMax_ms) &&
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(imuSampleTime_ms - lastVelPassTime_ms > frontend->tiltDriftTimeMax_ms);
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}
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// Check if the loss of position accuracy has become critical
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bool posAidLossCritical = false;
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if (!posAiding ) {
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uint16_t maxLossTime_ms;
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if (!velAiding) {
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maxLossTime_ms = frontend->posRetryTimeNoVel_ms;
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} else {
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maxLossTime_ms = frontend->posRetryTimeUseVel_ms;
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}
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posAidLossCritical = (imuSampleTime_ms - lastRngBcnPassTime_ms > maxLossTime_ms) &&
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(imuSampleTime_ms - lastExtNavPassTime_ms > maxLossTime_ms) &&
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(imuSampleTime_ms - lastPosPassTime_ms > maxLossTime_ms);
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}
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if (attAidLossCritical) {
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// if the loss of attitude data is critical, then put the filter into a constant position mode
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PV_AidingMode = AID_NONE;
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posTimeout = true;
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velTimeout = true;
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rngBcnTimeout = true;
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tasTimeout = true;
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gpsNotAvailable = true;
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} else if (posAidLossCritical) {
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if ((frontend->_flowUse == FLOW_USE_NAV) && optFlowDataPresent() && (imuSampleTime_ms - rngValidMeaTime_ms < 500)) {
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PV_AidingMode = AID_NONE;
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}
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// if the loss of position is critical, declare all sources of position aiding as being timed out
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posTimeout = true;
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velTimeout = true;
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rngBcnTimeout = true;
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gpsNotAvailable = true;
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}
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break;
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}
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}
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// check to see if we are starting or stopping aiding and set states and modes as required
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if (PV_AidingMode != PV_AidingModePrev) {
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// set various usage modes based on the condition when we start aiding. These are then held until aiding is stopped.
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switch (PV_AidingMode) {
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case AID_NONE:
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// We have ceased aiding
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GCS_SEND_TEXT(MAV_SEVERITY_WARNING, "EKF2 IMU%u has stopped aiding",(unsigned)imu_index);
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// When not aiding, estimate orientation & height fusing synthetic constant position and zero velocity measurement to constrain tilt errors
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posTimeout = true;
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velTimeout = true;
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// Reset the normalised innovation to avoid false failing bad fusion tests
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velTestRatio = 0.0f;
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posTestRatio = 0.0f;
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// store the current position to be used to keep reporting the last known position
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lastKnownPositionNE.x = stateStruct.position.x;
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lastKnownPositionNE.y = stateStruct.position.y;
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// initialise filtered altitude used to provide a takeoff reference to current baro on disarm
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// this reduces the time required for the baro noise filter to settle before the filtered baro data can be used
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meaHgtAtTakeOff = baroDataDelayed.hgt;
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// reset the vertical position state to faster recover from baro errors experienced during touchdown
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stateStruct.position.z = -meaHgtAtTakeOff;
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break;
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case AID_RELATIVE:
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// We have commenced aiding, but GPS usage has been prohibited so use optical flow only
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u is using optical flow",(unsigned)imu_index);
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posTimeout = true;
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velTimeout = true;
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// Reset the last valid flow measurement time
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flowValidMeaTime_ms = imuSampleTime_ms;
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// Reset the last valid flow fusion time
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prevFlowFuseTime_ms = imuSampleTime_ms;
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break;
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case AID_ABSOLUTE: {
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bool canUseGPS = ((frontend->_fusionModeGPS) != 3 && readyToUseGPS());
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bool canUseRangeBeacon = readyToUseRangeBeacon();
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bool canUseExtNav = readyToUseExtNav();
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// We have commenced aiding and GPS usage is allowed
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if (canUseGPS) {
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u is using GPS",(unsigned)imu_index);
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}
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posTimeout = false;
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velTimeout = false;
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// We have commenced aiding and range beacon usage is allowed
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if (canUseRangeBeacon) {
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u is using range beacons",(unsigned)imu_index);
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u initial pos NE = %3.1f,%3.1f (m)",(unsigned)imu_index,(double)receiverPos.x,(double)receiverPos.y);
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u initial beacon pos D offset = %3.1f (m)",(unsigned)imu_index,(double)bcnPosOffset);
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}
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// We have commenced aiding and external nav usage is allowed
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if (canUseExtNav) {
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u is using external nav data",(unsigned)imu_index);
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u initial pos NED = %3.1f,%3.1f,%3.1f (m)",(unsigned)imu_index,(double)extNavDataDelayed.pos.x,(double)extNavDataDelayed.pos.y,(double)extNavDataDelayed.pos.z);
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//handle yaw reset as special case only if compass is disabled
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if (!use_compass()) {
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extNavYawResetRequest = true;
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controlMagYawReset();
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}
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// handle height reset as special case
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hgtMea = -extNavDataDelayed.pos.z;
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posDownObsNoise = sq(constrain_ftype(extNavDataDelayed.posErr, 0.1f, 10.0f));
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ResetHeight();
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}
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// reset the last fusion accepted times to prevent unwanted activation of timeout logic
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lastPosPassTime_ms = imuSampleTime_ms;
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lastVelPassTime_ms = imuSampleTime_ms;
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lastRngBcnPassTime_ms = imuSampleTime_ms;
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lastExtNavPassTime_ms = imuSampleTime_ms;
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}
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break;
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}
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// Always reset the position and velocity when changing mode
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ResetVelocity();
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ResetPosition();
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}
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}
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// Check the tilt and yaw alignmnent status
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// Used during initial bootstrap alignment of the filter
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void NavEKF2_core::checkAttitudeAlignmentStatus()
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{
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// Check for tilt convergence - used during initial alignment
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ftype alpha = 1.0f*imuDataDelayed.delAngDT;
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ftype temp=tiltErrVec.length();
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tiltErrFilt = alpha*temp + (1.0f-alpha)*tiltErrFilt;
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if (tiltErrFilt < 0.005f && !tiltAlignComplete) {
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tiltAlignComplete = true;
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u tilt alignment complete",(unsigned)imu_index);
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}
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// submit yaw and magnetic field reset requests depending on whether we have compass data
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if (tiltAlignComplete && !yawAlignComplete) {
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if (use_compass()) {
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magYawResetRequest = true;
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gpsYawResetRequest = false;
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} else {
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magYawResetRequest = false;
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gpsYawResetRequest = true;
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}
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}
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}
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// return true if we should use the airspeed sensor
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bool NavEKF2_core::useAirspeed(void) const
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{
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return dal.airspeed_sensor_enabled();
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}
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// return true if we should use the range finder sensor
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bool NavEKF2_core::useRngFinder(void) const
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{
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// TO-DO add code to set this based in setting of optical flow use parameter and presence of sensor
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return true;
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}
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// return true if optical flow data is available
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bool NavEKF2_core::optFlowDataPresent(void) const
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{
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return (imuSampleTime_ms - flowMeaTime_ms < 200);
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}
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// return true if the filter to be ready to use gps
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bool NavEKF2_core::readyToUseGPS(void) const
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{
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return validOrigin && tiltAlignComplete && yawAlignComplete && gpsGoodToAlign && (frontend->_fusionModeGPS != 3) && gpsDataToFuse;
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}
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// return true if the filter to be ready to use the beacon range measurements
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bool NavEKF2_core::readyToUseRangeBeacon(void) const
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{
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return tiltAlignComplete && yawAlignComplete && rngBcnGoodToAlign && rngBcnDataToFuse;
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}
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// return true if the filter to be ready to use external nav data
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bool NavEKF2_core::readyToUseExtNav(void) const
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{
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return tiltAlignComplete && extNavDataToFuse;
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}
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// return true if we should use the compass
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bool NavEKF2_core::use_compass(void) const
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{
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return dal.compass().use_for_yaw(magSelectIndex) && !allMagSensorsFailed;
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}
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/*
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should we assume zero sideslip?
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*/
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bool NavEKF2_core::assume_zero_sideslip(void) const
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{
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// we don't assume zero sideslip for ground vehicles as EKF could
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// be quite sensitive to a rapid spin of the ground vehicle if
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// traction is lost
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return dal.get_fly_forward() && dal.get_vehicle_class() != AP_DAL::VehicleClass::GROUND;
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}
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// sets the local NED origin using a LLH location (latitude, longitude, height)
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// returns false if absolute aiding and GPS is being used or if the origin is already set
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bool NavEKF2_core::setOriginLLH(const Location &loc)
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{
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if (PV_AidingMode == AID_ABSOLUTE && !extNavUsedForPos) {
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// reject attempts to set the origin if GPS is being used
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return false;
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}
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return setOrigin(loc);
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}
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// sets the local NED origin using a LLH location (latitude, longitude, height)
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// returns false if the origin has already been set
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bool NavEKF2_core::setOrigin(const Location &loc)
|
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{
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// if the origin is valid reject setting a new origin
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if (validOrigin) {
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return false;
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}
|
|
|
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EKF_origin = loc;
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ekfGpsRefHgt = (double)0.01 * (double)EKF_origin.alt;
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// define Earth rotation vector in the NED navigation frame at the origin
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calcEarthRateNED(earthRateNED, EKF_origin.lat);
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validOrigin = true;
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GCS_SEND_TEXT(MAV_SEVERITY_INFO, "EKF2 IMU%u origin set",(unsigned)imu_index);
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|
|
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// put origin in frontend as well to ensure it stays in sync between lanes
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frontend->common_EKF_origin = EKF_origin;
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frontend->common_origin_valid = true;
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|
|
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return true;
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}
|
|
|
|
// record a yaw reset event
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void NavEKF2_core::recordYawReset()
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|
{
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|
yawAlignComplete = true;
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|
if (inFlight) {
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|
finalInflightYawInit = true;
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|
}
|
|
}
|
|
|
|
// return true and set the class variable true if the delta angle bias has been learned
|
|
bool NavEKF2_core::checkGyroCalStatus(void)
|
|
{
|
|
// check delta angle bias variances
|
|
const ftype delAngBiasVarMax = sq(radians(0.15f * dtEkfAvg));
|
|
if (!use_compass()) {
|
|
// rotate the variances into earth frame and evaluate horizontal terms only as yaw component is poorly observable without a compass
|
|
// which can make this check fail
|
|
Vector3F delAngBiasVarVec = Vector3F(P[9][9],P[10][10],P[11][11]);
|
|
Vector3F temp = prevTnb * delAngBiasVarVec;
|
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delAngBiasLearned = (fabsF(temp.x) < delAngBiasVarMax) &&
|
|
(fabsF(temp.y) < delAngBiasVarMax);
|
|
} else {
|
|
delAngBiasLearned = (P[9][9] <= delAngBiasVarMax) &&
|
|
(P[10][10] <= delAngBiasVarMax) &&
|
|
(P[11][11] <= delAngBiasVarMax);
|
|
}
|
|
return delAngBiasLearned;
|
|
}
|
|
|
|
// Update the filter status
|
|
void NavEKF2_core::updateFilterStatus(void)
|
|
{
|
|
// init return value
|
|
filterStatus.value = 0;
|
|
bool doingFlowNav = (PV_AidingMode == AID_RELATIVE) && flowDataValid;
|
|
bool doingWindRelNav = !tasTimeout && assume_zero_sideslip();
|
|
bool doingNormalGpsNav = !posTimeout && (PV_AidingMode == AID_ABSOLUTE);
|
|
bool someVertRefData = (!velTimeout && (useGpsVertVel || useExtNavVel)) || !hgtTimeout;
|
|
bool someHorizRefData = !(velTimeout && posTimeout && tasTimeout) || doingFlowNav;
|
|
bool optFlowNavPossible = flowDataValid && delAngBiasLearned;
|
|
bool gpsNavPossible = !gpsNotAvailable && gpsGoodToAlign && delAngBiasLearned;
|
|
bool filterHealthy = healthy() && tiltAlignComplete && (yawAlignComplete || (!use_compass() && (PV_AidingMode == AID_NONE)));
|
|
// If GPS height usage is specified, height is considered to be inaccurate until the GPS passes all checks
|
|
bool hgtNotAccurate = (frontend->_altSource == 2) && !validOrigin;
|
|
|
|
// set individual flags
|
|
filterStatus.flags.attitude = !stateStruct.quat.is_nan() && filterHealthy; // attitude valid (we need a better check)
|
|
filterStatus.flags.horiz_vel = someHorizRefData && filterHealthy; // horizontal velocity estimate valid
|
|
filterStatus.flags.vert_vel = someVertRefData && filterHealthy; // vertical velocity estimate valid
|
|
filterStatus.flags.horiz_pos_rel = ((doingFlowNav && gndOffsetValid) || doingWindRelNav || doingNormalGpsNav) && filterHealthy; // relative horizontal position estimate valid
|
|
filterStatus.flags.horiz_pos_abs = doingNormalGpsNav && filterHealthy; // absolute horizontal position estimate valid
|
|
filterStatus.flags.vert_pos = !hgtTimeout && filterHealthy && !hgtNotAccurate; // vertical position estimate valid
|
|
filterStatus.flags.terrain_alt = gndOffsetValid && filterHealthy; // terrain height estimate valid
|
|
filterStatus.flags.const_pos_mode = (PV_AidingMode == AID_NONE) && filterHealthy; // constant position mode
|
|
filterStatus.flags.pred_horiz_pos_rel = ((optFlowNavPossible || gpsNavPossible) && filterHealthy) || filterStatus.flags.horiz_pos_rel; // we should be able to estimate a relative position when we enter flight mode
|
|
filterStatus.flags.pred_horiz_pos_abs = (gpsNavPossible && filterHealthy) || filterStatus.flags.horiz_pos_abs; // we should be able to estimate an absolute position when we enter flight mode
|
|
filterStatus.flags.takeoff_detected = takeOffDetected; // takeoff for optical flow navigation has been detected
|
|
filterStatus.flags.takeoff = dal.get_takeoff_expected(); // The EKF has been told to expect takeoff and is in a ground effect mitigation mode
|
|
filterStatus.flags.touchdown = dal.get_touchdown_expected(); // The EKF has been told to detect touchdown and is in a ground effect mitigation mode
|
|
filterStatus.flags.using_gps = ((imuSampleTime_ms - lastPosPassTime_ms) < 4000) && (PV_AidingMode == AID_ABSOLUTE);
|
|
filterStatus.flags.gps_glitching = !gpsAccuracyGood && (PV_AidingMode == AID_ABSOLUTE) && !extNavUsedForPos; // GPS glitching is affecting navigation accuracy
|
|
filterStatus.flags.gps_quality_good = gpsGoodToAlign;
|
|
// for reporting purposes we report rejecting airspeed after 3s of not fusing when we want to fuse the data
|
|
filterStatus.flags.rejecting_airspeed = lastTasFailTime_ms != 0 &&
|
|
(imuSampleTime_ms - lastTasFailTime_ms) < 1000 &&
|
|
(imuSampleTime_ms - lastTasPassTime_ms) > 3000;
|
|
filterStatus.flags.initalized = filterStatus.flags.initalized || healthy();
|
|
}
|
|
|
|
void NavEKF2_core::runYawEstimatorPrediction()
|
|
{
|
|
if (yawEstimator != nullptr && frontend->_fusionModeGPS <= 1) {
|
|
ftype trueAirspeed;
|
|
if (is_positive(defaultAirSpeed) && assume_zero_sideslip()) {
|
|
if (imuDataDelayed.time_ms - tasDataDelayed.time_ms < 5000) {
|
|
trueAirspeed = tasDataDelayed.tas;
|
|
} else {
|
|
trueAirspeed = defaultAirSpeed * dal.get_EAS2TAS();
|
|
}
|
|
} else {
|
|
trueAirspeed = 0.0f;
|
|
}
|
|
|
|
yawEstimator->update(imuDataDelayed.delAng, imuDataDelayed.delVel, imuDataDelayed.delAngDT, imuDataDelayed.delVelDT, EKFGSF_run_filterbank, trueAirspeed);
|
|
}
|
|
}
|
|
|
|
void NavEKF2_core::runYawEstimatorCorrection()
|
|
{
|
|
if (yawEstimator != nullptr && frontend->_fusionModeGPS <= 1 && EKFGSF_run_filterbank) {
|
|
if (gpsDataToFuse) {
|
|
Vector2F gpsVelNE = Vector2F(gpsDataDelayed.vel.x, gpsDataDelayed.vel.y);
|
|
ftype gpsVelAcc = fmaxF(gpsSpdAccuracy, ftype(frontend->_gpsHorizVelNoise));
|
|
yawEstimator->fuseVelData(gpsVelNE, gpsVelAcc);
|
|
}
|
|
|
|
// action an external reset request
|
|
if (EKFGSF_yaw_reset_request_ms > 0 && imuSampleTime_ms - EKFGSF_yaw_reset_request_ms < YAW_RESET_TO_GSF_TIMEOUT_MS) {
|
|
EKFGSF_resetMainFilterYaw();
|
|
}
|
|
}
|
|
}
|
|
|
|
// request a reset the yaw to the GSF estimate
|
|
// request times out after YAW_RESET_TO_GSF_TIMEOUT_MS if it cannot be actioned
|
|
void NavEKF2_core::EKFGSF_requestYawReset()
|
|
{
|
|
EKFGSF_yaw_reset_request_ms = imuSampleTime_ms;
|
|
}
|