/****************************************************************************
*
* Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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****************************************************************************/
/**
* @file ekf_att_pos_estimator_main.cpp
* Implementation of the attitude and position estimator.
*
* @author Paul Riseborough <p_riseborough@live.com.au>
* @author Lorenz Meier <lm@inf.ethz.ch>
* @author Johan Jansen <jnsn.johan@gmail.com>
*/
#include "AttitudePositionEstimatorEKF.h"
#include "estimator_22states.h"
#include <nuttx/config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <math.h>
#include <poll.h>
#include <time.h>
#include <float.h>
#include <arch/board/board.h>
#include <systemlib/param/param.h>
#include <systemlib/err.h>
#include <systemlib/systemlib.h>
#include <mathlib/mathlib.h>
#include <mathlib/math/filter/LowPassFilter2p.hpp>
#include <mavlink/mavlink_log.h>
#include <platforms/px4_defines.h>
static uint64_t IMUmsec = 0;
static uint64_t IMUusec = 0;
//Constants
static constexpr float rc = 10.0f; // RC time constant of 1st order LPF in seconds
static constexpr uint64_t FILTER_INIT_DELAY = 1 * 1000 * 1000; ///< units: microseconds
static constexpr float POS_RESET_THRESHOLD = 5.0f; ///< Seconds before we signal a total GPS failure
/**
* estimator app start / stop handling function
*
* @ingroup apps
*/
extern "C" __EXPORT int ekf_att_pos_estimator_main(int argc, char *argv[]);
__EXPORT uint32_t millis();
__EXPORT uint64_t getMicros();
uint32_t millis()
{
return IMUmsec;
}
uint64_t getMicros()
{
return IMUusec;
}
namespace estimator
{
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;
AttitudePositionEstimatorEKF *g_estimator = nullptr;
}
AttitudePositionEstimatorEKF::AttitudePositionEstimatorEKF() :
_task_should_exit(false),
_task_running(false),
_estimator_task(-1),
/* subscriptions */
_sensor_combined_sub(-1),
_distance_sub(-1),
_airspeed_sub(-1),
_baro_sub(-1),
_gps_sub(-1),
_vstatus_sub(-1),
_params_sub(-1),
_manual_control_sub(-1),
_mission_sub(-1),
_home_sub(-1),
_landDetectorSub(-1),
_armedSub(-1),
/* publications */
_att_pub(-1),
_global_pos_pub(-1),
_local_pos_pub(-1),
_estimator_status_pub(-1),
_wind_pub(-1),
_att({}),
_gyro({}),
_accel({}),
_mag({}),
_airspeed({}),
_baro({}),
_vstatus({}),
_global_pos({}),
_local_pos({}),
_gps({}),
_wind({}),
_distance {},
_landDetector {},
_armed {},
_gyro_offsets({}),
_accel_offsets({}),
_mag_offsets({}),
_sensor_combined {},
_pos_ref{},
_baro_ref_offset(0.0f),
_baro_gps_offset(0.0f),
/* performance counters */
_loop_perf(perf_alloc(PC_ELAPSED, "ekf_att_pos_estimator")),
_loop_intvl(perf_alloc(PC_INTERVAL, "ekf_att_pos_est_interval")),
_perf_gyro(perf_alloc(PC_INTERVAL, "ekf_att_pos_gyro_upd")),
_perf_mag(perf_alloc(PC_INTERVAL, "ekf_att_pos_mag_upd")),
_perf_gps(perf_alloc(PC_INTERVAL, "ekf_att_pos_gps_upd")),
_perf_baro(perf_alloc(PC_INTERVAL, "ekf_att_pos_baro_upd")),
_perf_airspeed(perf_alloc(PC_INTERVAL, "ekf_att_pos_aspd_upd")),
_perf_reset(perf_alloc(PC_COUNT, "ekf_att_pos_reset")),
/* states */
_gps_alt_filt(0.0f),
_baro_alt_filt(0.0f),
_covariancePredictionDt(0.0f),
_gpsIsGood(false),
_previousGPSTimestamp(0),
_baro_init(false),
_baroAltRef(0.0f),
_gps_initialized(false),
_filter_start_time(0),
_last_sensor_timestamp(0),
_last_run(0),
_distance_last_valid(0),
_gyro_valid(false),
_accel_valid(false),
_mag_valid(false),
_gyro_main(0),
_accel_main(0),
_mag_main(0),
_ekf_logging(true),
_debug(0),
_newHgtData(false),
_newAdsData(false),
_newDataMag(false),
_newRangeData(false),
_mavlink_fd(-1),
_parameters {},
_parameter_handles {},
_ekf(nullptr)
{
_last_run = hrt_absolute_time();
_parameter_handles.vel_delay_ms = param_find("PE_VEL_DELAY_MS");
_parameter_handles.pos_delay_ms = param_find("PE_POS_DELAY_MS");
_parameter_handles.height_delay_ms = param_find("PE_HGT_DELAY_MS");
_parameter_handles.mag_delay_ms = param_find("PE_MAG_DELAY_MS");
_parameter_handles.tas_delay_ms = param_find("PE_TAS_DELAY_MS");
_parameter_handles.velne_noise = param_find("PE_VELNE_NOISE");
_parameter_handles.veld_noise = param_find("PE_VELD_NOISE");
_parameter_handles.posne_noise = param_find("PE_POSNE_NOISE");
_parameter_handles.posd_noise = param_find("PE_POSD_NOISE");
_parameter_handles.mag_noise = param_find("PE_MAG_NOISE");
_parameter_handles.gyro_pnoise = param_find("PE_GYRO_PNOISE");
_parameter_handles.acc_pnoise = param_find("PE_ACC_PNOISE");
_parameter_handles.gbias_pnoise = param_find("PE_GBIAS_PNOISE");
_parameter_handles.abias_pnoise = param_find("PE_ABIAS_PNOISE");
_parameter_handles.mage_pnoise = param_find("PE_MAGE_PNOISE");
_parameter_handles.magb_pnoise = param_find("PE_MAGB_PNOISE");
_parameter_handles.eas_noise = param_find("PE_EAS_NOISE");
_parameter_handles.pos_stddev_threshold = param_find("PE_POSDEV_INIT");
/* fetch initial parameter values */
parameters_update();
/* get offsets */
int fd, res;
for (unsigned s = 0; s < 3; s++) {
char str[30];
(void)sprintf(str, "%s%u", GYRO_BASE_DEVICE_PATH, s);
fd = open(str, O_RDONLY);
if (fd >= 0) {
res = ioctl(fd, GYROIOCGSCALE, (long unsigned int)&_gyro_offsets[s]);
close(fd);
if (res) {
warnx("G%u SCALE FAIL", s);
}
}
(void)sprintf(str, "%s%u", ACCEL_BASE_DEVICE_PATH, s);
fd = open(str, O_RDONLY);
if (fd >= 0) {
res = ioctl(fd, ACCELIOCGSCALE, (long unsigned int)&_accel_offsets[s]);
close(fd);
if (res) {
warnx("A%u SCALE FAIL", s);
}
}
(void)sprintf(str, "%s%u", MAG_BASE_DEVICE_PATH, s);
fd = open(str, O_RDONLY);
if (fd >= 0) {
res = ioctl(fd, MAGIOCGSCALE, (long unsigned int)&_mag_offsets[s]);
close(fd);
if (res) {
warnx("M%u SCALE FAIL", s);
}
}
}
}
AttitudePositionEstimatorEKF::~AttitudePositionEstimatorEKF()
{
if (_estimator_task != -1) {
/* task wakes up every 100ms or so at the longest */
_task_should_exit = true;
/* wait for a second for the task to quit at our request */
unsigned i = 0;
do {
/* wait 20ms */
usleep(20000);
/* if we have given up, kill it */
if (++i > 50) {
task_delete(_estimator_task);
break;
}
} while (_estimator_task != -1);
}
delete _ekf;
estimator::g_estimator = nullptr;
}
int AttitudePositionEstimatorEKF::enable_logging(bool logging)
{
_ekf_logging = logging;
return 0;
}
int AttitudePositionEstimatorEKF::parameters_update()
{
param_get(_parameter_handles.vel_delay_ms, &(_parameters.vel_delay_ms));
param_get(_parameter_handles.pos_delay_ms, &(_parameters.pos_delay_ms));
param_get(_parameter_handles.height_delay_ms, &(_parameters.height_delay_ms));
param_get(_parameter_handles.mag_delay_ms, &(_parameters.mag_delay_ms));
param_get(_parameter_handles.tas_delay_ms, &(_parameters.tas_delay_ms));
param_get(_parameter_handles.velne_noise, &(_parameters.velne_noise));
param_get(_parameter_handles.veld_noise, &(_parameters.veld_noise));
param_get(_parameter_handles.posne_noise, &(_parameters.posne_noise));
param_get(_parameter_handles.posd_noise, &(_parameters.posd_noise));
param_get(_parameter_handles.mag_noise, &(_parameters.mag_noise));
param_get(_parameter_handles.gyro_pnoise, &(_parameters.gyro_pnoise));
param_get(_parameter_handles.acc_pnoise, &(_parameters.acc_pnoise));
param_get(_parameter_handles.gbias_pnoise, &(_parameters.gbias_pnoise));
param_get(_parameter_handles.abias_pnoise, &(_parameters.abias_pnoise));
param_get(_parameter_handles.mage_pnoise, &(_parameters.mage_pnoise));
param_get(_parameter_handles.magb_pnoise, &(_parameters.magb_pnoise));
param_get(_parameter_handles.eas_noise, &(_parameters.eas_noise));
param_get(_parameter_handles.pos_stddev_threshold, &(_parameters.pos_stddev_threshold));
if (_ekf) {
// _ekf->yawVarScale = 1.0f;
// _ekf->windVelSigma = 0.1f;
_ekf->dAngBiasSigma = _parameters.gbias_pnoise;
_ekf->dVelBiasSigma = _parameters.abias_pnoise;
_ekf->magEarthSigma = _parameters.mage_pnoise;
_ekf->magBodySigma = _parameters.magb_pnoise;
// _ekf->gndHgtSigma = 0.02f;
_ekf->vneSigma = _parameters.velne_noise;
_ekf->vdSigma = _parameters.veld_noise;
_ekf->posNeSigma = _parameters.posne_noise;
_ekf->posDSigma = _parameters.posd_noise;
_ekf->magMeasurementSigma = _parameters.mag_noise;
_ekf->gyroProcessNoise = _parameters.gyro_pnoise;
_ekf->accelProcessNoise = _parameters.acc_pnoise;
_ekf->airspeedMeasurementSigma = _parameters.eas_noise;
_ekf->rngFinderPitch = 0.0f; // XXX base on SENS_BOARD_Y_OFF
}
return OK;
}
void AttitudePositionEstimatorEKF::vehicle_status_poll()
{
bool vstatus_updated;
/* Check HIL state if vehicle status has changed */
orb_check(_vstatus_sub, &vstatus_updated);
if (vstatus_updated) {
orb_copy(ORB_ID(vehicle_status), _vstatus_sub, &_vstatus);
//Tell EKF that the vehicle is a fixed wing or multi-rotor
_ekf->setIsFixedWing(!_vstatus.is_rotary_wing);
}
}
int AttitudePositionEstimatorEKF::check_filter_state()
{
/*
* CHECK IF THE INPUT DATA IS SANE
*/
struct ekf_status_report ekf_report;
int check = _ekf->CheckAndBound(&ekf_report);
const char *const feedback[] = { 0,
"NaN in states, resetting",
"stale sensor data, resetting",
"got initial position lock",
"excessive gyro offsets",
"velocity diverted, check accel config",
"excessive covariances",
"unknown condition, resetting"
};
// Print out error condition
if (check) {
unsigned warn_index = static_cast<unsigned>(check);
unsigned max_warn_index = (sizeof(feedback) / sizeof(feedback[0]));
if (max_warn_index < warn_index) {
warn_index = max_warn_index;
}
// Do not warn about accel offset if we have no position updates
if (!(warn_index == 5 && _ekf->staticMode)) {
warnx("reset: %s", feedback[warn_index]);
mavlink_log_critical(_mavlink_fd, "[ekf check] %s", feedback[warn_index]);
}
}
struct estimator_status_report rep;
memset(&rep, 0, sizeof(rep));
// If error flag is set, we got a filter reset
if (check && ekf_report.error) {
// Count the reset condition
perf_count(_perf_reset);
} else if (_ekf_logging) {
_ekf->GetFilterState(&ekf_report);
}
if (_ekf_logging || check) {
rep.timestamp = hrt_absolute_time();
rep.nan_flags |= (((uint8_t)ekf_report.angNaN) << 0);
rep.nan_flags |= (((uint8_t)ekf_report.summedDelVelNaN) << 1);
rep.nan_flags |= (((uint8_t)ekf_report.KHNaN) << 2);
rep.nan_flags |= (((uint8_t)ekf_report.KHPNaN) << 3);
rep.nan_flags |= (((uint8_t)ekf_report.PNaN) << 4);
rep.nan_flags |= (((uint8_t)ekf_report.covarianceNaN) << 5);
rep.nan_flags |= (((uint8_t)ekf_report.kalmanGainsNaN) << 6);
rep.nan_flags |= (((uint8_t)ekf_report.statesNaN) << 7);
rep.health_flags |= (((uint8_t)ekf_report.velHealth) << 0);
rep.health_flags |= (((uint8_t)ekf_report.posHealth) << 1);
rep.health_flags |= (((uint8_t)ekf_report.hgtHealth) << 2);
rep.health_flags |= (((uint8_t)!ekf_report.gyroOffsetsExcessive) << 3);
rep.health_flags |= (((uint8_t)ekf_report.onGround) << 4);
rep.health_flags |= (((uint8_t)ekf_report.staticMode) << 5);
rep.health_flags |= (((uint8_t)ekf_report.useCompass) << 6);
rep.health_flags |= (((uint8_t)ekf_report.useAirspeed) << 7);
rep.timeout_flags |= (((uint8_t)ekf_report.velTimeout) << 0);
rep.timeout_flags |= (((uint8_t)ekf_report.posTimeout) << 1);
rep.timeout_flags |= (((uint8_t)ekf_report.hgtTimeout) << 2);
rep.timeout_flags |= (((uint8_t)ekf_report.imuTimeout) << 3);
if (_debug > 10) {
if (rep.health_flags < ((1 << 0) | (1 << 1) | (1 << 2) | (1 << 3))) {
warnx("health: VEL:%s POS:%s HGT:%s OFFS:%s",
((rep.health_flags & (1 << 0)) ? "OK" : "ERR"),
((rep.health_flags & (1 << 1)) ? "OK" : "ERR"),
((rep.health_flags & (1 << 2)) ? "OK" : "ERR"),
((rep.health_flags & (1 << 3)) ? "OK" : "ERR"));
}
if (rep.timeout_flags) {
warnx("timeout: %s%s%s%s",
((rep.timeout_flags & (1 << 0)) ? "VEL " : ""),
((rep.timeout_flags & (1 << 1)) ? "POS " : ""),
((rep.timeout_flags & (1 << 2)) ? "HGT " : ""),
((rep.timeout_flags & (1 << 3)) ? "IMU " : ""));
}
}
// Copy all states or at least all that we can fit
size_t ekf_n_states = ekf_report.n_states;
size_t max_states = (sizeof(rep.states) / sizeof(rep.states[0]));
rep.n_states = (ekf_n_states < max_states) ? ekf_n_states : max_states;
for (size_t i = 0; i < rep.n_states; i++) {
rep.states[i] = ekf_report.states[i];
}
if (_estimator_status_pub > 0) {
orb_publish(ORB_ID(estimator_status), _estimator_status_pub, &rep);
} else {
_estimator_status_pub = orb_advertise(ORB_ID(estimator_status), &rep);
}
}
return check;
}
void AttitudePositionEstimatorEKF::task_main_trampoline(int argc, char *argv[])
{
estimator::g_estimator->task_main();
}
void AttitudePositionEstimatorEKF::task_main()
{
_mavlink_fd = open(MAVLINK_LOG_DEVICE, 0);
_ekf = new AttPosEKF();
_filter_start_time = hrt_absolute_time();
if (!_ekf) {
errx(1, "OUT OF MEM!");
}
/*
* do subscriptions
*/
_distance_sub = orb_subscribe(ORB_ID(sensor_range_finder));
_baro_sub = orb_subscribe_multi(ORB_ID(sensor_baro), 0);
_airspeed_sub = orb_subscribe(ORB_ID(airspeed));
_gps_sub = orb_subscribe(ORB_ID(vehicle_gps_position));
_vstatus_sub = orb_subscribe(ORB_ID(vehicle_status));
_params_sub = orb_subscribe(ORB_ID(parameter_update));
_home_sub = orb_subscribe(ORB_ID(home_position));
_landDetectorSub = orb_subscribe(ORB_ID(vehicle_land_detected));
_armedSub = orb_subscribe(ORB_ID(actuator_armed));
/* rate limit vehicle status updates to 5Hz */
orb_set_interval(_vstatus_sub, 200);
_sensor_combined_sub = orb_subscribe(ORB_ID(sensor_combined));
/* XXX remove this!, BUT increase the data buffer size! */
orb_set_interval(_sensor_combined_sub, 9);
/* sets also parameters in the EKF object */
parameters_update();
/* wakeup source(s) */
struct pollfd fds[2];
/* Setup of loop */
fds[0].fd = _params_sub;
fds[0].events = POLLIN;
fds[1].fd = _sensor_combined_sub;
fds[1].events = POLLIN;
_gps.vel_n_m_s = 0.0f;
_gps.vel_e_m_s = 0.0f;
_gps.vel_d_m_s = 0.0f;
_task_running = true;
while (!_task_should_exit) {
/* wait for up to 100ms for data */
int pret = poll(&fds[0], (sizeof(fds) / sizeof(fds[0])), 100);
/* timed out - periodic check for _task_should_exit, etc. */
if (pret == 0) {
continue;
}
/* this is undesirable but not much we can do - might want to flag unhappy status */
if (pret < 0) {
warn("POLL ERR %d, %d", pret, errno);
continue;
}
perf_begin(_loop_perf);
perf_count(_loop_intvl);
/* only update parameters if they changed */
if (fds[0].revents & POLLIN) {
/* read from param to clear updated flag */
struct parameter_update_s update;
orb_copy(ORB_ID(parameter_update), _params_sub, &update);
/* update parameters from storage */
parameters_update();
}
/* only run estimator if gyro updated */
if (fds[1].revents & POLLIN) {
/* check vehicle status for changes to publication state */
bool prev_hil = (_vstatus.hil_state == vehicle_status_s::HIL_STATE_ON);
vehicle_status_poll();
perf_count(_perf_gyro);
/* Reset baro reference if switching to HIL, reset sensor states */
if (!prev_hil && (_vstatus.hil_state == vehicle_status_s::HIL_STATE_ON)) {
/* system is in HIL now, wait for measurements to come in one last round */
usleep(60000);
/* now read all sensor publications to ensure all real sensor data is purged */
orb_copy(ORB_ID(sensor_combined), _sensor_combined_sub, &_sensor_combined);
/* set sensors to de-initialized state */
_gyro_valid = false;
_accel_valid = false;
_mag_valid = false;
_baro_init = false;
_gps_initialized = false;
_last_sensor_timestamp = hrt_absolute_time();
_last_run = _last_sensor_timestamp;
_ekf->ZeroVariables();
_ekf->dtIMU = 0.01f;
_filter_start_time = _last_sensor_timestamp;
/* now skip this loop and get data on the next one, which will also re-init the filter */
continue;
}
/**
* PART ONE: COLLECT ALL DATA
**/
pollData();
/*
* CHECK IF ITS THE RIGHT TIME TO RUN THINGS ALREADY
*/
if (hrt_elapsed_time(&_filter_start_time) < FILTER_INIT_DELAY) {
continue;
}
/**
* PART TWO: EXECUTE THE FILTER
*
* We run the filter only once all data has been fetched
**/
if (_baro_init && _gyro_valid && _accel_valid && _mag_valid) {
// maintain filtered baro and gps altitudes to calculate weather offset
// baro sample rate is ~70Hz and measurement bandwidth is high
// gps sample rate is 5Hz and altitude is assumed accurate when averaged over 30 seconds
// maintain heavily filtered values for both baro and gps altitude
// Assume the filtered output should be identical for both sensors
_baro_gps_offset = _baro_alt_filt - _gps_alt_filt;
// if (hrt_elapsed_time(&_last_debug_print) >= 5e6) {
// _last_debug_print = hrt_absolute_time();
// perf_print_counter(_perf_baro);
// perf_reset(_perf_baro);
// warnx("gpsoff: %5.1f, baro_alt_filt: %6.1f, gps_alt_filt: %6.1f, gpos.alt: %5.1f, lpos.z: %6.1f",
// (double)_baro_gps_offset,
// (double)_baro_alt_filt,
// (double)_gps_alt_filt,
// (double)_global_pos.alt,
// (double)_local_pos.z);
// }
/* Initialize the filter first */
if (!_ekf->statesInitialised) {
// North, East Down position (m)
float initVelNED[3] = {0.0f, 0.0f, 0.0f};
_ekf->posNE[0] = 0.0f;
_ekf->posNE[1] = 0.0f;
_local_pos.ref_alt = 0.0f;
_baro_ref_offset = 0.0f;
_baro_gps_offset = 0.0f;
_baro_alt_filt = _baro.altitude;
_ekf->InitialiseFilter(initVelNED, 0.0, 0.0, 0.0f, 0.0f);
} else {
if (!_gps_initialized && _gpsIsGood) {
initializeGPS();
continue;
}
// Check if on ground - status is used by covariance prediction
_ekf->setOnGround(_landDetector.landed);
// We're apparently initialized in this case now
// check (and reset the filter as needed)
int check = check_filter_state();
if (check) {
// Let the system re-initialize itself
continue;
}
//Run EKF data fusion steps
updateSensorFusion(_gpsIsGood, _newDataMag, _newRangeData, _newHgtData, _newAdsData);
//Publish attitude estimations
publishAttitude();
//Publish Local Position estimations
publishLocalPosition();
//Publish Global Position, but only if it's any good
if (_gps_initialized && (_gpsIsGood || _global_pos.dead_reckoning)) {
publishGlobalPosition();
}
//Publish wind estimates
if (hrt_elapsed_time(&_wind.timestamp) > 99000) {
publishWindEstimate();
}
}
}
}
perf_end(_loop_perf);
}
_task_running = false;
warnx("exiting.\n");
_estimator_task = -1;
_exit(0);
}
void AttitudePositionEstimatorEKF::initializeGPS()
{
// GPS is in scaled integers, convert
double lat = _gps.lat / 1.0e7;
double lon = _gps.lon / 1.0e7;
float gps_alt = _gps.alt / 1e3f;
// Set up height correctly
orb_copy(ORB_ID(sensor_baro), _baro_sub, &_baro);
_baro_ref_offset = _ekf->states[9]; // this should become zero in the local frame
// init filtered gps and baro altitudes
_gps_alt_filt = gps_alt;
_baro_alt_filt = _baro.altitude;
_ekf->baroHgt = _baro.altitude;
_ekf->hgtMea = _ekf->baroHgt;
// Set up position variables correctly
_ekf->GPSstatus = _gps.fix_type;
_ekf->gpsLat = math::radians(lat);
_ekf->gpsLon = math::radians(lon) - M_PI;
_ekf->gpsHgt = gps_alt;
// Look up mag declination based on current position
float declination = math::radians(get_mag_declination(lat, lon));
float initVelNED[3];
initVelNED[0] = _gps.vel_n_m_s;
initVelNED[1] = _gps.vel_e_m_s;
initVelNED[2] = _gps.vel_d_m_s;
_ekf->InitialiseFilter(initVelNED, math::radians(lat), math::radians(lon) - M_PI, gps_alt, declination);
// Initialize projection
_local_pos.ref_lat = lat;
_local_pos.ref_lon = lon;
_local_pos.ref_alt = gps_alt;
_local_pos.ref_timestamp = _gps.timestamp_position;
map_projection_init(&_pos_ref, lat, lon);
mavlink_log_info(_mavlink_fd, "[ekf] ref: LA %.4f,LO %.4f,ALT %.2f", lat, lon, (double)gps_alt);
#if 0
warnx("HOME/REF: LA %8.4f,LO %8.4f,ALT %8.2f V: %8.4f %8.4f %8.4f", lat, lon, (double)gps_alt,
(double)_ekf->velNED[0], (double)_ekf->velNED[1], (double)_ekf->velNED[2]);
warnx("BARO: %8.4f m / ref: %8.4f m / gps offs: %8.4f m", (double)_ekf->baroHgt, (double)_baro_ref,
(double)_baro_ref_offset);
warnx("GPS: eph: %8.4f, epv: %8.4f, declination: %8.4f", (double)_gps.eph, (double)_gps.epv,
(double)math::degrees(declination));
#endif
_gps_initialized = true;
}
void AttitudePositionEstimatorEKF::publishAttitude()
{
// Output results
math::Quaternion q(_ekf->states[0], _ekf->states[1], _ekf->states[2], _ekf->states[3]);
math::Matrix<3, 3> R = q.to_dcm();
math::Vector<3> euler = R.to_euler();
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
PX4_R(_att.R, i, j) = R(i, j);
}
}
_att.timestamp = _last_sensor_timestamp;
_att.q[0] = _ekf->states[0];
_att.q[1] = _ekf->states[1];
_att.q[2] = _ekf->states[2];
_att.q[3] = _ekf->states[3];
_att.q_valid = true;
_att.R_valid = true;
_att.timestamp = _last_sensor_timestamp;
_att.roll = euler(0);
_att.pitch = euler(1);
_att.yaw = euler(2);
_att.rollspeed = _ekf->angRate.x - _ekf->states[10] / _ekf->dtIMU;
_att.pitchspeed = _ekf->angRate.y - _ekf->states[11] / _ekf->dtIMU;
_att.yawspeed = _ekf->angRate.z - _ekf->states[12] / _ekf->dtIMU;
// gyro offsets
_att.rate_offsets[0] = _ekf->states[10] / _ekf->dtIMU;
_att.rate_offsets[1] = _ekf->states[11] / _ekf->dtIMU;
_att.rate_offsets[2] = _ekf->states[12] / _ekf->dtIMU;
/* lazily publish the attitude only once available */
if (_att_pub > 0) {
/* publish the attitude setpoint */
orb_publish(ORB_ID(vehicle_attitude), _att_pub, &_att);
} else {
/* advertise and publish */
_att_pub = orb_advertise(ORB_ID(vehicle_attitude), &_att);
}
}
void AttitudePositionEstimatorEKF::publishLocalPosition()
{
_local_pos.timestamp = _last_sensor_timestamp;
_local_pos.x = _ekf->states[7];
_local_pos.y = _ekf->states[8];
// XXX need to announce change of Z reference somehow elegantly
_local_pos.z = _ekf->states[9] - _baro_ref_offset - _baroAltRef;
_local_pos.vx = _ekf->states[4];
_local_pos.vy = _ekf->states[5];
_local_pos.vz = _ekf->states[6];
_local_pos.xy_valid = _gps_initialized && _gpsIsGood;
_local_pos.z_valid = true;
_local_pos.v_xy_valid = _gps_initialized && _gpsIsGood;
_local_pos.v_z_valid = true;
_local_pos.xy_global = _gps_initialized; //TODO: Handle optical flow mode here
_local_pos.z_global = false;
_local_pos.yaw = _att.yaw;
/* lazily publish the local position only once available */
if (_local_pos_pub > 0) {
/* publish the attitude setpoint */
orb_publish(ORB_ID(vehicle_local_position), _local_pos_pub, &_local_pos);
} else {
/* advertise and publish */
_local_pos_pub = orb_advertise(ORB_ID(vehicle_local_position), &_local_pos);
}
}
void AttitudePositionEstimatorEKF::publishGlobalPosition()
{
_global_pos.timestamp = _local_pos.timestamp;
if (_local_pos.xy_global) {
double est_lat, est_lon;
map_projection_reproject(&_pos_ref, _local_pos.x, _local_pos.y, &est_lat, &est_lon);
_global_pos.lat = est_lat;
_global_pos.lon = est_lon;
_global_pos.time_utc_usec = _gps.time_utc_usec;
}
if (_local_pos.v_xy_valid) {
_global_pos.vel_n = _local_pos.vx;
_global_pos.vel_e = _local_pos.vy;
} else {
_global_pos.vel_n = 0.0f;
_global_pos.vel_e = 0.0f;
}
/* local pos alt is negative, change sign and add alt offsets */
_global_pos.alt = (-_local_pos.z) - _baro_gps_offset;
if (_local_pos.v_z_valid) {
_global_pos.vel_d = _local_pos.vz;
}
/* terrain altitude */
_global_pos.terrain_alt = _ekf->hgtRef - _ekf->flowStates[1];
_global_pos.terrain_alt_valid = (_distance_last_valid > 0) &&
(hrt_elapsed_time(&_distance_last_valid) < 20 * 1000 * 1000);
_global_pos.yaw = _local_pos.yaw;
_global_pos.eph = _gps.eph;
_global_pos.epv = _gps.epv;
/* lazily publish the global position only once available */
if (_global_pos_pub > 0) {
/* publish the global position */
orb_publish(ORB_ID(vehicle_global_position), _global_pos_pub, &_global_pos);
} else {
/* advertise and publish */
_global_pos_pub = orb_advertise(ORB_ID(vehicle_global_position), &_global_pos);
}
}
void AttitudePositionEstimatorEKF::publishWindEstimate()
{
_wind.timestamp = _global_pos.timestamp;
_wind.windspeed_north = _ekf->states[14];
_wind.windspeed_east = _ekf->states[15];
// XXX we need to do something smart about the covariance here
// but we default to the estimate covariance for now
_wind.covariance_north = _ekf->P[14][14];
_wind.covariance_east = _ekf->P[15][15];
/* lazily publish the wind estimate only once available */
if (_wind_pub > 0) {
/* publish the wind estimate */
orb_publish(ORB_ID(wind_estimate), _wind_pub, &_wind);
} else {
/* advertise and publish */
_wind_pub = orb_advertise(ORB_ID(wind_estimate), &_wind);
}
}
void AttitudePositionEstimatorEKF::updateSensorFusion(const bool fuseGPS, const bool fuseMag,
const bool fuseRangeSensor, const bool fuseBaro, const bool fuseAirSpeed)
{
// Run the strapdown INS equations every IMU update
_ekf->UpdateStrapdownEquationsNED();
// store the predicted states for subsequent use by measurement fusion
_ekf->StoreStates(IMUmsec);
// sum delta angles and time used by covariance prediction
_ekf->summedDelAng = _ekf->summedDelAng + _ekf->correctedDelAng;
_ekf->summedDelVel = _ekf->summedDelVel + _ekf->dVelIMU;
_covariancePredictionDt += _ekf->dtIMU;
// perform a covariance prediction if the total delta angle has exceeded the limit
// or the time limit will be exceeded at the next IMU update
if ((_covariancePredictionDt >= (_ekf->covTimeStepMax - _ekf->dtIMU))
|| (_ekf->summedDelAng.length() > _ekf->covDelAngMax)) {
_ekf->CovariancePrediction(_covariancePredictionDt);
_ekf->summedDelAng.zero();
_ekf->summedDelVel.zero();
_covariancePredictionDt = 0.0f;
}
// Fuse GPS Measurements
if (fuseGPS && _gps_initialized) {
// Convert GPS measurements to Pos NE, hgt and Vel NED
// set fusion flags
_ekf->fuseVelData = true;
_ekf->fusePosData = true;
// recall states stored at time of measurement after adjusting for delays
_ekf->RecallStates(_ekf->statesAtVelTime, (IMUmsec - _parameters.vel_delay_ms));
_ekf->RecallStates(_ekf->statesAtPosTime, (IMUmsec - _parameters.pos_delay_ms));
// run the fusion step
_ekf->FuseVelposNED();
} else if (!_gps_initialized) {
// force static mode
_ekf->staticMode = true;
// Convert GPS measurements to Pos NE, hgt and Vel NED
_ekf->velNED[0] = 0.0f;
_ekf->velNED[1] = 0.0f;
_ekf->velNED[2] = 0.0f;
_ekf->posNE[0] = 0.0f;
_ekf->posNE[1] = 0.0f;
// set fusion flags
_ekf->fuseVelData = true;
_ekf->fusePosData = true;
// recall states stored at time of measurement after adjusting for delays
_ekf->RecallStates(_ekf->statesAtVelTime, (IMUmsec - _parameters.vel_delay_ms));
_ekf->RecallStates(_ekf->statesAtPosTime, (IMUmsec - _parameters.pos_delay_ms));
// run the fusion step
_ekf->FuseVelposNED();
} else {
_ekf->fuseVelData = false;
_ekf->fusePosData = false;
}
if (fuseBaro) {
// Could use a blend of GPS and baro alt data if desired
_ekf->hgtMea = _ekf->baroHgt;
_ekf->fuseHgtData = true;
// recall states stored at time of measurement after adjusting for delays
_ekf->RecallStates(_ekf->statesAtHgtTime, (IMUmsec - _parameters.height_delay_ms));
// run the fusion step
_ekf->FuseVelposNED();
} else {
_ekf->fuseHgtData = false;
}
// Fuse Magnetometer Measurements
if (fuseMag) {
_ekf->fuseMagData = true;
_ekf->RecallStates(_ekf->statesAtMagMeasTime,
(IMUmsec - _parameters.mag_delay_ms)); // Assume 50 msec avg delay for magnetometer data
_ekf->magstate.obsIndex = 0;
_ekf->FuseMagnetometer();
_ekf->FuseMagnetometer();
_ekf->FuseMagnetometer();
} else {
_ekf->fuseMagData = false;
}
// Fuse Airspeed Measurements
if (fuseAirSpeed && _ekf->VtasMeas > 7.0f) {
_ekf->fuseVtasData = true;
_ekf->RecallStates(_ekf->statesAtVtasMeasTime,
(IMUmsec - _parameters.tas_delay_ms)); // assume 100 msec avg delay for airspeed data
_ekf->FuseAirspeed();
} else {
_ekf->fuseVtasData = false;
}
// Fuse Rangefinder Measurements
if (fuseRangeSensor) {
if (_ekf->Tnb.z.z > 0.9f) {
// _ekf->rngMea is set in sensor readout already
_ekf->fuseRngData = true;
_ekf->fuseOptFlowData = false;
_ekf->RecallStates(_ekf->statesAtRngTime, (IMUmsec - 100.0f));
_ekf->OpticalFlowEKF();
_ekf->fuseRngData = false;
}
}
}
int AttitudePositionEstimatorEKF::start()
{
ASSERT(_estimator_task == -1);
/* start the task */
_estimator_task = task_spawn_cmd("ekf_att_pos_estimator",
SCHED_DEFAULT,
SCHED_PRIORITY_MAX - 40,
7500,
(main_t)&AttitudePositionEstimatorEKF::task_main_trampoline,
nullptr);
if (_estimator_task < 0) {
warn("task start failed");
return -errno;
}
return OK;
}
void AttitudePositionEstimatorEKF::print_status()
{
math::Quaternion q(_ekf->states[0], _ekf->states[1], _ekf->states[2], _ekf->states[3]);
math::Matrix<3, 3> R = q.to_dcm();
math::Vector<3> euler = R.to_euler();
printf("attitude: roll: %8.4f, pitch %8.4f, yaw: %8.4f degrees\n",
(double)math::degrees(euler(0)), (double)math::degrees(euler(1)), (double)math::degrees(euler(2)));
// State vector:
// 0-3: quaternions (q0, q1, q2, q3)
// 4-6: Velocity - m/sec (North, East, Down)
// 7-9: Position - m (North, East, Down)
// 10-12: Delta Angle bias - rad (X,Y,Z)
// 13: Delta Velocity Bias - m/s (Z)
// 14-15: Wind Vector - m/sec (North,East)
// 16-18: Earth Magnetic Field Vector - gauss (North, East, Down)
// 19-21: Body Magnetic Field Vector - gauss (X,Y,Z)
printf("dtIMU: %8.6f IMUmsec: %d\n", (double)_ekf->dtIMU, (int)IMUmsec);
printf("baro alt: %8.4f GPS alt: %8.4f\n", (double)_baro.altitude, (double)(_gps.alt / 1e3f));
printf("baro ref offset: %8.4f baro GPS offset: %8.4f\n", (double)_baro_ref_offset,
(double)_baro_gps_offset);
printf("dvel: %8.6f %8.6f %8.6f accel: %8.6f %8.6f %8.6f\n", (double)_ekf->dVelIMU.x, (double)_ekf->dVelIMU.y,
(double)_ekf->dVelIMU.z, (double)_ekf->accel.x, (double)_ekf->accel.y, (double)_ekf->accel.z);
printf("dang: %8.4f %8.4f %8.4f dang corr: %8.4f %8.4f %8.4f\n" , (double)_ekf->dAngIMU.x, (double)_ekf->dAngIMU.y,
(double)_ekf->dAngIMU.z, (double)_ekf->correctedDelAng.x, (double)_ekf->correctedDelAng.y,
(double)_ekf->correctedDelAng.z);
printf("states (quat) [0-3]: %8.4f, %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[0], (double)_ekf->states[1],
(double)_ekf->states[2], (double)_ekf->states[3]);
printf("states (vel m/s) [4-6]: %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[4], (double)_ekf->states[5],
(double)_ekf->states[6]);
printf("states (pos m) [7-9]: %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[7], (double)_ekf->states[8],
(double)_ekf->states[9]);
printf("states (delta ang) [10-12]: %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[10], (double)_ekf->states[11],
(double)_ekf->states[12]);
if (EKF_STATE_ESTIMATES == 23) {
printf("states (accel offs) [13]: %8.4f\n", (double)_ekf->states[13]);
printf("states (wind) [14-15]: %8.4f, %8.4f\n", (double)_ekf->states[14], (double)_ekf->states[15]);
printf("states (earth mag) [16-18]: %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[16], (double)_ekf->states[17],
(double)_ekf->states[18]);
printf("states (body mag) [19-21]: %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[19], (double)_ekf->states[20],
(double)_ekf->states[21]);
printf("states (terrain) [22]: %8.4f\n", (double)_ekf->states[22]);
} else {
printf("states (wind) [13-14]: %8.4f, %8.4f\n", (double)_ekf->states[13], (double)_ekf->states[14]);
printf("states (earth mag) [15-17]: %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[15], (double)_ekf->states[16],
(double)_ekf->states[17]);
printf("states (body mag) [18-20]: %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[18], (double)_ekf->states[19],
(double)_ekf->states[20]);
}
printf("states: %s %s %s %s %s %s %s %s %s %s\n",
(_ekf->statesInitialised) ? "INITIALIZED" : "NON_INIT",
(_landDetector.landed) ? "ON_GROUND" : "AIRBORNE",
(_ekf->fuseVelData) ? "FUSE_VEL" : "INH_VEL",
(_ekf->fusePosData) ? "FUSE_POS" : "INH_POS",
(_ekf->fuseHgtData) ? "FUSE_HGT" : "INH_HGT",
(_ekf->fuseMagData) ? "FUSE_MAG" : "INH_MAG",
(_ekf->fuseVtasData) ? "FUSE_VTAS" : "INH_VTAS",
(_ekf->useAirspeed) ? "USE_AIRSPD" : "IGN_AIRSPD",
(_ekf->useCompass) ? "USE_COMPASS" : "IGN_COMPASS",
(_ekf->staticMode) ? "STATIC_MODE" : "DYNAMIC_MODE");
}
void AttitudePositionEstimatorEKF::pollData()
{
//Update arming status
bool armedUpdate;
orb_check(_armedSub, &armedUpdate);
if (armedUpdate) {
orb_copy(ORB_ID(actuator_armed), _armedSub, &_armed);
}
//Update Gyro and Accelerometer
static Vector3f lastAngRate;
static Vector3f lastAccel;
bool accel_updated = false;
orb_copy(ORB_ID(sensor_combined), _sensor_combined_sub, &_sensor_combined);
static hrt_abstime last_accel = 0;
static hrt_abstime last_mag = 0;
if (last_accel != _sensor_combined.accelerometer_timestamp) {
accel_updated = true;
} else {
accel_updated = false;
}
last_accel = _sensor_combined.accelerometer_timestamp;
// Copy gyro and accel
_last_sensor_timestamp = _sensor_combined.timestamp;
IMUmsec = _sensor_combined.timestamp / 1e3;
IMUusec = _sensor_combined.timestamp;
float deltaT = (_sensor_combined.timestamp - _last_run) / 1e6f;
/* guard against too large deltaT's */
if (!isfinite(deltaT) || deltaT > 1.0f || deltaT < 0.000001f) {
deltaT = 0.01f;
}
_last_run = _sensor_combined.timestamp;
// Always store data, independent of init status
/* fill in last data set */
_ekf->dtIMU = deltaT;
int last_gyro_main = _gyro_main;
if (isfinite(_sensor_combined.gyro_rad_s[0]) &&
isfinite(_sensor_combined.gyro_rad_s[1]) &&
isfinite(_sensor_combined.gyro_rad_s[2]) &&
(_sensor_combined.gyro_errcount <= _sensor_combined.gyro1_errcount)) {
_ekf->angRate.x = _sensor_combined.gyro_rad_s[0];
_ekf->angRate.y = _sensor_combined.gyro_rad_s[1];
_ekf->angRate.z = _sensor_combined.gyro_rad_s[2];
_gyro_main = 0;
_gyro_valid = true;
} else if (isfinite(_sensor_combined.gyro1_rad_s[0]) &&
isfinite(_sensor_combined.gyro1_rad_s[1]) &&
isfinite(_sensor_combined.gyro1_rad_s[2])) {
_ekf->angRate.x = _sensor_combined.gyro1_rad_s[0];
_ekf->angRate.y = _sensor_combined.gyro1_rad_s[1];
_ekf->angRate.z = _sensor_combined.gyro1_rad_s[2];
_gyro_main = 1;
_gyro_valid = true;
} else {
_gyro_valid = false;
}
if (last_gyro_main != _gyro_main) {
mavlink_and_console_log_emergency(_mavlink_fd, "GYRO FAILED! Switched from #%d to %d", last_gyro_main, _gyro_main);
}
if (!_gyro_valid) {
/* keep last value if he hit an out of band value */
lastAngRate = _ekf->angRate;
} else {
perf_count(_perf_gyro);
}
if (accel_updated) {
int last_accel_main = _accel_main;
/* fail over to the 2nd accel if we know the first is down */
if (_sensor_combined.accelerometer_errcount <= _sensor_combined.accelerometer1_errcount) {
_ekf->accel.x = _sensor_combined.accelerometer_m_s2[0];
_ekf->accel.y = _sensor_combined.accelerometer_m_s2[1];
_ekf->accel.z = _sensor_combined.accelerometer_m_s2[2];
_accel_main = 0;
} else {
_ekf->accel.x = _sensor_combined.accelerometer1_m_s2[0];
_ekf->accel.y = _sensor_combined.accelerometer1_m_s2[1];
_ekf->accel.z = _sensor_combined.accelerometer1_m_s2[2];
_accel_main = 1;
}
if (!_accel_valid) {
lastAccel = _ekf->accel;
}
if (last_accel_main != _accel_main) {
mavlink_and_console_log_emergency(_mavlink_fd, "ACCEL FAILED! Switched from #%d to %d", last_accel_main, _accel_main);
}
_accel_valid = true;
}
_ekf->dAngIMU = 0.5f * (_ekf->angRate + lastAngRate) * _ekf->dtIMU;
lastAngRate = _ekf->angRate;
_ekf->dVelIMU = 0.5f * (_ekf->accel + lastAccel) * _ekf->dtIMU;
lastAccel = _ekf->accel;
if (last_mag != _sensor_combined.magnetometer_timestamp) {
_newDataMag = true;
} else {
_newDataMag = false;
}
last_mag = _sensor_combined.magnetometer_timestamp;
//warnx("dang: %8.4f %8.4f dvel: %8.4f %8.4f", _ekf->dAngIMU.x, _ekf->dAngIMU.z, _ekf->dVelIMU.x, _ekf->dVelIMU.z);
//Update Land Detector
bool newLandData;
orb_check(_landDetectorSub, &newLandData);
if (newLandData) {
orb_copy(ORB_ID(vehicle_land_detected), _landDetectorSub, &_landDetector);
}
//Update AirSpeed
orb_check(_airspeed_sub, &_newAdsData);
if (_newAdsData) {
orb_copy(ORB_ID(airspeed), _airspeed_sub, &_airspeed);
perf_count(_perf_airspeed);
_ekf->VtasMeas = _airspeed.true_airspeed_m_s;
}
bool gps_update;
orb_check(_gps_sub, &gps_update);
if (gps_update) {
orb_copy(ORB_ID(vehicle_gps_position), _gps_sub, &_gps);
perf_count(_perf_gps);
//We are more strict for our first fix
float requiredAccuracy = _parameters.pos_stddev_threshold;
if (_gpsIsGood) {
requiredAccuracy = _parameters.pos_stddev_threshold * 2.0f;
}
//Check if the GPS fix is good enough for us to use
if (_gps.fix_type >= 3 && _gps.eph < requiredAccuracy && _gps.epv < requiredAccuracy) {
_gpsIsGood = true;
} else {
_gpsIsGood = false;
}
if (_gpsIsGood) {
//Calculate time since last good GPS fix
const float dtLastGoodGPS = static_cast<float>(_gps.timestamp_position - _previousGPSTimestamp) / 1e6f;
//Stop dead-reckoning mode
if (_global_pos.dead_reckoning) {
mavlink_log_info(_mavlink_fd, "[ekf] stop dead-reckoning");
}
_global_pos.dead_reckoning = false;
//Fetch new GPS data
_ekf->GPSstatus = _gps.fix_type;
_ekf->velNED[0] = _gps.vel_n_m_s;
_ekf->velNED[1] = _gps.vel_e_m_s;
_ekf->velNED[2] = _gps.vel_d_m_s;
_ekf->gpsLat = math::radians(_gps.lat / (double)1e7);
_ekf->gpsLon = math::radians(_gps.lon / (double)1e7) - M_PI;
_ekf->gpsHgt = _gps.alt / 1e3f;
if (_previousGPSTimestamp != 0) {
//Calculate average time between GPS updates
_ekf->updateDtGpsFilt(math::constrain(dtLastGoodGPS, 0.01f, POS_RESET_THRESHOLD));
// update LPF
_gps_alt_filt += (dtLastGoodGPS / (rc + dtLastGoodGPS)) * (_ekf->gpsHgt - _gps_alt_filt);
}
//check if we had a GPS outage for a long time
if (_gps_initialized) {
//Convert from global frame to local frame
map_projection_project(&_pos_ref, (_gps.lat / 1.0e7), (_gps.lon / 1.0e7), &_ekf->posNE[0], &_ekf->posNE[1]);
if (dtLastGoodGPS > POS_RESET_THRESHOLD) {
_ekf->ResetPosition();
_ekf->ResetVelocity();
}
}
//warnx("gps alt: %6.1f, interval: %6.3f", (double)_ekf->gpsHgt, (double)dtGoodGPS);
// if (_gps.s_variance_m_s > 0.25f && _gps.s_variance_m_s < 100.0f * 100.0f) {
// _ekf->vneSigma = sqrtf(_gps.s_variance_m_s);
// } else {
// _ekf->vneSigma = _parameters.velne_noise;
// }
// if (_gps.p_variance_m > 0.25f && _gps.p_variance_m < 100.0f * 100.0f) {
// _ekf->posNeSigma = sqrtf(_gps.p_variance_m);
// } else {
// _ekf->posNeSigma = _parameters.posne_noise;
// }
// warnx("vel: %8.4f pos: %8.4f", _gps.s_variance_m_s, _gps.p_variance_m);
_previousGPSTimestamp = _gps.timestamp_position;
}
}
// If it has gone more than POS_RESET_THRESHOLD amount of seconds since we received a GPS update,
// then something is very wrong with the GPS (possibly a hardware failure or comlink error)
const float dtLastGoodGPS = static_cast<float>(_gps.timestamp_position - _previousGPSTimestamp) / 1e6f;
if (dtLastGoodGPS >= POS_RESET_THRESHOLD) {
if (_global_pos.dead_reckoning) {
mavlink_log_info(_mavlink_fd, "[ekf] gave up dead-reckoning after long timeout");
}
_gpsIsGood = false;
_global_pos.dead_reckoning = false;
}
//If we have no good GPS fix for half a second, then enable dead-reckoning mode while armed (for up to POS_RESET_THRESHOLD seconds)
else if (dtLastGoodGPS >= 0.5f) {
if (_armed.armed) {
if (!_global_pos.dead_reckoning) {
mavlink_log_info(_mavlink_fd, "[ekf] dead-reckoning enabled");
}
_global_pos.dead_reckoning = true;
} else {
_global_pos.dead_reckoning = false;
}
}
//Update barometer
orb_check(_baro_sub, &_newHgtData);
if (_newHgtData) {
static hrt_abstime baro_last = 0;
orb_copy(ORB_ID(sensor_baro), _baro_sub, &_baro);
// init lowpass filters for baro and gps altitude
float baro_elapsed;
if (baro_last == 0) {
baro_elapsed = 0.0f;
} else {
baro_elapsed = (_baro.timestamp - baro_last) / 1e6f;
}
baro_last = _baro.timestamp;
if(!_baro_init) {
_baro_init = true;
_baroAltRef = _baro.altitude;
}
_ekf->updateDtHgtFilt(math::constrain(baro_elapsed, 0.001f, 0.1f));
_ekf->baroHgt = _baro.altitude;
_baro_alt_filt += (baro_elapsed / (rc + baro_elapsed)) * (_baro.altitude - _baro_alt_filt);
perf_count(_perf_baro);
}
//Update Magnetometer
if (_newDataMag) {
_mag_valid = true;
perf_count(_perf_mag);
int last_mag_main = _mag_main;
// XXX we compensate the offsets upfront - should be close to zero.
/* fail over to the 2nd mag if we know the first is down */
if (_sensor_combined.magnetometer_errcount <= _sensor_combined.magnetometer1_errcount) {
_ekf->magData.x = _sensor_combined.magnetometer_ga[0];
_ekf->magBias.x = 0.000001f; // _mag_offsets.x_offset
_ekf->magData.y = _sensor_combined.magnetometer_ga[1];
_ekf->magBias.y = 0.000001f; // _mag_offsets.y_offset
_ekf->magData.z = _sensor_combined.magnetometer_ga[2];
_ekf->magBias.z = 0.000001f; // _mag_offsets.y_offset
_mag_main = 0;
} else {
_ekf->magData.x = _sensor_combined.magnetometer1_ga[0];
_ekf->magBias.x = 0.000001f; // _mag_offsets.x_offset
_ekf->magData.y = _sensor_combined.magnetometer1_ga[1];
_ekf->magBias.y = 0.000001f; // _mag_offsets.y_offset
_ekf->magData.z = _sensor_combined.magnetometer1_ga[2];
_ekf->magBias.z = 0.000001f; // _mag_offsets.y_offset
_mag_main = 1;
}
if (last_mag_main != _mag_main) {
mavlink_and_console_log_emergency(_mavlink_fd, "MAG FAILED! Switched from #%d to %d", last_mag_main, _mag_main);
}
}
//Update range data
orb_check(_distance_sub, &_newRangeData);
if (_newRangeData) {
orb_copy(ORB_ID(sensor_range_finder), _distance_sub, &_distance);
if (_distance.valid) {
_ekf->rngMea = _distance.distance;
_distance_last_valid = _distance.timestamp;
} else {
_newRangeData = false;
}
}
}
int AttitudePositionEstimatorEKF::trip_nan()
{
int ret = 0;
// If system is not armed, inject a NaN value into the filter
if (_armed.armed) {
warnx("ACTUATORS ARMED! NOT TRIPPING SYSTEM");
ret = 1;
} else {
float nan_val = 0.0f / 0.0f;
warnx("system not armed, tripping state vector with NaN values");
_ekf->states[5] = nan_val;
usleep(100000);
warnx("tripping covariance #1 with NaN values");
_ekf->KH[2][2] = nan_val; // intermediate result used for covariance updates
usleep(100000);
warnx("tripping covariance #2 with NaN values");
_ekf->KHP[5][5] = nan_val; // intermediate result used for covariance updates
usleep(100000);
warnx("tripping covariance #3 with NaN values");
_ekf->P[3][3] = nan_val; // covariance matrix
usleep(100000);
warnx("tripping Kalman gains with NaN values");
_ekf->Kfusion[0] = nan_val; // Kalman gains
usleep(100000);
warnx("tripping stored states[0] with NaN values");
_ekf->storedStates[0][0] = nan_val;
usleep(100000);
warnx("\nDONE - FILTER STATE:");
print_status();
}
return ret;
}
int ekf_att_pos_estimator_main(int argc, char *argv[])
{
if (argc < 1) {
errx(1, "usage: ekf_att_pos_estimator {start|stop|status|logging}");
}
if (!strcmp(argv[1], "start")) {
if (estimator::g_estimator != nullptr) {
errx(1, "already running");
}
estimator::g_estimator = new AttitudePositionEstimatorEKF();
if (estimator::g_estimator == nullptr) {
errx(1, "alloc failed");
}
if (OK != estimator::g_estimator->start()) {
delete estimator::g_estimator;
estimator::g_estimator = nullptr;
err(1, "start failed");
}
/* avoid memory fragmentation by not exiting start handler until the task has fully started */
while (estimator::g_estimator == nullptr || !estimator::g_estimator->task_running()) {
usleep(50000);
printf(".");
fflush(stdout);
}
printf("\n");
exit(0);
}
if (!strcmp(argv[1], "stop")) {
if (estimator::g_estimator == nullptr) {
errx(1, "not running");
}
delete estimator::g_estimator;
estimator::g_estimator = nullptr;
exit(0);
}
if (!strcmp(argv[1], "status")) {
if (estimator::g_estimator) {
warnx("running");
estimator::g_estimator->print_status();
exit(0);
} else {
errx(1, "not running");
}
}
if (!strcmp(argv[1], "trip")) {
if (estimator::g_estimator) {
int ret = estimator::g_estimator->trip_nan();
exit(ret);
} else {
errx(1, "not running");
}
}
if (!strcmp(argv[1], "logging")) {
if (estimator::g_estimator) {
int ret = estimator::g_estimator->enable_logging(true);
exit(ret);
} else {
errx(1, "not running");
}
}
if (!strcmp(argv[1], "debug")) {
if (estimator::g_estimator) {
int debug = strtoul(argv[2], NULL, 10);
int ret = estimator::g_estimator->set_debuglevel(debug);
exit(ret);
} else {
errx(1, "not running");
}
}
warnx("unrecognized command");
return 1;
}