예제 #1
0
void Ekf2::task_main()
{
	// subscribe to relevant topics
	int sensors_sub = orb_subscribe(ORB_ID(sensor_combined));
	int gps_sub = orb_subscribe(ORB_ID(vehicle_gps_position));
	int airspeed_sub = orb_subscribe(ORB_ID(airspeed));
	int params_sub = orb_subscribe(ORB_ID(parameter_update));
	int optical_flow_sub = orb_subscribe(ORB_ID(optical_flow));
	int range_finder_sub = orb_subscribe(ORB_ID(distance_sensor));
	int ev_pos_sub = orb_subscribe(ORB_ID(vehicle_vision_position));
	int ev_att_sub = orb_subscribe(ORB_ID(vehicle_vision_attitude));
	int vehicle_land_detected_sub = orb_subscribe(ORB_ID(vehicle_land_detected));
	int status_sub = orb_subscribe(ORB_ID(vehicle_status));

	px4_pollfd_struct_t fds[2] = {};
	fds[0].fd = sensors_sub;
	fds[0].events = POLLIN;
	fds[1].fd = params_sub;
	fds[1].events = POLLIN;

	// initialise parameter cache
	updateParams();

	// initialize data structures outside of loop
	// because they will else not always be
	// properly populated
	sensor_combined_s sensors = {};
	vehicle_gps_position_s gps = {};
	airspeed_s airspeed = {};
	optical_flow_s optical_flow = {};
	distance_sensor_s range_finder = {};
	vehicle_land_detected_s vehicle_land_detected = {};
	vehicle_local_position_s ev_pos = {};
	vehicle_attitude_s ev_att = {};
	vehicle_status_s vehicle_status = {};

	while (!_task_should_exit) {
		int ret = px4_poll(fds, sizeof(fds) / sizeof(fds[0]), 1000);

		if (ret < 0) {
			// Poll error, sleep and try again
			usleep(10000);
			continue;

		} else if (ret == 0) {
			// Poll timeout or no new data, do nothing
			continue;
		}

		if (fds[1].revents & POLLIN) {
			// read from param to clear updated flag
			struct parameter_update_s update;
			orb_copy(ORB_ID(parameter_update), params_sub, &update);
			updateParams();

			// fetch sensor data in next loop
			continue;

		} else if (!(fds[0].revents & POLLIN)) {
			// no new data
			continue;
		}

		bool gps_updated = false;
		bool airspeed_updated = false;
		bool optical_flow_updated = false;
		bool range_finder_updated = false;
		bool vehicle_land_detected_updated = false;
		bool vision_position_updated = false;
		bool vision_attitude_updated = false;
		bool vehicle_status_updated = false;

		orb_copy(ORB_ID(sensor_combined), sensors_sub, &sensors);
		// update all other topics if they have new data

		orb_check(status_sub, &vehicle_status_updated);

		if (vehicle_status_updated) {
			orb_copy(ORB_ID(vehicle_status), status_sub, &vehicle_status);
		}

		orb_check(gps_sub, &gps_updated);

		if (gps_updated) {
			orb_copy(ORB_ID(vehicle_gps_position), gps_sub, &gps);
		}

		orb_check(airspeed_sub, &airspeed_updated);

		if (airspeed_updated) {
			orb_copy(ORB_ID(airspeed), airspeed_sub, &airspeed);
		}

		orb_check(optical_flow_sub, &optical_flow_updated);

		if (optical_flow_updated) {
			orb_copy(ORB_ID(optical_flow), optical_flow_sub, &optical_flow);
		}

		orb_check(range_finder_sub, &range_finder_updated);

		if (range_finder_updated) {
			orb_copy(ORB_ID(distance_sensor), range_finder_sub, &range_finder);

			if (range_finder.min_distance > range_finder.current_distance
			    || range_finder.max_distance < range_finder.current_distance) {
				range_finder_updated = false;
			}
		}

		orb_check(ev_pos_sub, &vision_position_updated);

		if (vision_position_updated) {
			orb_copy(ORB_ID(vehicle_vision_position), ev_pos_sub, &ev_pos);
		}

		orb_check(ev_att_sub, &vision_attitude_updated);

		if (vision_attitude_updated) {
			orb_copy(ORB_ID(vehicle_vision_attitude), ev_att_sub, &ev_att);
		}

		// in replay mode we are getting the actual timestamp from the sensor topic
		hrt_abstime now = 0;

		if (_replay_mode) {
			now = sensors.timestamp;

		} else {
			now = hrt_absolute_time();
		}

		// push imu data into estimator
		float gyro_integral[3];
		gyro_integral[0] = sensors.gyro_rad[0] * sensors.gyro_integral_dt;
		gyro_integral[1] = sensors.gyro_rad[1] * sensors.gyro_integral_dt;
		gyro_integral[2] = sensors.gyro_rad[2] * sensors.gyro_integral_dt;
		float accel_integral[3];
		accel_integral[0] = sensors.accelerometer_m_s2[0] * sensors.accelerometer_integral_dt;
		accel_integral[1] = sensors.accelerometer_m_s2[1] * sensors.accelerometer_integral_dt;
		accel_integral[2] = sensors.accelerometer_m_s2[2] * sensors.accelerometer_integral_dt;
		_ekf.setIMUData(now, sensors.gyro_integral_dt * 1.e6f, sensors.accelerometer_integral_dt * 1.e6f,
				gyro_integral, accel_integral);

		// read mag data
		if (sensors.magnetometer_timestamp_relative == sensor_combined_s::RELATIVE_TIMESTAMP_INVALID) {
			// set a zero timestamp to let the ekf replay program know that this data is not valid
			_timestamp_mag_us = 0;

		} else {
			if ((sensors.timestamp + sensors.magnetometer_timestamp_relative) != _timestamp_mag_us) {
				_timestamp_mag_us = sensors.timestamp + sensors.magnetometer_timestamp_relative;

				// If the time last used by the EKF is less than specified, then accumulate the
				// data and push the average when the 50msec is reached.
				_mag_time_sum_ms += _timestamp_mag_us / 1000;
				_mag_sample_count++;
				_mag_data_sum[0] += sensors.magnetometer_ga[0];
				_mag_data_sum[1] += sensors.magnetometer_ga[1];
				_mag_data_sum[2] += sensors.magnetometer_ga[2];
				uint32_t mag_time_ms = _mag_time_sum_ms / _mag_sample_count;

				if (mag_time_ms - _mag_time_ms_last_used > _params->sensor_interval_min_ms) {
					float mag_sample_count_inv = 1.0f / (float)_mag_sample_count;
					float mag_data_avg_ga[3] = {_mag_data_sum[0] *mag_sample_count_inv, _mag_data_sum[1] *mag_sample_count_inv, _mag_data_sum[2] *mag_sample_count_inv};
					_ekf.setMagData(1000 * (uint64_t)mag_time_ms, mag_data_avg_ga);
					_mag_time_ms_last_used = mag_time_ms;
					_mag_time_sum_ms = 0;
					_mag_sample_count = 0;
					_mag_data_sum[0] = 0.0f;
					_mag_data_sum[1] = 0.0f;
					_mag_data_sum[2] = 0.0f;

				}
			}
		}

		// read baro data
		if (sensors.baro_timestamp_relative == sensor_combined_s::RELATIVE_TIMESTAMP_INVALID) {
			// set a zero timestamp to let the ekf replay program know that this data is not valid
			_timestamp_balt_us = 0;

		} else {
			if ((sensors.timestamp + sensors.baro_timestamp_relative) != _timestamp_balt_us) {
				_timestamp_balt_us = sensors.timestamp + sensors.baro_timestamp_relative;

				// If the time last used by the EKF is less than specified, then accumulate the
				// data and push the average when the 50msec is reached.
				_balt_time_sum_ms += _timestamp_balt_us / 1000;
				_balt_sample_count++;
				_balt_data_sum += sensors.baro_alt_meter;
				uint32_t balt_time_ms = _balt_time_sum_ms / _balt_sample_count;

				if (balt_time_ms - _balt_time_ms_last_used > (uint32_t)_params->sensor_interval_min_ms) {
					float balt_data_avg = _balt_data_sum / (float)_balt_sample_count;
					_ekf.setBaroData(1000 * (uint64_t)balt_time_ms, balt_data_avg);
					_balt_time_ms_last_used = balt_time_ms;
					_balt_time_sum_ms = 0;
					_balt_sample_count = 0;
					_balt_data_sum = 0.0f;

				}
			}
		}

		// read gps data if available
		if (gps_updated) {
			struct gps_message gps_msg = {};
			gps_msg.time_usec = gps.timestamp;
			gps_msg.lat = gps.lat;
			gps_msg.lon = gps.lon;
			gps_msg.alt = gps.alt;
			gps_msg.fix_type = gps.fix_type;
			gps_msg.eph = gps.eph;
			gps_msg.epv = gps.epv;
			gps_msg.sacc = gps.s_variance_m_s;
			gps_msg.vel_m_s = gps.vel_m_s;
			gps_msg.vel_ned[0] = gps.vel_n_m_s;
			gps_msg.vel_ned[1] = gps.vel_e_m_s;
			gps_msg.vel_ned[2] = gps.vel_d_m_s;
			gps_msg.vel_ned_valid = gps.vel_ned_valid;
			gps_msg.nsats = gps.satellites_used;
			//TODO add gdop to gps topic
			gps_msg.gdop = 0.0f;

			_ekf.setGpsData(gps.timestamp, &gps_msg);

		}

		// only set airspeed data if condition for airspeed fusion are met
		bool fuse_airspeed = airspeed_updated && !vehicle_status.is_rotary_wing
				     && _arspFusionThreshold.get() <= airspeed.true_airspeed_m_s && _arspFusionThreshold.get() >= 0.1f;

		if (fuse_airspeed) {
			float eas2tas = airspeed.true_airspeed_m_s / airspeed.indicated_airspeed_m_s;
			_ekf.setAirspeedData(airspeed.timestamp, airspeed.true_airspeed_m_s, eas2tas);
		}

		// only fuse synthetic sideslip measurements if conditions are met
		bool fuse_beta = !vehicle_status.is_rotary_wing && _fuseBeta.get();
		_ekf.set_fuse_beta_flag(fuse_beta);

		if (optical_flow_updated) {
			flow_message flow;
			flow.flowdata(0) = optical_flow.pixel_flow_x_integral;
			flow.flowdata(1) = optical_flow.pixel_flow_y_integral;
			flow.quality = optical_flow.quality;
			flow.gyrodata(0) = optical_flow.gyro_x_rate_integral;
			flow.gyrodata(1) = optical_flow.gyro_y_rate_integral;
			flow.gyrodata(2) = optical_flow.gyro_z_rate_integral;
			flow.dt = optical_flow.integration_timespan;

			if (PX4_ISFINITE(optical_flow.pixel_flow_y_integral) &&
			    PX4_ISFINITE(optical_flow.pixel_flow_x_integral)) {
				_ekf.setOpticalFlowData(optical_flow.timestamp, &flow);
			}
		}

		if (range_finder_updated) {
			_ekf.setRangeData(range_finder.timestamp, range_finder.current_distance);
		}

		// get external vision data
		// if error estimates are unavailable, use parameter defined defaults
		if (vision_position_updated || vision_attitude_updated) {
			ext_vision_message ev_data;
			ev_data.posNED(0) = ev_pos.x;
			ev_data.posNED(1) = ev_pos.y;
			ev_data.posNED(2) = ev_pos.z;
			Quaternion q(ev_att.q);
			ev_data.quat = q;

			// position measurement error from parameters. TODO : use covariances from topic
			ev_data.posErr = _default_ev_pos_noise;
			ev_data.angErr = _default_ev_ang_noise;

			// use timestamp from external computer, clocks are synchronized when using MAVROS
			_ekf.setExtVisionData(vision_position_updated ? ev_pos.timestamp : ev_att.timestamp, &ev_data);
		}

		orb_check(vehicle_land_detected_sub, &vehicle_land_detected_updated);

		if (vehicle_land_detected_updated) {
			orb_copy(ORB_ID(vehicle_land_detected), vehicle_land_detected_sub, &vehicle_land_detected);
			_ekf.set_in_air_status(!vehicle_land_detected.landed);
		}

		// run the EKF update and output
		if (_ekf.update()) {

			matrix::Quaternion<float> q;
			_ekf.copy_quaternion(q.data());

			float velocity[3];
			_ekf.get_velocity(velocity);

			float gyro_rad[3];

			{
				// generate control state data
				control_state_s ctrl_state = {};
				float gyro_bias[3] = {};
				_ekf.get_gyro_bias(gyro_bias);
				ctrl_state.timestamp = _replay_mode ? now : hrt_absolute_time();
				gyro_rad[0] = sensors.gyro_rad[0] - gyro_bias[0];
				gyro_rad[1] = sensors.gyro_rad[1] - gyro_bias[1];
				gyro_rad[2] = sensors.gyro_rad[2] - gyro_bias[2];
				ctrl_state.roll_rate = _lp_roll_rate.apply(gyro_rad[0]);
				ctrl_state.pitch_rate = _lp_pitch_rate.apply(gyro_rad[1]);
				ctrl_state.yaw_rate = _lp_yaw_rate.apply(gyro_rad[2]);
				ctrl_state.roll_rate_bias = gyro_bias[0];
				ctrl_state.pitch_rate_bias = gyro_bias[1];
				ctrl_state.yaw_rate_bias = gyro_bias[2];

				// Velocity in body frame
				Vector3f v_n(velocity);
				matrix::Dcm<float> R_to_body(q.inversed());
				Vector3f v_b = R_to_body * v_n;
				ctrl_state.x_vel = v_b(0);
				ctrl_state.y_vel = v_b(1);
				ctrl_state.z_vel = v_b(2);


				// Local Position NED
				float position[3];
				_ekf.get_position(position);
				ctrl_state.x_pos = position[0];
				ctrl_state.y_pos = position[1];
				ctrl_state.z_pos = position[2];

				// Attitude quaternion
				q.copyTo(ctrl_state.q);

				_ekf.get_quat_reset(&ctrl_state.delta_q_reset[0], &ctrl_state.quat_reset_counter);

				// Acceleration data
				matrix::Vector<float, 3> acceleration(sensors.accelerometer_m_s2);

				float accel_bias[3];
				_ekf.get_accel_bias(accel_bias);
				ctrl_state.x_acc = acceleration(0) - accel_bias[0];
				ctrl_state.y_acc = acceleration(1) - accel_bias[1];
				ctrl_state.z_acc = acceleration(2) - accel_bias[2];

				// compute lowpass filtered horizontal acceleration
				acceleration = R_to_body.transpose() * acceleration;
				_acc_hor_filt = 0.95f * _acc_hor_filt + 0.05f * sqrtf(acceleration(0) * acceleration(0) +
						acceleration(1) * acceleration(1));
				ctrl_state.horz_acc_mag = _acc_hor_filt;

				ctrl_state.airspeed_valid = false;

				// use estimated velocity for airspeed estimate
				if (_airspeed_mode.get() == control_state_s::AIRSPD_MODE_MEAS) {
					// use measured airspeed
					if (PX4_ISFINITE(airspeed.indicated_airspeed_m_s) && hrt_absolute_time() - airspeed.timestamp < 1e6
					    && airspeed.timestamp > 0) {
						ctrl_state.airspeed = airspeed.indicated_airspeed_m_s;
						ctrl_state.airspeed_valid = true;
					}

				} else if (_airspeed_mode.get() == control_state_s::AIRSPD_MODE_EST) {
					if (_ekf.local_position_is_valid()) {
						ctrl_state.airspeed = sqrtf(velocity[0] * velocity[0] + velocity[1] * velocity[1] + velocity[2] * velocity[2]);
						ctrl_state.airspeed_valid = true;
					}

				} else if (_airspeed_mode.get() == control_state_s::AIRSPD_MODE_DISABLED) {
					// do nothing, airspeed has been declared as non-valid above, controllers
					// will handle this assuming always trim airspeed
				}

				// publish control state data
				if (_control_state_pub == nullptr) {
					_control_state_pub = orb_advertise(ORB_ID(control_state), &ctrl_state);

				} else {
					orb_publish(ORB_ID(control_state), _control_state_pub, &ctrl_state);
				}
			}


			{
				// generate vehicle attitude quaternion data
				struct vehicle_attitude_s att = {};
				att.timestamp = _replay_mode ? now : hrt_absolute_time();

				q.copyTo(att.q);

				att.rollspeed = gyro_rad[0];
				att.pitchspeed = gyro_rad[1];
				att.yawspeed = gyro_rad[2];

				// publish vehicle attitude data
				if (_att_pub == nullptr) {
					_att_pub = orb_advertise(ORB_ID(vehicle_attitude), &att);

				} else {
					orb_publish(ORB_ID(vehicle_attitude), _att_pub, &att);
				}
			}

			// generate vehicle local position data
			struct vehicle_local_position_s lpos = {};
			float pos[3] = {};

			lpos.timestamp = _replay_mode ? now : hrt_absolute_time();

			// Position of body origin in local NED frame
			_ekf.get_position(pos);
			lpos.x = (_ekf.local_position_is_valid()) ? pos[0] : 0.0f;
			lpos.y = (_ekf.local_position_is_valid()) ? pos[1] : 0.0f;
			lpos.z = pos[2];

			// Velocity of body origin in local NED frame (m/s)
			lpos.vx = velocity[0];
			lpos.vy = velocity[1];
			lpos.vz = velocity[2];

			// TODO: better status reporting
			lpos.xy_valid = _ekf.local_position_is_valid();
			lpos.z_valid = true;
			lpos.v_xy_valid = _ekf.local_position_is_valid();
			lpos.v_z_valid = true;

			// Position of local NED origin in GPS / WGS84 frame
			struct map_projection_reference_s ekf_origin = {};
			// true if position (x, y) is valid and has valid global reference (ref_lat, ref_lon)
			_ekf.get_ekf_origin(&lpos.ref_timestamp, &ekf_origin, &lpos.ref_alt);
			lpos.xy_global = _ekf.global_position_is_valid();
			lpos.z_global = true;                                // true if z is valid and has valid global reference (ref_alt)
			lpos.ref_lat = ekf_origin.lat_rad * 180.0 / M_PI; // Reference point latitude in degrees
			lpos.ref_lon = ekf_origin.lon_rad * 180.0 / M_PI; // Reference point longitude in degrees

			// The rotation of the tangent plane vs. geographical north
			matrix::Eulerf euler(q);
			lpos.yaw = euler.psi();

			float terrain_vpos;
			lpos.dist_bottom_valid = _ekf.get_terrain_vert_pos(&terrain_vpos);
			lpos.dist_bottom = terrain_vpos - pos[2]; // Distance to bottom surface (ground) in meters
			lpos.dist_bottom_rate = -velocity[2]; // Distance to bottom surface (ground) change rate
			lpos.surface_bottom_timestamp	= hrt_absolute_time(); // Time when new bottom surface found

			// TODO: uORB definition does not define what these variables are. We have assumed them to be horizontal and vertical 1-std dev accuracy in metres
			Vector3f pos_var, vel_var;
			_ekf.get_pos_var(pos_var);
			_ekf.get_vel_var(vel_var);
			lpos.eph = sqrtf(pos_var(0) + pos_var(1));
			lpos.epv = sqrtf(pos_var(2));

			// get state reset information of position and velocity
			_ekf.get_posD_reset(&lpos.delta_z, &lpos.z_reset_counter);
			_ekf.get_velD_reset(&lpos.delta_vz, &lpos.vz_reset_counter);
			_ekf.get_posNE_reset(&lpos.delta_xy[0], &lpos.xy_reset_counter);
			_ekf.get_velNE_reset(&lpos.delta_vxy[0], &lpos.vxy_reset_counter);

			// publish vehicle local position data
			if (_lpos_pub == nullptr) {
				_lpos_pub = orb_advertise(ORB_ID(vehicle_local_position), &lpos);

			} else {
				orb_publish(ORB_ID(vehicle_local_position), _lpos_pub, &lpos);
			}

			if (_ekf.global_position_is_valid()) {
				// generate and publish global position data
				struct vehicle_global_position_s global_pos = {};

				global_pos.timestamp = _replay_mode ? now : hrt_absolute_time();
				global_pos.time_utc_usec = gps.time_utc_usec; // GPS UTC timestamp in microseconds

				double est_lat, est_lon, lat_pre_reset, lon_pre_reset;
				map_projection_reproject(&ekf_origin, lpos.x, lpos.y, &est_lat, &est_lon);
				global_pos.lat = est_lat; // Latitude in degrees
				global_pos.lon = est_lon; // Longitude in degrees
				map_projection_reproject(&ekf_origin, lpos.x - lpos.delta_xy[0], lpos.y - lpos.delta_xy[1], &lat_pre_reset,
							 &lon_pre_reset);
				global_pos.delta_lat_lon[0] = est_lat - lat_pre_reset;
				global_pos.delta_lat_lon[1] = est_lon - lon_pre_reset;
				global_pos.lat_lon_reset_counter = lpos.xy_reset_counter;

				global_pos.alt = -pos[2] + lpos.ref_alt; // Altitude AMSL in meters
				_ekf.get_posD_reset(&global_pos.delta_alt, &global_pos.alt_reset_counter);
				// global altitude has opposite sign of local down position
				global_pos.delta_alt *= -1.0f;

				global_pos.vel_n = velocity[0]; // Ground north velocity, m/s
				global_pos.vel_e = velocity[1]; // Ground east velocity, m/s
				global_pos.vel_d = velocity[2]; // Ground downside velocity, m/s

				global_pos.yaw = euler.psi(); // Yaw in radians -PI..+PI.

				global_pos.eph = sqrtf(pos_var(0) + pos_var(1));; // Standard deviation of position estimate horizontally
				global_pos.epv = sqrtf(pos_var(2)); // Standard deviation of position vertically

				if (lpos.dist_bottom_valid) {
					global_pos.terrain_alt = lpos.ref_alt - terrain_vpos; // Terrain altitude in m, WGS84
					global_pos.terrain_alt_valid = true; // Terrain altitude estimate is valid

				} else {
					global_pos.terrain_alt = 0.0f; // Terrain altitude in m, WGS84
					global_pos.terrain_alt_valid = false; // Terrain altitude estimate is valid
				}

				// TODO use innovatun consistency check timouts to set this
				global_pos.dead_reckoning = false; // True if this position is estimated through dead-reckoning

				global_pos.pressure_alt = sensors.baro_alt_meter; // Pressure altitude AMSL (m)

				if (_vehicle_global_position_pub == nullptr) {
					_vehicle_global_position_pub = orb_advertise(ORB_ID(vehicle_global_position), &global_pos);

				} else {
					orb_publish(ORB_ID(vehicle_global_position), _vehicle_global_position_pub, &global_pos);
				}
			}

		} else if (_replay_mode) {
			// in replay mode we have to tell the replay module not to wait for an update
			// we do this by publishing an attitude with zero timestamp
			struct vehicle_attitude_s att = {};
			att.timestamp = now;

			if (_att_pub == nullptr) {
				_att_pub = orb_advertise(ORB_ID(vehicle_attitude), &att);

			} else {
				orb_publish(ORB_ID(vehicle_attitude), _att_pub, &att);
			}
		}

		// publish estimator status
		struct estimator_status_s status = {};
		status.timestamp = _replay_mode ? now : hrt_absolute_time();
		_ekf.get_state_delayed(status.states);
		_ekf.get_covariances(status.covariances);
		_ekf.get_gps_check_status(&status.gps_check_fail_flags);
		_ekf.get_control_mode(&status.control_mode_flags);
		_ekf.get_filter_fault_status(&status.filter_fault_flags);
		_ekf.get_innovation_test_status(&status.innovation_check_flags, &status.mag_test_ratio,
						&status.vel_test_ratio, &status.pos_test_ratio,
						&status.hgt_test_ratio, &status.tas_test_ratio,
						&status.hagl_test_ratio);
		bool dead_reckoning;
		_ekf.get_ekf_lpos_accuracy(&status.pos_horiz_accuracy, &status.pos_vert_accuracy, &dead_reckoning);
		_ekf.get_ekf_soln_status(&status.solution_status_flags);
		_ekf.get_imu_vibe_metrics(status.vibe);

		if (_estimator_status_pub == nullptr) {
			_estimator_status_pub = orb_advertise(ORB_ID(estimator_status), &status);

		} else {
			orb_publish(ORB_ID(estimator_status), _estimator_status_pub, &status);
		}

		// Publish wind estimate
		struct wind_estimate_s wind_estimate = {};
		wind_estimate.timestamp = _replay_mode ? now : hrt_absolute_time();
		wind_estimate.windspeed_north = status.states[22];
		wind_estimate.windspeed_east = status.states[23];
		wind_estimate.covariance_north = status.covariances[22];
		wind_estimate.covariance_east = status.covariances[23];

		if (_wind_pub == nullptr) {
			_wind_pub = orb_advertise(ORB_ID(wind_estimate), &wind_estimate);

		} else {
			orb_publish(ORB_ID(wind_estimate), _wind_pub, &wind_estimate);
		}

		// publish estimator innovation data
		{
			struct ekf2_innovations_s innovations = {};
			innovations.timestamp = _replay_mode ? now : hrt_absolute_time();
			_ekf.get_vel_pos_innov(&innovations.vel_pos_innov[0]);
			_ekf.get_mag_innov(&innovations.mag_innov[0]);
			_ekf.get_heading_innov(&innovations.heading_innov);
			_ekf.get_airspeed_innov(&innovations.airspeed_innov);
			_ekf.get_beta_innov(&innovations.beta_innov);
			_ekf.get_flow_innov(&innovations.flow_innov[0]);
			_ekf.get_hagl_innov(&innovations.hagl_innov);

			_ekf.get_vel_pos_innov_var(&innovations.vel_pos_innov_var[0]);
			_ekf.get_mag_innov_var(&innovations.mag_innov_var[0]);
			_ekf.get_heading_innov_var(&innovations.heading_innov_var);
			_ekf.get_airspeed_innov_var(&innovations.airspeed_innov_var);
			_ekf.get_beta_innov_var(&innovations.beta_innov_var);
			_ekf.get_flow_innov_var(&innovations.flow_innov_var[0]);
			_ekf.get_hagl_innov_var(&innovations.hagl_innov_var);

			_ekf.get_output_tracking_error(&innovations.output_tracking_error[0]);

			if (_estimator_innovations_pub == nullptr) {
				_estimator_innovations_pub = orb_advertise(ORB_ID(ekf2_innovations), &innovations);

			} else {
				orb_publish(ORB_ID(ekf2_innovations), _estimator_innovations_pub, &innovations);
			}

		}

		// save the declination to the EKF2_MAG_DECL parameter when a land event is detected
		if ((_params->mag_declination_source & (1 << 1)) && !_prev_landed && vehicle_land_detected.landed) {
			float decl_deg;
			_ekf.copy_mag_decl_deg(&decl_deg);
			_mag_declination_deg.set(decl_deg);
		}

		_prev_landed = vehicle_land_detected.landed;

		// publish ekf2_timestamps (using 0.1 ms relative timestamps)
		{
			ekf2_timestamps_s ekf2_timestamps;
			ekf2_timestamps.timestamp = sensors.timestamp;

			if (gps_updated) {
				// divide individually to get consistent rounding behavior
				ekf2_timestamps.gps_timestamp_rel = (int16_t)((int64_t)gps.timestamp / 100 - (int64_t)ekf2_timestamps.timestamp / 100);

			} else {
				ekf2_timestamps.gps_timestamp_rel = ekf2_timestamps_s::RELATIVE_TIMESTAMP_INVALID;
			}

			if (optical_flow_updated) {
				ekf2_timestamps.optical_flow_timestamp_rel = (int16_t)((int64_t)optical_flow.timestamp / 100 -
						(int64_t)ekf2_timestamps.timestamp / 100);

			} else {
				ekf2_timestamps.optical_flow_timestamp_rel = ekf2_timestamps_s::RELATIVE_TIMESTAMP_INVALID;
			}

			if (range_finder_updated) {
				ekf2_timestamps.distance_sensor_timestamp_rel = (int16_t)((int64_t)range_finder.timestamp / 100 -
						(int64_t)ekf2_timestamps.timestamp / 100);

			} else {
				ekf2_timestamps.distance_sensor_timestamp_rel = ekf2_timestamps_s::RELATIVE_TIMESTAMP_INVALID;
			}

			if (airspeed_updated) {
				ekf2_timestamps.airspeed_timestamp_rel = (int16_t)((int64_t)airspeed.timestamp / 100 -
						(int64_t)ekf2_timestamps.timestamp / 100);

			} else {
				ekf2_timestamps.airspeed_timestamp_rel = ekf2_timestamps_s::RELATIVE_TIMESTAMP_INVALID;
			}

			if (vision_position_updated) {
				ekf2_timestamps.vision_position_timestamp_rel = (int16_t)((int64_t)ev_pos.timestamp / 100 -
						(int64_t)ekf2_timestamps.timestamp / 100);

			} else {
				ekf2_timestamps.vision_position_timestamp_rel = ekf2_timestamps_s::RELATIVE_TIMESTAMP_INVALID;
			}

			if (vision_attitude_updated) {
				ekf2_timestamps.vision_attitude_timestamp_rel = (int16_t)((int64_t)ev_att.timestamp / 100 -
						(int64_t)ekf2_timestamps.timestamp / 100);

			} else {
				ekf2_timestamps.vision_attitude_timestamp_rel = ekf2_timestamps_s::RELATIVE_TIMESTAMP_INVALID;
			}

			if (_ekf2_timestamps_pub == nullptr) {
				_ekf2_timestamps_pub = orb_advertise(ORB_ID(ekf2_timestamps), &ekf2_timestamps);

			} else {
				orb_publish(ORB_ID(ekf2_timestamps), _ekf2_timestamps_pub, &ekf2_timestamps);
			}
		}


		// publish replay message if in replay mode
		bool publish_replay_message = (bool)_param_record_replay_msg.get();

		if (publish_replay_message) {
			struct ekf2_replay_s replay = {};
			replay.timestamp = now;
			replay.gyro_integral_dt = sensors.gyro_integral_dt;
			replay.accelerometer_integral_dt = sensors.accelerometer_integral_dt;
			replay.magnetometer_timestamp = _timestamp_mag_us;
			replay.baro_timestamp = _timestamp_balt_us;
			memcpy(replay.gyro_rad, sensors.gyro_rad, sizeof(replay.gyro_rad));
			memcpy(replay.accelerometer_m_s2, sensors.accelerometer_m_s2, sizeof(replay.accelerometer_m_s2));
			memcpy(replay.magnetometer_ga, sensors.magnetometer_ga, sizeof(replay.magnetometer_ga));
			replay.baro_alt_meter = sensors.baro_alt_meter;

			// only write gps data if we had a gps update.
			if (gps_updated) {
				replay.time_usec = gps.timestamp;
				replay.lat = gps.lat;
				replay.lon = gps.lon;
				replay.alt = gps.alt;
				replay.fix_type = gps.fix_type;
				replay.nsats = gps.satellites_used;
				replay.eph = gps.eph;
				replay.epv = gps.epv;
				replay.sacc = gps.s_variance_m_s;
				replay.vel_m_s = gps.vel_m_s;
				replay.vel_n_m_s = gps.vel_n_m_s;
				replay.vel_e_m_s = gps.vel_e_m_s;
				replay.vel_d_m_s = gps.vel_d_m_s;
				replay.vel_ned_valid = gps.vel_ned_valid;

			} else {
				// this will tell the logging app not to bother logging any gps replay data
				replay.time_usec = 0;
			}

			if (optical_flow_updated) {
				replay.flow_timestamp = optical_flow.timestamp;
				replay.flow_pixel_integral[0] = optical_flow.pixel_flow_x_integral;
				replay.flow_pixel_integral[1] = optical_flow.pixel_flow_y_integral;
				replay.flow_gyro_integral[0] = optical_flow.gyro_x_rate_integral;
				replay.flow_gyro_integral[1] = optical_flow.gyro_y_rate_integral;
				replay.flow_time_integral = optical_flow.integration_timespan;
				replay.flow_quality = optical_flow.quality;

			} else {
				replay.flow_timestamp = 0;
			}

			if (range_finder_updated) {
				replay.rng_timestamp = range_finder.timestamp;
				replay.range_to_ground = range_finder.current_distance;

			} else {
				replay.rng_timestamp = 0;
			}

			if (airspeed_updated) {
				replay.asp_timestamp = airspeed.timestamp;
				replay.indicated_airspeed_m_s = airspeed.indicated_airspeed_m_s;
				replay.true_airspeed_m_s = airspeed.true_airspeed_m_s;

			} else {
				replay.asp_timestamp = 0;
			}

			if (vision_position_updated || vision_attitude_updated) {
				replay.ev_timestamp = vision_position_updated ? ev_pos.timestamp : ev_att.timestamp;
				replay.pos_ev[0] = ev_pos.x;
				replay.pos_ev[1] = ev_pos.y;
				replay.pos_ev[2] = ev_pos.z;
				replay.quat_ev[0] = ev_att.q[0];
				replay.quat_ev[1] = ev_att.q[1];
				replay.quat_ev[2] = ev_att.q[2];
				replay.quat_ev[3] = ev_att.q[3];
				// TODO : switch to covariances from topic later
				replay.pos_err = _default_ev_pos_noise;
				replay.ang_err = _default_ev_ang_noise;

			} else {
				replay.ev_timestamp = 0;
			}

			if (_replay_pub == nullptr) {
				_replay_pub = orb_advertise(ORB_ID(ekf2_replay), &replay);

			} else {
				orb_publish(ORB_ID(ekf2_replay), _replay_pub, &replay);
			}
		}
	}

	orb_unsubscribe(sensors_sub);
	orb_unsubscribe(gps_sub);
	orb_unsubscribe(airspeed_sub);
	orb_unsubscribe(params_sub);
	orb_unsubscribe(optical_flow_sub);
	orb_unsubscribe(range_finder_sub);
	orb_unsubscribe(ev_pos_sub);
	orb_unsubscribe(vehicle_land_detected_sub);
	orb_unsubscribe(status_sub);

	delete ekf2::instance;
	ekf2::instance = nullptr;
}
예제 #2
0
void Ekf2::task_main()
{
	// subscribe to relevant topics
	_sensors_sub = orb_subscribe(ORB_ID(sensor_combined));
	_gps_sub = orb_subscribe(ORB_ID(vehicle_gps_position));
	_airspeed_sub = orb_subscribe(ORB_ID(airspeed));
	_params_sub = orb_subscribe(ORB_ID(parameter_update));
	_optical_flow_sub = orb_subscribe(ORB_ID(optical_flow));
	_range_finder_sub = orb_subscribe(ORB_ID(distance_sensor));
	_ev_pos_sub = orb_subscribe(ORB_ID(vision_position_estimate));
	_vehicle_land_detected_sub = orb_subscribe(ORB_ID(vehicle_land_detected));
	_status_sub = orb_subscribe(ORB_ID(vehicle_status));

	px4_pollfd_struct_t fds[2] = {};
	fds[0].fd = _sensors_sub;
	fds[0].events = POLLIN;
	fds[1].fd = _params_sub;
	fds[1].events = POLLIN;

	// initialise parameter cache
	updateParams();

	// initialize data structures outside of loop
	// because they will else not always be
	// properly populated
	sensor_combined_s sensors = {};
	vehicle_gps_position_s gps = {};
	airspeed_s airspeed = {};
	optical_flow_s optical_flow = {};
	distance_sensor_s range_finder = {};
	vehicle_land_detected_s vehicle_land_detected = {};
	vision_position_estimate_s ev = {};
	vehicle_status_s _vehicle_status = {};

	while (!_task_should_exit) {
		int ret = px4_poll(fds, sizeof(fds) / sizeof(fds[0]), 1000);

		if (ret < 0) {
			// Poll error, sleep and try again
			usleep(10000);
			continue;

		} else if (ret == 0) {
			// Poll timeout or no new data, do nothing
			continue;
		}

		if (fds[1].revents & POLLIN) {
			// read from param to clear updated flag
			struct parameter_update_s update;
			orb_copy(ORB_ID(parameter_update), _params_sub, &update);
			updateParams();

			// fetch sensor data in next loop
			continue;

		} else if (!(fds[0].revents & POLLIN)) {
			// no new data
			continue;
		}

		bool gps_updated = false;
		bool airspeed_updated = false;
		bool optical_flow_updated = false;
		bool range_finder_updated = false;
		bool vehicle_land_detected_updated = false;
		bool vision_position_updated = false;
		bool vehicle_status_updated = false;

		orb_copy(ORB_ID(sensor_combined), _sensors_sub, &sensors);
		// update all other topics if they have new data

		orb_check(_status_sub, &vehicle_status_updated);

		if (vehicle_status_updated) {
			orb_copy(ORB_ID(vehicle_status), _status_sub, &_vehicle_status);
		}

		orb_check(_gps_sub, &gps_updated);

		if (gps_updated) {
			orb_copy(ORB_ID(vehicle_gps_position), _gps_sub, &gps);
		}

		orb_check(_airspeed_sub, &airspeed_updated);

		if (airspeed_updated) {
			orb_copy(ORB_ID(airspeed), _airspeed_sub, &airspeed);
		}

		orb_check(_optical_flow_sub, &optical_flow_updated);

		if (optical_flow_updated) {
			orb_copy(ORB_ID(optical_flow), _optical_flow_sub, &optical_flow);
		}

		orb_check(_range_finder_sub, &range_finder_updated);

		if (range_finder_updated) {
			orb_copy(ORB_ID(distance_sensor), _range_finder_sub, &range_finder);
		}

		orb_check(_ev_pos_sub, &vision_position_updated);

		if (vision_position_updated) {
			orb_copy(ORB_ID(vision_position_estimate), _ev_pos_sub, &ev);
		}

		// in replay mode we are getting the actual timestamp from the sensor topic
		hrt_abstime now = 0;

		if (_replay_mode) {
			now = sensors.timestamp;

		} else {
			now = hrt_absolute_time();
		}

		// push imu data into estimator
		_ekf.setIMUData(now, sensors.gyro_integral_dt[0], sensors.accelerometer_integral_dt[0],
				&sensors.gyro_integral_rad[0], &sensors.accelerometer_integral_m_s[0]);

		// read mag data
		_ekf.setMagData(sensors.magnetometer_timestamp[0], &sensors.magnetometer_ga[0]);

		// read baro data
		_ekf.setBaroData(sensors.baro_timestamp[0], &sensors.baro_alt_meter[0]);

		// read gps data if available
		if (gps_updated) {
			struct gps_message gps_msg = {};
			gps_msg.time_usec = gps.timestamp;
			gps_msg.lat = gps.lat;
			gps_msg.lon = gps.lon;
			gps_msg.alt = gps.alt;
			gps_msg.fix_type = gps.fix_type;
			gps_msg.eph = gps.eph;
			gps_msg.epv = gps.epv;
			gps_msg.sacc = gps.s_variance_m_s;
			gps_msg.vel_m_s = gps.vel_m_s;
			gps_msg.vel_ned[0] = gps.vel_n_m_s;
			gps_msg.vel_ned[1] = gps.vel_e_m_s;
			gps_msg.vel_ned[2] = gps.vel_d_m_s;
			gps_msg.vel_ned_valid = gps.vel_ned_valid;
			gps_msg.nsats = gps.satellites_used;
			//TODO add gdop to gps topic
			gps_msg.gdop = 0.0f;

			_ekf.setGpsData(gps.timestamp, &gps_msg);
		}

		// only set airspeed data if condition for airspeed fusion are met
		bool fuse_airspeed = airspeed_updated && !_vehicle_status.is_rotary_wing
				     && _arspFusionThreshold.get() <= airspeed.true_airspeed_m_s && _arspFusionThreshold.get() >= 0.1f;

		if (fuse_airspeed) {
			float eas2tas = airspeed.true_airspeed_m_s / airspeed.indicated_airspeed_m_s;
			_ekf.setAirspeedData(airspeed.timestamp, &airspeed.true_airspeed_m_s, &eas2tas);
		}

		if (optical_flow_updated) {
			flow_message flow;
			flow.flowdata(0) = optical_flow.pixel_flow_x_integral;
			flow.flowdata(1) = optical_flow.pixel_flow_y_integral;
			flow.quality = optical_flow.quality;
			flow.gyrodata(0) = optical_flow.gyro_x_rate_integral;
			flow.gyrodata(1) = optical_flow.gyro_y_rate_integral;
			flow.gyrodata(2) = optical_flow.gyro_z_rate_integral;
			flow.dt = optical_flow.integration_timespan;

			if (PX4_ISFINITE(optical_flow.pixel_flow_y_integral) &&
			    PX4_ISFINITE(optical_flow.pixel_flow_x_integral)) {
				_ekf.setOpticalFlowData(optical_flow.timestamp, &flow);
			}
		}

		if (range_finder_updated) {
			_ekf.setRangeData(range_finder.timestamp, &range_finder.current_distance);
		}

		// get external vision data
		// if error estimates are unavailable, use parameter defined defaults
		if (vision_position_updated) {
			ext_vision_message ev_data;
			ev_data.posNED(0) = ev.x;
			ev_data.posNED(1) = ev.y;
			ev_data.posNED(2) = ev.z;
			Quaternion q(ev.q);
			ev_data.quat = q;

			// position measurement error
			if (ev.pos_err >= 0.001f) {
				ev_data.posErr = ev.pos_err;

			} else {
				ev_data.posErr = _default_ev_pos_noise;
			}

			// angle measurement error
			if (ev.ang_err >= 0.001f) {
				ev_data.angErr = ev.ang_err;

			} else {
				ev_data.angErr = _default_ev_ang_noise;
			}

			// use timestamp from external computer - requires clocks to be synchronised so may not be a good idea
			_ekf.setExtVisionData(ev.timestamp_computer, &ev_data);
		}

		orb_check(_vehicle_land_detected_sub, &vehicle_land_detected_updated);

		if (vehicle_land_detected_updated) {
			orb_copy(ORB_ID(vehicle_land_detected), _vehicle_land_detected_sub, &vehicle_land_detected);
			_ekf.set_in_air_status(!vehicle_land_detected.landed);
		}

		// run the EKF update and output
		if (_ekf.update()) {
			// generate vehicle attitude quaternion data
			struct vehicle_attitude_s att = {};
			_ekf.copy_quaternion(att.q);
			matrix::Quaternion<float> q(att.q[0], att.q[1], att.q[2], att.q[3]);

			// generate control state data
			control_state_s ctrl_state = {};
			float gyro_bias[3] = {};
			_ekf.get_gyro_bias(gyro_bias);
			ctrl_state.timestamp = hrt_absolute_time();
			ctrl_state.roll_rate = _lp_roll_rate.apply(sensors.gyro_rad_s[0]) - gyro_bias[0];
			ctrl_state.pitch_rate = _lp_pitch_rate.apply(sensors.gyro_rad_s[1]) - gyro_bias[1];
			ctrl_state.yaw_rate = _lp_yaw_rate.apply(sensors.gyro_rad_s[2]) - gyro_bias[2];

			// Velocity in body frame
			float velocity[3];
			_ekf.get_velocity(velocity);
			Vector3f v_n(velocity);
			matrix::Dcm<float> R_to_body(q.inversed());
			Vector3f v_b = R_to_body * v_n;
			ctrl_state.x_vel = v_b(0);
			ctrl_state.y_vel = v_b(1);
			ctrl_state.z_vel = v_b(2);


			// Local Position NED
			float position[3];
			_ekf.get_position(position);
			ctrl_state.x_pos = position[0];
			ctrl_state.y_pos = position[1];
			ctrl_state.z_pos = position[2];

			// Attitude quaternion
			ctrl_state.q[0] = q(0);
			ctrl_state.q[1] = q(1);
			ctrl_state.q[2] = q(2);
			ctrl_state.q[3] = q(3);

			// Acceleration data
			matrix::Vector<float, 3> acceleration = {&sensors.accelerometer_m_s2[0]};

			float accel_bias[3];
			_ekf.get_accel_bias(accel_bias);
			ctrl_state.x_acc = acceleration(0) - accel_bias[0];
			ctrl_state.y_acc = acceleration(1) - accel_bias[1];
			ctrl_state.z_acc = acceleration(2) - accel_bias[2];

			// compute lowpass filtered horizontal acceleration
			acceleration = R_to_body.transpose() * acceleration;
			_acc_hor_filt = 0.95f * _acc_hor_filt + 0.05f * sqrtf(acceleration(0) * acceleration(0) + acceleration(
						1) * acceleration(1));
			ctrl_state.horz_acc_mag = _acc_hor_filt;

			float vel[3] = {};
			_ekf.get_velocity(vel);

			ctrl_state.airspeed_valid = false;

			// use estimated velocity for airspeed estimate
			if (_airspeed_mode.get() == control_state_s::AIRSPD_MODE_MEAS) {
				// use measured airspeed
				if (PX4_ISFINITE(airspeed.indicated_airspeed_m_s) && hrt_absolute_time() - airspeed.timestamp < 1e6
				    && airspeed.timestamp > 0) {
					ctrl_state.airspeed = airspeed.indicated_airspeed_m_s;
					ctrl_state.airspeed_valid = true;
				}

			} else if (_airspeed_mode.get() == control_state_s::AIRSPD_MODE_EST) {
				if (_ekf.local_position_is_valid()) {
					ctrl_state.airspeed = sqrtf(vel[0] * vel[0] + vel[1] * vel[1] + vel[2] * vel[2]);
					ctrl_state.airspeed_valid = true;
				}

			} else if (_airspeed_mode.get() == control_state_s::AIRSPD_MODE_DISABLED) {
				// do nothing, airspeed has been declared as non-valid above, controllers
				// will handle this assuming always trim airspeed
			}

			// publish control state data
			if (_control_state_pub == nullptr) {
				_control_state_pub = orb_advertise(ORB_ID(control_state), &ctrl_state);

			} else {
				orb_publish(ORB_ID(control_state), _control_state_pub, &ctrl_state);
			}


			// generate remaining vehicle attitude data
			att.timestamp = hrt_absolute_time();
			matrix::Euler<float> euler(q);
			att.roll = euler(0);
			att.pitch = euler(1);
			att.yaw = euler(2);

			att.q[0] = q(0);
			att.q[1] = q(1);
			att.q[2] = q(2);
			att.q[3] = q(3);
			att.q_valid = true;

			att.rollspeed = sensors.gyro_rad_s[0];
			att.pitchspeed = sensors.gyro_rad_s[1];
			att.yawspeed = sensors.gyro_rad_s[2];

			// publish vehicle attitude data
			if (_att_pub == nullptr) {
				_att_pub = orb_advertise(ORB_ID(vehicle_attitude), &att);

			} else {
				orb_publish(ORB_ID(vehicle_attitude), _att_pub, &att);
			}

			// generate vehicle local position data
			struct vehicle_local_position_s lpos = {};
			float pos[3] = {};

			lpos.timestamp = hrt_absolute_time();

			// Position of body origin in local NED frame
			_ekf.get_position(pos);
			lpos.x = pos[0];
			lpos.y = pos[1];
			lpos.z = pos[2];

			// Velocity of body origin in local NED frame (m/s)
			lpos.vx = vel[0];
			lpos.vy = vel[1];
			lpos.vz = vel[2];

			// TODO: better status reporting
			lpos.xy_valid = _ekf.local_position_is_valid();
			lpos.z_valid = true;
			lpos.v_xy_valid = _ekf.local_position_is_valid();
			lpos.v_z_valid = true;

			// Position of local NED origin in GPS / WGS84 frame
			struct map_projection_reference_s ekf_origin = {};
			// true if position (x, y) is valid and has valid global reference (ref_lat, ref_lon)
			_ekf.get_ekf_origin(&lpos.ref_timestamp, &ekf_origin, &lpos.ref_alt);
			lpos.xy_global = _ekf.global_position_is_valid();
			lpos.z_global = true;                                // true if z is valid and has valid global reference (ref_alt)
			lpos.ref_lat = ekf_origin.lat_rad * 180.0 / M_PI; // Reference point latitude in degrees
			lpos.ref_lon = ekf_origin.lon_rad * 180.0 / M_PI; // Reference point longitude in degrees

			// The rotation of the tangent plane vs. geographical north
			lpos.yaw = att.yaw;

			float terrain_vpos;
			lpos.dist_bottom_valid = _ekf.get_terrain_vert_pos(&terrain_vpos);
			lpos.dist_bottom = terrain_vpos - pos[2]; // Distance to bottom surface (ground) in meters
			lpos.dist_bottom_rate = -vel[2]; // Distance to bottom surface (ground) change rate
			lpos.surface_bottom_timestamp	= hrt_absolute_time(); // Time when new bottom surface found

			// TODO: uORB definition does not define what these variables are. We have assumed them to be horizontal and vertical 1-std dev accuracy in metres
			Vector3f pos_var, vel_var;
			_ekf.get_pos_var(pos_var);
			_ekf.get_vel_var(vel_var);
			lpos.eph = sqrt(pos_var(0) + pos_var(1));
			lpos.epv = sqrt(pos_var(2));

			// publish vehicle local position data
			if (_lpos_pub == nullptr) {
				_lpos_pub = orb_advertise(ORB_ID(vehicle_local_position), &lpos);

			} else {
				orb_publish(ORB_ID(vehicle_local_position), _lpos_pub, &lpos);
			}

			// generate and publish global position data
			struct vehicle_global_position_s global_pos = {};

			if (_ekf.global_position_is_valid()) {
				global_pos.timestamp = hrt_absolute_time(); // Time of this estimate, in microseconds since system start
				global_pos.time_utc_usec = gps.time_utc_usec; // GPS UTC timestamp in microseconds

				double est_lat, est_lon;
				map_projection_reproject(&ekf_origin, lpos.x, lpos.y, &est_lat, &est_lon);
				global_pos.lat = est_lat; // Latitude in degrees
				global_pos.lon = est_lon; // Longitude in degrees

				global_pos.alt = -pos[2] + lpos.ref_alt; // Altitude AMSL in meters

				global_pos.vel_n = vel[0]; // Ground north velocity, m/s
				global_pos.vel_e = vel[1]; // Ground east velocity, m/s
				global_pos.vel_d = vel[2]; // Ground downside velocity, m/s

				global_pos.yaw = euler(2); // Yaw in radians -PI..+PI.

				global_pos.eph = sqrt(pos_var(0) + pos_var(1));; // Standard deviation of position estimate horizontally
				global_pos.epv = sqrt(pos_var(2)); // Standard deviation of position vertically

				// TODO: implement terrain estimator
				global_pos.terrain_alt = 0.0f; // Terrain altitude in m, WGS84
				global_pos.terrain_alt_valid = false; // Terrain altitude estimate is valid
				// TODO use innovatun consistency check timouts to set this
				global_pos.dead_reckoning = false; // True if this position is estimated through dead-reckoning

				global_pos.pressure_alt = sensors.baro_alt_meter[0]; // Pressure altitude AMSL (m)

				if (_vehicle_global_position_pub == nullptr) {
					_vehicle_global_position_pub = orb_advertise(ORB_ID(vehicle_global_position), &global_pos);

				} else {
					orb_publish(ORB_ID(vehicle_global_position), _vehicle_global_position_pub, &global_pos);
				}
			}

		} else if (_replay_mode) {
			// in replay mode we have to tell the replay module not to wait for an update
			// we do this by publishing an attitude with zero timestamp
			struct vehicle_attitude_s att = {};
			att.timestamp = 0;

			if (_att_pub == nullptr) {
				_att_pub = orb_advertise(ORB_ID(vehicle_attitude), &att);

			} else {
				orb_publish(ORB_ID(vehicle_attitude), _att_pub, &att);
			}
		}

		// publish estimator status
		struct estimator_status_s status = {};
		status.timestamp = hrt_absolute_time();
		_ekf.get_state_delayed(status.states);
		_ekf.get_covariances(status.covariances);
		_ekf.get_gps_check_status(&status.gps_check_fail_flags);
		_ekf.get_control_mode(&status.control_mode_flags);
		_ekf.get_filter_fault_status(&status.filter_fault_flags);

		if (_estimator_status_pub == nullptr) {
			_estimator_status_pub = orb_advertise(ORB_ID(estimator_status), &status);

		} else {
			orb_publish(ORB_ID(estimator_status), _estimator_status_pub, &status);
		}

		// Publish wind estimate
		struct wind_estimate_s wind_estimate = {};
		wind_estimate.timestamp = hrt_absolute_time();
		wind_estimate.windspeed_north = status.states[22];
		wind_estimate.windspeed_east = status.states[23];
		wind_estimate.covariance_north = status.covariances[22];
		wind_estimate.covariance_east = status.covariances[23];

		if (_wind_pub == nullptr) {
			_wind_pub = orb_advertise(ORB_ID(wind_estimate), &wind_estimate);

		} else {
			orb_publish(ORB_ID(wind_estimate), _wind_pub, &wind_estimate);
		}

		// publish estimator innovation data
		struct ekf2_innovations_s innovations = {};
		innovations.timestamp = hrt_absolute_time();
		_ekf.get_vel_pos_innov(&innovations.vel_pos_innov[0]);
		_ekf.get_mag_innov(&innovations.mag_innov[0]);
		_ekf.get_heading_innov(&innovations.heading_innov);
		_ekf.get_airspeed_innov(&innovations.airspeed_innov);
		_ekf.get_flow_innov(&innovations.flow_innov[0]);
		_ekf.get_hagl_innov(&innovations.hagl_innov);

		_ekf.get_vel_pos_innov_var(&innovations.vel_pos_innov_var[0]);
		_ekf.get_mag_innov_var(&innovations.mag_innov_var[0]);
		_ekf.get_heading_innov_var(&innovations.heading_innov_var);
		_ekf.get_airspeed_innov_var(&innovations.airspeed_innov_var);
		_ekf.get_flow_innov_var(&innovations.flow_innov_var[0]);
		_ekf.get_hagl_innov_var(&innovations.hagl_innov_var);

		if (_estimator_innovations_pub == nullptr) {
			_estimator_innovations_pub = orb_advertise(ORB_ID(ekf2_innovations), &innovations);

		} else {
			orb_publish(ORB_ID(ekf2_innovations), _estimator_innovations_pub, &innovations);
		}

		// save the declination to the EKF2_MAG_DECL parameter when a land event is detected
		if ((_params->mag_declination_source & (1 << 1)) && !_prev_landed && vehicle_land_detected.landed) {
			float decl_deg;
			_ekf.copy_mag_decl_deg(&decl_deg);
			_mag_declination_deg.set(decl_deg);
		}

		_prev_landed = vehicle_land_detected.landed;

		// publish replay message if in replay mode
		bool publish_replay_message = (bool)_param_record_replay_msg.get();

		if (publish_replay_message) {
			struct ekf2_replay_s replay = {};
			replay.time_ref = now;
			replay.gyro_integral_dt = sensors.gyro_integral_dt[0];
			replay.accelerometer_integral_dt = sensors.accelerometer_integral_dt[0];
			replay.magnetometer_timestamp = sensors.magnetometer_timestamp[0];
			replay.baro_timestamp = sensors.baro_timestamp[0];
			memcpy(&replay.gyro_integral_rad[0], &sensors.gyro_integral_rad[0], sizeof(replay.gyro_integral_rad));
			memcpy(&replay.accelerometer_integral_m_s[0], &sensors.accelerometer_integral_m_s[0],
			       sizeof(replay.accelerometer_integral_m_s));
			memcpy(&replay.magnetometer_ga[0], &sensors.magnetometer_ga[0], sizeof(replay.magnetometer_ga));
			replay.baro_alt_meter = sensors.baro_alt_meter[0];

			// only write gps data if we had a gps update.
			if (gps_updated) {
				replay.time_usec = gps.timestamp;
				replay.time_usec_vel = gps.timestamp;
				replay.lat = gps.lat;
				replay.lon = gps.lon;
				replay.alt = gps.alt;
				replay.fix_type = gps.fix_type;
				replay.nsats = gps.satellites_used;
				replay.eph = gps.eph;
				replay.epv = gps.epv;
				replay.sacc = gps.s_variance_m_s;
				replay.vel_m_s = gps.vel_m_s;
				replay.vel_n_m_s = gps.vel_n_m_s;
				replay.vel_e_m_s = gps.vel_e_m_s;
				replay.vel_d_m_s = gps.vel_d_m_s;
				replay.vel_ned_valid = gps.vel_ned_valid;

			} else {
				// this will tell the logging app not to bother logging any gps replay data
				replay.time_usec = 0;
			}

			if (optical_flow_updated) {
				replay.flow_timestamp = optical_flow.timestamp;
				replay.flow_pixel_integral[0] = optical_flow.pixel_flow_x_integral;
				replay.flow_pixel_integral[1] = optical_flow.pixel_flow_y_integral;
				replay.flow_gyro_integral[0] = optical_flow.gyro_x_rate_integral;
				replay.flow_gyro_integral[1] = optical_flow.gyro_y_rate_integral;
				replay.flow_time_integral = optical_flow.integration_timespan;
				replay.flow_quality = optical_flow.quality;

			} else {
				replay.flow_timestamp = 0;
			}

			if (range_finder_updated) {
				replay.rng_timestamp = range_finder.timestamp;
				replay.range_to_ground = range_finder.current_distance;

			} else {
				replay.rng_timestamp = 0;
			}

			if (airspeed_updated) {
				replay.asp_timestamp = airspeed.timestamp;
				replay.indicated_airspeed_m_s = airspeed.indicated_airspeed_m_s;
				replay.true_airspeed_m_s = airspeed.true_airspeed_m_s;

			} else {
				replay.asp_timestamp = 0;
			}

			if (vision_position_updated) {
				replay.ev_timestamp = ev.timestamp_computer;
				replay.pos_ev[0] = ev.x;
				replay.pos_ev[1] = ev.y;
				replay.pos_ev[2] = ev.z;
				replay.quat_ev[0] = ev.q[0];
				replay.quat_ev[1] = ev.q[1];
				replay.quat_ev[2] = ev.q[2];
				replay.quat_ev[3] = ev.q[3];
				replay.pos_err = ev.pos_err;
				replay.ang_err = ev.ang_err;

			} else {
				replay.ev_timestamp = 0;
			}

			if (_replay_pub == nullptr) {
				_replay_pub = orb_advertise(ORB_ID(ekf2_replay), &replay);

			} else {
				orb_publish(ORB_ID(ekf2_replay), _replay_pub, &replay);
			}
		}
	}

	delete ekf2::instance;
	ekf2::instance = nullptr;
}