/****************************************************************************
*
* Copyright (C) 2012 PX4 Development Team. All rights reserved.
* Author: Tobias Naegeli <naegelit@student.ethz.ch>
* Lorenz Meier <lm@inf.ethz.ch>
*
* 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
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/*
* @file attitude_estimator_ekf_main.c
*
* Extended Kalman Filter for Attitude Estimation.
*/
#include <nuttx/config.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <poll.h>
#include <fcntl.h>
#include <v1.0/common/mavlink.h>
#include <float.h>
#include <nuttx/sched.h>
#include <sys/prctl.h>
#include <termios.h>
#include <errno.h>
#include <limits.h>
#include <math.h>
#include <uORB/uORB.h>
#include <uORB/topics/debug_key_value.h>
#include <uORB/topics/sensor_combined.h>
#include <uORB/topics/vehicle_attitude.h>
#include <uORB/topics/parameter_update.h>
#include <arch/board/up_hrt.h>
#include <systemlib/systemlib.h>
#include "codegen/attitudeKalmanfilter_initialize.h"
#include "codegen/attitudeKalmanfilter.h"
#include "attitude_estimator_ekf_params.h"
__EXPORT int attitude_estimator_ekf_main(int argc, char *argv[]);
static unsigned int loop_interval_alarm = 6500; // loop interval in microseconds
static float dt = 1.0f;
/* state vector x has the following entries [ax,ay,az||mx,my,mz||wox,woy,woz||wx,wy,wz]' */
static float z_k[9]; /**< Measurement vector */
static float x_aposteriori_k[12]; /**< */
static float x_aposteriori[12];
static float P_aposteriori_k[144] = {100.f, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 100.f, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 100.f, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 100.f, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 100.f, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 100.f, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 100.f, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 100.f, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 100.f, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0.0f, 100.0f, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0.0f, 0, 100.0f, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0.0f, 0, 0, 100.0f,
};
static float P_aposteriori[144] = {100.f, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 100.f, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 100.f, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 100.f, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 100.f, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 100.f, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 100.f, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 100.f, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 100.f, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0.0f, 100.0f, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0.0f, 0, 100.0f, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0.0f, 0, 0, 100.0f,
}; /**< init: diagonal matrix with big values */
/* output euler angles */
static float euler[3] = {0.0f, 0.0f, 0.0f};
static float Rot_matrix[9] = {1.f, 0, 0,
0, 1.f, 0,
0, 0, 1.f
}; /**< init: identity matrix */
static bool thread_should_exit = false; /**< Deamon exit flag */
static bool thread_running = false; /**< Deamon status flag */
static int attitude_estimator_ekf_task; /**< Handle of deamon task / thread */
/**
* Mainloop of attitude_estimator_ekf.
*/
int attitude_estimator_ekf_thread_main(int argc, char *argv[]);
/**
* Print the correct usage.
*/
static void usage(const char *reason);
static void
usage(const char *reason)
{
if (reason)
fprintf(stderr, "%s\n", reason);
fprintf(stderr, "usage: attitude_estimator_ekf {start|stop|status} [-p <additional params>]\n\n");
exit(1);
}
/**
* The attitude_estimator_ekf app only briefly exists to start
* the background job. The stack size assigned in the
* Makefile does only apply to this management task.
*
* The actual stack size should be set in the call
* to task_create().
*/
int attitude_estimator_ekf_main(int argc, char *argv[])
{
if (argc < 1)
usage("missing command");
if (!strcmp(argv[1], "start")) {
if (thread_running) {
printf("attitude_estimator_ekf already running\n");
/* this is not an error */
exit(0);
}
thread_should_exit = false;
attitude_estimator_ekf_task = task_spawn("attitude_estimator_ekf",
SCHED_RR,
SCHED_PRIORITY_MAX - 5,
20000,
attitude_estimator_ekf_thread_main,
(argv) ? (const char **)&argv[2] : (const char **)NULL);
exit(0);
}
if (!strcmp(argv[1], "stop")) {
thread_should_exit = true;
exit(0);
}
if (!strcmp(argv[1], "status")) {
if (thread_running) {
printf("\tattitude_estimator_ekf app is running\n");
} else {
printf("\tattitude_estimator_ekf app not started\n");
}
exit(0);
}
usage("unrecognized command");
exit(1);
}
/*
* [Rot_matrix,x_aposteriori,P_aposteriori] = attitudeKalmanfilter(dt,z_k,x_aposteriori_k,P_aposteriori_k,knownConst)
*/
/*
* EKF Attitude Estimator main function.
*
* Estimates the attitude recursively once started.
*
* @param argc number of commandline arguments (plus command name)
* @param argv strings containing the arguments
*/
int attitude_estimator_ekf_thread_main(int argc, char *argv[])
{
// print text
printf("Extended Kalman Filter Attitude Estimator initialized..\n\n");
fflush(stdout);
int overloadcounter = 19;
/* Initialize filter */
attitudeKalmanfilter_initialize();
/* store start time to guard against too slow update rates */
uint64_t last_run = hrt_absolute_time();
struct sensor_combined_s raw;
struct vehicle_attitude_s att;
uint64_t last_data = 0;
uint64_t last_measurement = 0;
/* subscribe to raw data */
int sub_raw = orb_subscribe(ORB_ID(sensor_combined));
/* rate-limit raw data updates to 200Hz */
orb_set_interval(sub_raw, 4);
/* subscribe to param changes */
int sub_params = orb_subscribe(ORB_ID(parameter_update));
/* advertise attitude */
orb_advert_t pub_att = orb_advertise(ORB_ID(vehicle_attitude), &att);
int loopcounter = 0;
int printcounter = 0;
thread_running = true;
/* advertise debug value */
struct debug_key_value_s dbg = { .key = "", .value = 0.0f };
orb_advert_t pub_dbg = orb_advertise(ORB_ID(debug_key_value), &dbg);
/* keep track of sensor updates */
uint32_t sensor_last_count[3] = {0, 0, 0};
uint64_t sensor_last_timestamp[3] = {0, 0, 0};
float sensor_update_hz[3] = {0.0f, 0.0f, 0.0f};
struct attitude_estimator_ekf_params ekf_params;
struct attitude_estimator_ekf_param_handles ekf_param_handles;
/* initialize parameter handles */
parameters_init(&ekf_param_handles);
/* Main loop*/
while (!thread_should_exit) {
struct pollfd fds[2] = {
{ .fd = sub_raw, .events = POLLIN },
{ .fd = sub_params, .events = POLLIN }
};
int ret = poll(fds, 1, 1000);
if (ret < 0) {
/* XXX this is seriously bad - should be an emergency */
} else if (ret == 0) {
/* XXX this means no sensor data - should be critical or emergency */
printf("[attitude estimator ekf] WARNING: Not getting sensor data - sensor app running?\n");
} else {
/* only update parameters if they changed */
if (fds[1].revents & POLLIN) {
/* read from param to clear updated flag */
struct parameter_update_s update;
orb_copy(ORB_ID(parameter_update), sub_params, &update);
/* update parameters */
parameters_update(&ekf_param_handles, &ekf_params);
}
/* only run filter if sensor values changed */
if (fds[0].revents & POLLIN) {
/* get latest measurements */
orb_copy(ORB_ID(sensor_combined), sub_raw, &raw);
/* Calculate data time difference in seconds */
dt = (raw.timestamp - last_measurement) / 1000000.0f;
last_measurement = raw.timestamp;
uint8_t update_vect[3] = {0, 0, 0};
/* Fill in gyro measurements */
if (sensor_last_count[0] != raw.gyro_counter) {
update_vect[0] = 1;
sensor_last_count[0] = raw.gyro_counter;
sensor_update_hz[0] = 1e6f / (raw.timestamp - sensor_last_timestamp[0]);
sensor_last_timestamp[0] = raw.timestamp;
}
z_k[0] = raw.gyro_rad_s[0];
z_k[1] = raw.gyro_rad_s[1];
z_k[2] = raw.gyro_rad_s[2];
/* update accelerometer measurements */
if (sensor_last_count[1] != raw.accelerometer_counter) {
update_vect[1] = 1;
sensor_last_count[1] = raw.accelerometer_counter;
sensor_update_hz[1] = 1e6f / (raw.timestamp - sensor_last_timestamp[1]);
sensor_last_timestamp[1] = raw.timestamp;
}
z_k[3] = raw.accelerometer_m_s2[0];
z_k[4] = raw.accelerometer_m_s2[1];
z_k[5] = raw.accelerometer_m_s2[2];
/* update magnetometer measurements */
if (sensor_last_count[2] != raw.magnetometer_counter) {
update_vect[2] = 1;
sensor_last_count[2] = raw.magnetometer_counter;
sensor_update_hz[2] = 1e6f / (raw.timestamp - sensor_last_timestamp[2]);
sensor_last_timestamp[2] = raw.timestamp;
}
z_k[6] = raw.magnetometer_ga[0];
z_k[7] = raw.magnetometer_ga[1];
z_k[8] = raw.magnetometer_ga[2];
uint64_t now = hrt_absolute_time();
unsigned int time_elapsed = now - last_run;
last_run = now;
if (time_elapsed > loop_interval_alarm) {
//TODO: add warning, cpu overload here
// if (overloadcounter == 20) {
// printf("CPU OVERLOAD DETECTED IN ATTITUDE ESTIMATOR EKF (%lu > %lu)\n", time_elapsed, loop_interval_alarm);
// overloadcounter = 0;
// }
overloadcounter++;
}
int32_t z_k_sizes = 9;
// float u[4] = {0.0f, 0.0f, 0.0f, 0.0f};
static bool const_initialized = false;
/* initialize with good values once we have a reasonable dt estimate */
if (!const_initialized /*&& dt < 0.05 && dt > 0.005*/)
{
dt = 0.005f;
parameters_update(&ekf_param_handles, &ekf_params);
x_aposteriori_k[0] = z_k[0];
x_aposteriori_k[1] = z_k[1];
x_aposteriori_k[2] = z_k[2];
x_aposteriori_k[3] = 0.0f;
x_aposteriori_k[4] = 0.0f;
x_aposteriori_k[5] = 0.0f;
x_aposteriori_k[6] = z_k[3];
x_aposteriori_k[7] = z_k[4];
x_aposteriori_k[8] = z_k[5];
x_aposteriori_k[9] = z_k[6];
x_aposteriori_k[10] = z_k[7];
x_aposteriori_k[11] = z_k[8];
const_initialized = true;
}
/* do not execute the filter if not initialized */
if (!const_initialized) {
continue;
}
dt = 0.004f;
uint64_t timing_start = hrt_absolute_time();
// attitudeKalmanfilter(dt, update_vect, z_k, &z_k_sizes, u, x_aposteriori_k, P_aposteriori_k, knownConst, euler,
// Rot_matrix, x_aposteriori, P_aposteriori);
attitudeKalmanfilter(update_vect, dt, z_k, x_aposteriori_k, P_aposteriori_k, ekf_params.q, ekf_params.r,
euler, Rot_matrix, x_aposteriori, P_aposteriori);
/* swap values for next iteration */
memcpy(P_aposteriori_k, P_aposteriori, sizeof(P_aposteriori_k));
memcpy(x_aposteriori_k, x_aposteriori, sizeof(x_aposteriori_k));
uint64_t timing_diff = hrt_absolute_time() - timing_start;
// /* print rotation matrix every 200th time */
if (printcounter % 200 == 0) {
// printf("x apo:\n%8.4f\t%8.4f\t%8.4f\n%8.4f\t%8.4f\t%8.4f\n%8.4f\t%8.4f\t%8.4f\n",
// x_aposteriori[0], x_aposteriori[1], x_aposteriori[2],
// x_aposteriori[3], x_aposteriori[4], x_aposteriori[5],
// x_aposteriori[6], x_aposteriori[7], x_aposteriori[8]);
// }
printf("EKF attitude iteration: %d, runtime: %d us, dt: %d us (%d Hz)\n", loopcounter, (int)timing_diff, (int)(dt * 1000000.0f), (int)(1.0f / dt));
printf("roll: %8.4f\tpitch: %8.4f\tyaw:%8.4f\n", (double)euler[0], (double)euler[1], (double)euler[2]);
printf("update rates gyro: %8.4f\taccel: %8.4f\tmag:%8.4f\n", (double)sensor_update_hz[0], (double)sensor_update_hz[1], (double)sensor_update_hz[2]);
// printf("\n%d\t%d\t%d\n%d\t%d\t%d\n%d\t%d\t%d\n", (int)(Rot_matrix[0] * 100), (int)(Rot_matrix[1] * 100), (int)(Rot_matrix[2] * 100),
// (int)(Rot_matrix[3] * 100), (int)(Rot_matrix[4] * 100), (int)(Rot_matrix[5] * 100),
// (int)(Rot_matrix[6] * 100), (int)(Rot_matrix[7] * 100), (int)(Rot_matrix[8] * 100));
}
// int i = printcounter % 9;
// // for (int i = 0; i < 9; i++) {
// char name[10];
// sprintf(name, "xapo #%d", i);
// memcpy(dbg.key, name, sizeof(dbg.key));
// dbg.value = x_aposteriori[i];
// orb_publish(ORB_ID(debug_key_value), pub_dbg, &dbg);
printcounter++;
if (last_data > 0 && raw.timestamp - last_data > 12000) printf("[attitude estimator ekf] sensor data missed! (%llu)\n", raw.timestamp - last_data);
last_data = raw.timestamp;
/* send out */
att.timestamp = raw.timestamp;
att.roll = euler[0];
att.pitch = euler[1];
att.yaw = euler[2];
att.rollspeed = x_aposteriori[0];
att.pitchspeed = x_aposteriori[1];
att.yawspeed = x_aposteriori[2];
/* copy offsets */
memcpy(&att.rate_offsets, &(x_aposteriori[3]), sizeof(att.rate_offsets));
/* copy rotation matrix */
memcpy(&att.R, Rot_matrix, sizeof(Rot_matrix));
att.R_valid = true;
// Broadcast
orb_publish(ORB_ID(vehicle_attitude), pub_att, &att);
}
}
loopcounter++;
}
thread_running = false;
return 0;
}