/****************************************************************************
*
* Copyright (C) 2012 PX4 Development Team. All rights reserved.
* Author: 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 multirotor_att_control_main.c
*
* Implementation of multirotor attitude control main loop.
*
* @author Lorenz Meier <lm@inf.ethz.ch>
*/
#include <nuttx/config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <debug.h>
#include <getopt.h>
#include <time.h>
#include <math.h>
#include <poll.h>
#include <sys/prctl.h>
#include <drivers/drv_hrt.h>
#include <uORB/uORB.h>
#include <drivers/drv_gyro.h>
#include <uORB/topics/vehicle_control_mode.h>
#include <uORB/topics/vehicle_attitude.h>
#include <uORB/topics/vehicle_attitude_setpoint.h>
#include <uORB/topics/manual_control_setpoint.h>
#include <uORB/topics/offboard_control_setpoint.h>
#include <uORB/topics/vehicle_rates_setpoint.h>
#include <uORB/topics/sensor_combined.h>
#include <uORB/topics/actuator_controls.h>
#include <uORB/topics/parameter_update.h>
#include <systemlib/perf_counter.h>
#include <systemlib/systemlib.h>
#include <systemlib/param/param.h>
#include "multirotor_attitude_control.h"
#include "multirotor_rate_control.h"
PARAM_DEFINE_FLOAT(MC_RCLOSS_THR, 0.0f); // This defines the throttle when the RC signal is lost.
__EXPORT int multirotor_att_control_main(int argc, char *argv[]);
static bool thread_should_exit;
static int mc_task;
static bool motor_test_mode = false;
static const float min_takeoff_throttle = 0.3f;
static const float yaw_deadzone = 0.01f;
static int
mc_thread_main(int argc, char *argv[])
{
/* declare and safely initialize all structs */
struct vehicle_control_mode_s control_mode;
memset(&control_mode, 0, sizeof(control_mode));
struct vehicle_attitude_s att;
memset(&att, 0, sizeof(att));
struct vehicle_attitude_setpoint_s att_sp;
memset(&att_sp, 0, sizeof(att_sp));
struct manual_control_setpoint_s manual;
memset(&manual, 0, sizeof(manual));
struct sensor_combined_s raw;
memset(&raw, 0, sizeof(raw));
struct offboard_control_setpoint_s offboard_sp;
memset(&offboard_sp, 0, sizeof(offboard_sp));
struct vehicle_rates_setpoint_s rates_sp;
memset(&rates_sp, 0, sizeof(rates_sp));
struct actuator_controls_s actuators;
memset(&actuators, 0, sizeof(actuators));
/* subscribe to attitude, motor setpoints and system state */
int att_sub = orb_subscribe(ORB_ID(vehicle_attitude));
int param_sub = orb_subscribe(ORB_ID(parameter_update));
int att_setpoint_sub = orb_subscribe(ORB_ID(vehicle_attitude_setpoint));
int setpoint_sub = orb_subscribe(ORB_ID(offboard_control_setpoint));
int control_mode_sub = orb_subscribe(ORB_ID(vehicle_control_mode));
int manual_sub = orb_subscribe(ORB_ID(manual_control_setpoint));
int sensor_sub = orb_subscribe(ORB_ID(sensor_combined));
/*
* Do not rate-limit the loop to prevent aliasing
* if rate-limiting would be desired later, the line below would
* enable it.
*
* rate-limit the attitude subscription to 200Hz to pace our loop
* orb_set_interval(att_sub, 5);
*/
struct pollfd fds[2] = {
{ .fd = att_sub, .events = POLLIN },
{ .fd = param_sub, .events = POLLIN }
};
/* publish actuator controls */
for (unsigned i = 0; i < NUM_ACTUATOR_CONTROLS; i++) {
actuators.control[i] = 0.0f;
}
orb_advert_t actuator_pub = orb_advertise(ORB_ID_VEHICLE_ATTITUDE_CONTROLS, &actuators);
orb_advert_t att_sp_pub = orb_advertise(ORB_ID(vehicle_attitude_setpoint), &att_sp);
orb_advert_t rates_sp_pub = orb_advertise(ORB_ID(vehicle_rates_setpoint), &rates_sp);
int rates_sp_sub = orb_subscribe(ORB_ID(vehicle_rates_setpoint));
/* register the perf counter */
perf_counter_t mc_loop_perf = perf_alloc(PC_ELAPSED, "multirotor_att_control_runtime");
perf_counter_t mc_interval_perf = perf_alloc(PC_INTERVAL, "multirotor_att_control_interval");
perf_counter_t mc_err_perf = perf_alloc(PC_COUNT, "multirotor_att_control_err");
/* welcome user */
warnx("starting");
/* store last control mode to detect mode switches */
bool flag_control_manual_enabled = false;
bool flag_control_attitude_enabled = false;
bool control_yaw_position = true;
bool reset_yaw_sp = true;
bool failsafe_first_time = true;
/* prepare the handle for the failsafe throttle */
param_t failsafe_throttle_handle = param_find("MC_RCLOSS_THR");
float failsafe_throttle = 0.0f;
param_get(failsafe_throttle_handle, &failsafe_throttle);
while (!thread_should_exit) {
/* wait for a sensor update, check for exit condition every 500 ms */
int ret = poll(fds, 2, 500);
if (ret < 0) {
/* poll error, count it in perf */
perf_count(mc_err_perf);
} else if (ret == 0) {
/* no return value, ignore */
} 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), param_sub, &update);
/* update parameters */
param_get(failsafe_throttle_handle, &failsafe_throttle);
}
/* only run controller if attitude changed */
if (fds[0].revents & POLLIN) {
perf_begin(mc_loop_perf);
/* get a local copy of system state */
bool updated;
orb_check(control_mode_sub, &updated);
if (updated) {
orb_copy(ORB_ID(vehicle_control_mode), control_mode_sub, &control_mode);
}
/* get a local copy of manual setpoint */
orb_copy(ORB_ID(manual_control_setpoint), manual_sub, &manual);
/* get a local copy of attitude */
orb_copy(ORB_ID(vehicle_attitude), att_sub, &att);
/* get a local copy of attitude setpoint */
orb_copy(ORB_ID(vehicle_attitude_setpoint), att_setpoint_sub, &att_sp);
/* get a local copy of rates setpoint */
orb_check(setpoint_sub, &updated);
if (updated) {
orb_copy(ORB_ID(offboard_control_setpoint), setpoint_sub, &offboard_sp);
}
/* get a local copy of the current sensor values */
orb_copy(ORB_ID(sensor_combined), sensor_sub, &raw);
/* set flag to safe value */
control_yaw_position = true;
/* define which input is the dominating control input */
if (control_mode.flag_control_offboard_enabled) {
/* offboard inputs */
if (offboard_sp.mode == OFFBOARD_CONTROL_MODE_DIRECT_RATES) {
rates_sp.roll = offboard_sp.p1;
rates_sp.pitch = offboard_sp.p2;
rates_sp.yaw = offboard_sp.p3;
rates_sp.thrust = offboard_sp.p4;
rates_sp.timestamp = hrt_absolute_time();
orb_publish(ORB_ID(vehicle_rates_setpoint), rates_sp_pub, &rates_sp);
} else if (offboard_sp.mode == OFFBOARD_CONTROL_MODE_DIRECT_ATTITUDE) {
att_sp.roll_body = offboard_sp.p1;
att_sp.pitch_body = offboard_sp.p2;
att_sp.yaw_body = offboard_sp.p3;
att_sp.thrust = offboard_sp.p4;
att_sp.timestamp = hrt_absolute_time();
/* publish the result to the vehicle actuators */
orb_publish(ORB_ID(vehicle_attitude_setpoint), att_sp_pub, &att_sp);
}
} else if (control_mode.flag_control_manual_enabled) {
/* manual input */
if (control_mode.flag_control_attitude_enabled) {
/* control attitude, update attitude setpoint depending on mode */
/* if the RC signal is lost, try to stay level and go slowly back down to ground */
if (control_mode.failsave_highlevel) {
failsafe_first_time = false;
if (!control_mode.flag_control_velocity_enabled) {
/* don't reset attitude setpoint in position control mode, it's handled by position controller. */
att_sp.roll_body = 0.0f;
att_sp.pitch_body = 0.0f;
}
if (!control_mode.flag_control_climb_rate_enabled) {
/* don't touch throttle in modes with altitude hold, it's handled by position controller.
*
* Only go to failsafe throttle if last known throttle was
* high enough to create some lift to make hovering state likely.
*
* This is to prevent that someone landing, but not disarming his
* multicopter (throttle = 0) does not make it jump up in the air
* if shutting down his remote.
*/
if (isfinite(manual.throttle) && manual.throttle > min_takeoff_throttle) { // TODO use landed status instead of throttle
/* the failsafe throttle is stored as a parameter, as it depends on the copter and the payload */
att_sp.thrust = failsafe_throttle;
} else {
att_sp.thrust = 0.0f;
}
}
/* keep current yaw, do not attempt to go to north orientation,
* since if the pilot regains RC control, he will be lost regarding
* the current orientation.
*/
if (failsafe_first_time) {
reset_yaw_sp = true;
}
} else {
failsafe_first_time = true;
/* control yaw in all manual / assisted modes */
/* set yaw if arming or switching to attitude stabilized mode */
if (!flag_control_manual_enabled || !flag_control_attitude_enabled || !control_mode.flag_armed) {
reset_yaw_sp = true;
}
/* only move setpoint if manual input is != 0 */
// TODO review yaw restpoint reset
if ((manual.yaw < -yaw_deadzone || yaw_deadzone < manual.yaw) && manual.throttle > min_takeoff_throttle) {
/* control yaw rate */
control_yaw_position = false;
rates_sp.yaw = manual.yaw;
reset_yaw_sp = true; // has no effect on control, just for beautiful log
} else {
control_yaw_position = true;
}
if (!control_mode.flag_control_velocity_enabled) {
/* update attitude setpoint if not in position control mode */
att_sp.roll_body = manual.roll;
att_sp.pitch_body = manual.pitch;
if (!control_mode.flag_control_climb_rate_enabled) {
/* pass throttle directly if not in altitude control mode */
att_sp.thrust = manual.throttle;
}
}
}
/* reset yaw setpint to current position if needed */
if (reset_yaw_sp) {
att_sp.yaw_body = att.yaw;
reset_yaw_sp = false;
}
if (motor_test_mode) {
printf("testmode");
att_sp.roll_body = 0.0f;
att_sp.pitch_body = 0.0f;
att_sp.yaw_body = 0.0f;
att_sp.thrust = 0.1f;
}
att_sp.timestamp = hrt_absolute_time();
/* publish the controller output */
orb_publish(ORB_ID(vehicle_attitude_setpoint), att_sp_pub, &att_sp);
} else {
/* manual rate inputs (ACRO), from RC control or joystick */
if (control_mode.flag_control_rates_enabled) {
rates_sp.roll = manual.roll;
rates_sp.pitch = manual.pitch;
rates_sp.yaw = manual.yaw;
rates_sp.thrust = manual.throttle;
rates_sp.timestamp = hrt_absolute_time();
}
}
}
/* check if we should we reset integrals */
bool reset_integral = !control_mode.flag_armed || att_sp.thrust < 0.1f; // TODO use landed status instead of throttle
/* run attitude controller if needed */
if (control_mode.flag_control_attitude_enabled) {
multirotor_control_attitude(&att_sp, &att, &rates_sp, control_yaw_position, reset_integral);
orb_publish(ORB_ID(vehicle_rates_setpoint), rates_sp_pub, &rates_sp);
}
/* measure in what intervals the controller runs */
perf_count(mc_interval_perf);
/* run rates controller if needed */
if (control_mode.flag_control_rates_enabled) {
/* get current rate setpoint */
bool rates_sp_updated = false;
orb_check(rates_sp_sub, &rates_sp_updated);
if (rates_sp_updated) {
orb_copy(ORB_ID(vehicle_rates_setpoint), rates_sp_sub, &rates_sp);
}
/* apply controller */
float rates[3];
rates[0] = att.rollspeed;
rates[1] = att.pitchspeed;
rates[2] = att.yawspeed;
multirotor_control_rates(&rates_sp, rates, &actuators, reset_integral);
} else {
/* rates controller disabled, set actuators to zero for safety */
actuators.control[0] = 0.0f;
actuators.control[1] = 0.0f;
actuators.control[2] = 0.0f;
actuators.control[3] = 0.0f;
}
actuators.timestamp = hrt_absolute_time();
orb_publish(ORB_ID_VEHICLE_ATTITUDE_CONTROLS, actuator_pub, &actuators);
perf_end(mc_loop_perf);
} /* end of poll call for attitude updates */
} /* end of poll return value check */
}
warnx("stopping, disarming motors");
/* kill all outputs */
for (unsigned i = 0; i < NUM_ACTUATOR_CONTROLS; i++)
actuators.control[i] = 0.0f;
orb_publish(ORB_ID_VEHICLE_ATTITUDE_CONTROLS, actuator_pub, &actuators);
close(att_sub);
close(control_mode_sub);
close(manual_sub);
close(actuator_pub);
close(att_sp_pub);
perf_print_counter(mc_loop_perf);
perf_free(mc_loop_perf);
fflush(stdout);
exit(0);
}
static void
usage(const char *reason)
{
if (reason)
fprintf(stderr, "%s\n", reason);
fprintf(stderr, "usage: multirotor_att_control [-m <mode>] [-t] {start|status|stop}\n");
fprintf(stderr, " <mode> is 'rates' or 'attitude'\n");
fprintf(stderr, " -t enables motor test mode with 10%% thrust\n");
exit(1);
}
int multirotor_att_control_main(int argc, char *argv[])
{
int ch;
unsigned int optioncount = 0;
while ((ch = getopt(argc, argv, "tm:")) != EOF) {
switch (ch) {
case 't':
motor_test_mode = true;
optioncount += 1;
break;
case ':':
usage("missing parameter");
break;
default:
fprintf(stderr, "option: -%c\n", ch);
usage("unrecognized option");
break;
}
}
argc -= optioncount;
//argv += optioncount;
if (argc < 1)
usage("missing command");
if (!strcmp(argv[1 + optioncount], "start")) {
thread_should_exit = false;
mc_task = task_spawn_cmd("multirotor_att_control",
SCHED_DEFAULT,
SCHED_PRIORITY_MAX - 15,
2048,
mc_thread_main,
NULL);
exit(0);
}
if (!strcmp(argv[1 + optioncount], "stop")) {
thread_should_exit = true;
exit(0);
}
usage("unrecognized command");
exit(1);
}