dark0707
/
px4-firmware
forked from Archive/PX4-Autopilot
1
0
Fork 0
Code Pull Requests Activity
px4-firmware/apps/multirotor_pos_control/position_control.c

276 lines
9.7 KiB
C
Raw Blame History

/****************************************************************************
*
* Copyright (C) 2008-2012 PX4 Development Team. All rights reserved.
* Author: @author Lorenz Meier <lm@inf.ethz.ch>
* @author Laurens Mackay <mackayl@student.ethz.ch>
* @author Tobias Naegeli <naegelit@student.ethz.ch>
* @author Martin Rutschmann <rutmarti@student.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_position_control.c
* Implementation of the position control for a multirotor VTOL
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <math.h>
#include <stdbool.h>
#include <float.h>
#include <systemlib/pid/pid.h>
#include "multirotor_position_control.h"
float get_distance_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next)
{
double lat_now_rad = lat_now / 180.0 * M_PI;
double lon_now_rad = lon_now / 180.0 * M_PI;
double lat_next_rad = lat_next / 180.0 * M_PI;
double lon_next_rad = lon_next / 180.0 * M_PI;
double d_lat = lat_next_rad - lat_now_rad;
double d_lon = lon_next_rad - lon_now_rad;
double a = sin(d_lat / 2.0) * sin(d_lat / 2.0) + sin(d_lon / 2.0) * sin(d_lon / 2.0) * cos(lat_now_rad) * cos(lat_next_rad);
double c = 2 * atan2(sqrt(a), sqrt(1 - a));
const double radius_earth = 6371000.0;
return radius_earth * c;
}
float get_bearing_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next)
{
double lat_now_rad = lat_now / 180.0 * M_PI;
double lon_now_rad = lon_now / 180.0 * M_PI;
double lat_next_rad = lat_next / 180.0 * M_PI;
double lon_next_rad = lon_next / 180.0 * M_PI;
double d_lat = lat_next_rad - lat_now_rad;
double d_lon = lon_next_rad - lon_now_rad;
/* conscious mix of double and float trig function to maximize speed and efficiency */
float theta = atan2f(sin(d_lon) * cos(lat_next_rad) , cos(lat_now_rad) * sin(lat_next_rad) - sin(lat_now_rad) * cos(lat_next_rad) * cos(d_lon));
// XXX wrapping check is incomplete
if (theta < 0.0f) {
theta = theta + 2.0f * M_PI_F;
}
return theta;
}
void control_multirotor_position(const struct vehicle_state_s *vstatus, const struct vehicle_manual_control_s *manual,
const struct vehicle_attitude_s *att, const struct vehicle_local_position_s *local_pos,
const struct vehicle_local_position_setpoint_s *local_pos_sp, struct vehicle_attitude_setpoint_s *att_sp)
{
static PID_t distance_controller;
static int read_ret;
static global_data_position_t position_estimated;
static uint16_t counter;
static bool initialized;
static uint16_t pm_counter;
static float lat_next;
static float lon_next;
static float pitch_current;
static float thrust_total;
if (initialized == false) {
pid_init(&distance_controller,
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_P],
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_I],
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_D],
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_AWU],
PID_MODE_DERIVATIV_CALC, 150);//150
// pid_pos_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_LIM];
// pid_pos_z_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_Z_LIM];
thrust_total = 0.0f;
/* Position initialization */
/* Wait for new position estimate */
do {
read_ret = read_lock_position(&position_estimated);
} while (read_ret != 0);
lat_next = position_estimated.lat;
lon_next = position_estimated.lon;
/* attitude initialization */
global_data_lock(&global_data_attitude->access_conf);
pitch_current = global_data_attitude->pitch;
global_data_unlock(&global_data_attitude->access_conf);
initialized = true;
}
/* load new parameters with 10Hz */
if (counter % 50 == 0) {
if (global_data_trylock(&global_data_parameter_storage->access_conf) == 0) {
/* check whether new parameters are available */
if (global_data_parameter_storage->counter > pm_counter) {
pid_set_parameters(&distance_controller,
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_P],
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_I],
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_D],
global_data_parameter_storage->pm.param_values[PARAM_PID_POS_AWU]);
//
// pid_pos_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_LIM];
// pid_pos_z_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_Z_LIM];
pm_counter = global_data_parameter_storage->counter;
printf("Position controller changed pid parameters\n");
}
}
global_data_unlock(&global_data_parameter_storage->access_conf);
}
/* Wait for new position estimate */
do {
read_ret = read_lock_position(&position_estimated);
} while (read_ret != 0);
/* Get next waypoint */ //TODO: add local copy
if (0 == global_data_trylock(&global_data_position_setpoint->access_conf)) {
lat_next = global_data_position_setpoint->x;
lon_next = global_data_position_setpoint->y;
global_data_unlock(&global_data_position_setpoint->access_conf);
}
/* Get distance to waypoint */
float distance_to_waypoint = get_distance_to_next_waypoint(position_estimated.lat , position_estimated.lon, lat_next, lon_next);
// if(counter % 5 == 0)
// printf("distance_to_waypoint: %.4f\n", distance_to_waypoint);
/* Get bearing to waypoint (direction on earth surface to next waypoint) */
float bearing = get_bearing_to_next_waypoint(position_estimated.lat, position_estimated.lon, lat_next, lon_next);
if (counter % 5 == 0)
printf("bearing: %.4f\n", bearing);
/* Calculate speed in direction of bearing (needed for controller) */
float speed_norm = sqrtf(position_estimated.vx * position_estimated.vx + position_estimated.vy * position_estimated.vy);
// if(counter % 5 == 0)
// printf("speed_norm: %.4f\n", speed_norm);
float speed_to_waypoint = 0; //(position_estimated.vx * cosf(bearing) + position_estimated.vy * sinf(bearing))/speed_norm; //FIXME, TODO: re-enable this once we have a full estimate of the speed, then we can do a PID for the distance controller
/* Control Thrust in bearing direction */
float horizontal_thrust = -pid_calculate(&distance_controller, 0, distance_to_waypoint, speed_to_waypoint,
CONTROL_PID_POSITION_INTERVAL); //TODO: maybe this "-" sign is an error somewhere else
// if(counter % 5 == 0)
// printf("horizontal thrust: %.4f\n", horizontal_thrust);
/* Get total thrust (from remote for now) */
if (0 == global_data_trylock(&global_data_rc_channels->access_conf)) {
thrust_total = (float)global_data_rc_channels->chan[THROTTLE].scale; //TODO: how should we use the RC_CHANNELS_FUNCTION enum?
global_data_unlock(&global_data_rc_channels->access_conf);
}
const float max_gas = 500.0f;
thrust_total *= max_gas / 20000.0f; //TODO: check this
thrust_total += max_gas / 2.0f;
if (horizontal_thrust > thrust_total) {
horizontal_thrust = thrust_total;
} else if (horizontal_thrust < -thrust_total) {
horizontal_thrust = -thrust_total;
}
//TODO: maybe we want to add a speed controller later...
/* Calclulate thrust in east and north direction */
float thrust_north = cosf(bearing) * horizontal_thrust;
float thrust_east = sinf(bearing) * horizontal_thrust;
if (counter % 10 == 0) {
printf("thrust north: %.4f\n", thrust_north);
printf("thrust east: %.4f\n", thrust_east);
fflush(stdout);
}
/* Get current attitude */
if (0 == global_data_trylock(&global_data_attitude->access_conf)) {
pitch_current = global_data_attitude->pitch;
global_data_unlock(&global_data_attitude->access_conf);
}
/* Get desired pitch & roll */
float pitch_desired = 0.0f;
float roll_desired = 0.0f;
if (thrust_total != 0) {
float pitch_fraction = -thrust_north / thrust_total;
float roll_fraction = thrust_east / (cosf(pitch_current) * thrust_total);
if (roll_fraction < -1) {
roll_fraction = -1;
} else if (roll_fraction > 1) {
roll_fraction = 1;
}
// if(counter % 5 == 0)
// {
// printf("pitch_fraction: %.4f, roll_fraction: %.4f\n",pitch_fraction, roll_fraction);
// fflush(stdout);
// }
pitch_desired = asinf(pitch_fraction);
roll_desired = asinf(roll_fraction);
}
att_sp.roll = roll_desired;
att_sp.pitch = pitch_desired;
counter++;
}
View Git Blame Copy Permalink