mirror of https://github.com/ArduPilot/ardupilot
249 lines
6.4 KiB
C++
249 lines
6.4 KiB
C++
/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
|
|
/*
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
/*
|
|
parent class for aircraft simulators
|
|
*/
|
|
|
|
#include <AP_HAL.h>
|
|
#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
|
|
#include <AP_Common.h>
|
|
#include "SIM_Aircraft.h"
|
|
#include <unistd.h>
|
|
#include <sys/time.h>
|
|
#include <stdio.h>
|
|
|
|
/*
|
|
parent class for all simulator types
|
|
*/
|
|
|
|
/*
|
|
constructor
|
|
*/
|
|
Aircraft::Aircraft(const char *home_str, const char *frame_str) :
|
|
ground_level(0),
|
|
frame_height(0),
|
|
dcm(),
|
|
gyro(),
|
|
velocity_ef(),
|
|
mass(0),
|
|
accel_body(0, 0, -GRAVITY_MSS),
|
|
time_now_us(0),
|
|
gyro_noise(radians(0.1f)),
|
|
accel_noise(0.3),
|
|
rate_hz(400)
|
|
{
|
|
char *saveptr=NULL;
|
|
char *s = strdup(home_str);
|
|
char *lat_s = strtok_r(s, ",", &saveptr);
|
|
char *lon_s = strtok_r(NULL, ",", &saveptr);
|
|
char *alt_s = strtok_r(NULL, ",", &saveptr);
|
|
char *yaw_s = strtok_r(NULL, ",", &saveptr);
|
|
|
|
memset(&home, 0, sizeof(home));
|
|
home.lat = atof(lat_s) * 1.0e7;
|
|
home.lng = atof(lon_s) * 1.0e7;
|
|
home.alt = atof(alt_s) * 1.0e2;
|
|
location = home;
|
|
ground_level = home.alt*0.01;
|
|
|
|
dcm.from_euler(0, 0, atof(yaw_s));
|
|
free(s);
|
|
|
|
set_speedup(1);
|
|
}
|
|
|
|
/*
|
|
return true if we are on the ground
|
|
*/
|
|
bool Aircraft::on_ground(const Vector3f &pos) const
|
|
{
|
|
return (-pos.z) + home.alt*0.01f <= ground_level + frame_height;
|
|
}
|
|
|
|
/*
|
|
update location from position
|
|
*/
|
|
void Aircraft::update_position(void)
|
|
{
|
|
float bearing = degrees(atan2f(position.y, position.x));
|
|
float distance = sqrtf(sq(position.x) + sq(position.y));
|
|
|
|
location = home;
|
|
location_update(location, bearing, distance);
|
|
|
|
location.alt = home.alt - position.z*100.0f;
|
|
|
|
time_now_us += frame_time_us;
|
|
sync_frame_time();
|
|
}
|
|
|
|
/*
|
|
rotate to the given yaw
|
|
*/
|
|
void Aircraft::set_yaw_degrees(float yaw_degrees)
|
|
{
|
|
float roll, pitch, yaw;
|
|
dcm.to_euler(&roll, &pitch, &yaw);
|
|
|
|
yaw = radians(yaw_degrees);
|
|
dcm.from_euler(roll, pitch, yaw);
|
|
}
|
|
|
|
/* advance time by deltat in seconds */
|
|
void Aircraft::time_advance(float deltat)
|
|
{
|
|
time_now_us += deltat * 1.0e6f;
|
|
}
|
|
|
|
/* setup the frame step time */
|
|
void Aircraft::setup_frame_time(float new_rate, float new_speedup)
|
|
{
|
|
rate_hz = new_rate;
|
|
target_speedup = new_speedup;
|
|
frame_time_us = 1.0e6f/rate_hz;
|
|
|
|
scaled_frame_time_us = frame_time_us/target_speedup;
|
|
last_wall_time_us = get_wall_time_us();
|
|
achieved_rate_hz = rate_hz;
|
|
}
|
|
|
|
/* adjust frame_time calculation */
|
|
void Aircraft::adjust_frame_time(float new_rate)
|
|
{
|
|
rate_hz = new_rate;
|
|
frame_time_us = 1.0e6f/rate_hz;
|
|
scaled_frame_time_us = frame_time_us/target_speedup;
|
|
}
|
|
|
|
/* try to synchronise simulation time with wall clock time, taking
|
|
into account desired speedup */
|
|
void Aircraft::sync_frame_time(void)
|
|
{
|
|
uint64_t now = get_wall_time_us();
|
|
uint64_t dt_us = now - last_wall_time_us;
|
|
if (dt_us < scaled_frame_time_us) {
|
|
usleep(scaled_frame_time_us - dt_us);
|
|
now = get_wall_time_us();
|
|
|
|
if (now > last_wall_time_us && now - last_wall_time_us < 1.0e5) {
|
|
float rate = 1.0e6f/(now - last_wall_time_us);
|
|
achieved_rate_hz = (0.98f*achieved_rate_hz) + (0.02f*rate);
|
|
if (achieved_rate_hz < rate_hz * target_speedup) {
|
|
scaled_frame_time_us *= 0.999;
|
|
} else {
|
|
scaled_frame_time_us *= 1.001;
|
|
}
|
|
}
|
|
|
|
}
|
|
last_wall_time_us = now;
|
|
}
|
|
|
|
/* add noise based on throttle level (from 0..1) */
|
|
void Aircraft::add_noise(float throttle)
|
|
{
|
|
gyro += Vector3f(rand_normal(0, 1),
|
|
rand_normal(0, 1),
|
|
rand_normal(0, 1)) * gyro_noise * throttle;
|
|
accel_body += Vector3f(rand_normal(0, 1),
|
|
rand_normal(0, 1),
|
|
rand_normal(0, 1)) * accel_noise * throttle;
|
|
}
|
|
|
|
/*
|
|
normal distribution random numbers
|
|
See
|
|
http://en.literateprograms.org/index.php?title=Special:DownloadCode/Box-Muller_transform_%28C%29&oldid=7011
|
|
*/
|
|
double Aircraft::rand_normal(double mean, double stddev)
|
|
{
|
|
static double n2 = 0.0;
|
|
static int n2_cached = 0;
|
|
if (!n2_cached)
|
|
{
|
|
double x, y, r;
|
|
do
|
|
{
|
|
x = 2.0*rand()/RAND_MAX - 1;
|
|
y = 2.0*rand()/RAND_MAX - 1;
|
|
|
|
r = x*x + y*y;
|
|
}
|
|
while (r == 0.0 || r > 1.0);
|
|
{
|
|
double d = sqrt(-2.0*log(r)/r);
|
|
double n1 = x*d;
|
|
n2 = y*d;
|
|
double result = n1*stddev + mean;
|
|
n2_cached = 1;
|
|
return result;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
n2_cached = 0;
|
|
return n2*stddev + mean;
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
fill a sitl_fdm structure from the simulator state
|
|
*/
|
|
void Aircraft::fill_fdm(struct sitl_fdm &fdm) const
|
|
{
|
|
fdm.timestamp_us = time_now_us;
|
|
fdm.latitude = location.lat * 1.0e-7;
|
|
fdm.longitude = location.lng * 1.0e-7;
|
|
fdm.altitude = location.alt * 1.0e-2;
|
|
fdm.heading = degrees(atan2f(velocity_ef.y, velocity_ef.x));
|
|
fdm.speedN = velocity_ef.x;
|
|
fdm.speedE = velocity_ef.y;
|
|
fdm.speedD = velocity_ef.z;
|
|
fdm.xAccel = accel_body.x;
|
|
fdm.yAccel = accel_body.y;
|
|
fdm.zAccel = accel_body.z;
|
|
Vector3f gyro_ef = SITL::convert_earth_frame(dcm, gyro);
|
|
fdm.rollRate = degrees(gyro_ef.x);
|
|
fdm.pitchRate = degrees(gyro_ef.y);
|
|
fdm.yawRate = degrees(gyro_ef.z);
|
|
float r, p, y;
|
|
dcm.to_euler(&r, &p, &y);
|
|
fdm.rollDeg = degrees(r);
|
|
fdm.pitchDeg = degrees(p);
|
|
fdm.yawDeg = degrees(y);
|
|
fdm.airspeed = velocity_ef.length();
|
|
fdm.magic = 0x4c56414f;
|
|
}
|
|
|
|
uint64_t Aircraft::get_wall_time_us() const
|
|
{
|
|
struct timeval tp;
|
|
gettimeofday(&tp,NULL);
|
|
return tp.tv_sec*1.0e6 + tp.tv_usec;
|
|
}
|
|
|
|
/*
|
|
set simulation speedup
|
|
*/
|
|
void Aircraft::set_speedup(float speedup)
|
|
{
|
|
setup_frame_time(rate_hz, speedup);
|
|
}
|
|
#endif // CONFIG_HAL_BOARD
|