ardupilot/libraries/AP_HAL_AVR_SITL/sitl_barometer.cpp

58 lines
983 B
C++

/*
SITL handling
This simulates a barometer
Andrew Tridgell November 2011
*/
#include <AP_HAL.h>
#if CONFIG_HAL_BOARD == HAL_BOARD_AVR_SITL
#include "HAL_AVR.h"
#include "AP_HAL_AVR_SITL.h"
using namespace AVR_SITL;
extern const AP_HAL::HAL& hal;
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <math.h>
/*
setup the barometer with new input
altitude is in meters
*/
void SITL_State::_update_barometer(float altitude)
{
double Temp, Press, y;
static uint32_t last_update;
if (_barometer == NULL) {
// this sketch doesn't use a barometer
return;
}
// 80Hz, to match the real APM2 barometer
if (hal.scheduler->millis() - last_update < 12) {
return;
}
last_update = hal.scheduler->millis();
Temp = 312;
y = ((altitude-584.0) * 1000.0) / 29271.267;
y /= (Temp / 10.0) + 273.15;
y = 1.0/exp(y);
y *= 95446.0;
Press = y + (_rand_float() * _sitl->baro_noise);
_barometer->setHIL(Temp, Press);
}
#endif