ardupilot/AntennaTracker/sensors.cpp

#include "Tracker.h"

/*
  update INS and attitude
 */
void Tracker::update_ahrs()
{
    ahrs.update();
}


/*
  read and update compass
 */
void Tracker::update_compass(void)
{
    if (g.compass_enabled && compass.read()) {
        ahrs.set_compass(&compass);
        if (should_log(MASK_LOG_COMPASS)) {
            DataFlash.Log_Write_Compass();
        }
    }
}

/*
  if the compass is enabled then try to accumulate a reading
 */
void Tracker::compass_accumulate(void)
{
    if (g.compass_enabled) {
        compass.accumulate();
    }    
}

/*
 calibrate compass
*/
void Tracker::compass_cal_update() {
    if (!hal.util->get_soft_armed()) {
        compass.compass_cal_update();
    }
}

/*
    Accel calibration
*/
void Tracker::accel_cal_update() {
    if (hal.util->get_soft_armed()) {
        return;
    }
    ins.acal_update();
    float trim_roll, trim_pitch;
    if (ins.get_new_trim(trim_roll, trim_pitch)) {
        ahrs.set_trim(Vector3f(trim_roll, trim_pitch, 0));
    }
}

/*
  read the GPS
 */
void Tracker::update_GPS(void)
{
    gps.update();

    static uint32_t last_gps_msg_ms;
    static uint8_t ground_start_count = 5;
    if (gps.last_message_time_ms() != last_gps_msg_ms && 
        gps.status() >= AP_GPS::GPS_OK_FIX_3D) {
        last_gps_msg_ms = gps.last_message_time_ms();
        
        if (ground_start_count > 1) {
            ground_start_count--;
        } else if (ground_start_count == 1) {
            // We countdown N number of good GPS fixes
            // so that the altitude is more accurate
            // -------------------------------------
            if (current_loc.lat == 0 && current_loc.lng == 0) {
                ground_start_count = 5;

            } else {
                // Now have an initial GPS position
                // use it as the HOME position in future startups
                current_loc = gps.location();
                set_home(current_loc);

                if (g.compass_enabled) {
                    // Set compass declination automatically
                    compass.set_initial_location(gps.location().lat, gps.location().lng);
                }
                ground_start_count = 0;
            }
        }
    }
}

void Tracker::handle_battery_failsafe(const char* type_str, const int8_t action)
{
    // NOP
    // useful failsafes in the future would include actually recalling the vehicle
    // that is tracked before the tracker loses power to continue tracking it
}