void BlockWaypointGuidance::update(vehicle_global_position_s &pos,
vehicle_attitude_s &att,
position_setpoint_s &missionCmd,
position_setpoint_s &lastMissionCmd)
{
// heading to waypoint
float psiTrack = get_bearing_to_next_waypoint(
(double)pos.lat / (double)1e7d,
(double)pos.lon / (double)1e7d,
missionCmd.lat,
missionCmd.lon);
// cross track
struct crosstrack_error_s xtrackError;
get_distance_to_line(&xtrackError,
(double)pos.lat / (double)1e7d,
(double)pos.lon / (double)1e7d,
lastMissionCmd.lat,
lastMissionCmd.lon,
missionCmd.lat,
missionCmd.lon);
_psiCmd = _wrap_2pi(psiTrack -
_xtYawLimit.update(_xt2Yaw.update(xtrackError.distance)));
}
void Navigator::check_traffic()
{
double lat = get_global_position()->lat;
double lon = get_global_position()->lon;
float alt = get_global_position()->alt;
// TODO for non-multirotors predicting the future
// position as accurately as possible will become relevant
// float vel_n = get_global_position()->vel_n;
// float vel_e = get_global_position()->vel_e;
// float vel_d = get_global_position()->vel_d;
bool changed;
orb_check(_traffic_sub, &changed);
float horizontal_separation = 500;
float vertical_separation = 500;
while (changed) {
transponder_report_s tr;
orb_copy(ORB_ID(transponder_report), _traffic_sub, &tr);
uint16_t required_flags = transponder_report_s::PX4_ADSB_FLAGS_VALID_COORDS |
transponder_report_s::PX4_ADSB_FLAGS_VALID_HEADING |
transponder_report_s::PX4_ADSB_FLAGS_VALID_VELOCITY | transponder_report_s::PX4_ADSB_FLAGS_VALID_ALTITUDE;
if ((tr.flags & required_flags) != required_flags) {
orb_check(_traffic_sub, &changed);
continue;
}
float d_hor, d_vert;
get_distance_to_point_global_wgs84(lat, lon, alt,
tr.lat, tr.lon, tr.altitude, &d_hor, &d_vert);
// predict final altitude (positive is up) in prediction time frame
float end_alt = tr.altitude + (d_vert / tr.hor_velocity) * tr.ver_velocity;
// Predict until the vehicle would have passed this system at its current speed
float prediction_distance = d_hor + 1000.0f;
// If the altitude is not getting close to us, do not calculate
// the horizontal separation.
// Since commercial flights do most of the time keep flight levels
// check for the current and for the predicted flight level.
// we also make the implicit assumption that this system is on the lowest
// flight level close to ground in the
// (end_alt - horizontal_separation < alt) condition. If this system should
// ever be used in normal airspace this implementation would anyway be
// inappropriate as it should be replaced with a TCAS compliant solution.
if ((fabsf(alt - tr.altitude) < vertical_separation) || ((end_alt - horizontal_separation) < alt)) {
double end_lat, end_lon;
waypoint_from_heading_and_distance(tr.lat, tr.lon, tr.heading, prediction_distance, &end_lat, &end_lon);
struct crosstrack_error_s cr;
if (!get_distance_to_line(&cr, lat, lon, tr.lat, tr.lon, end_lat, end_lon)) {
if (!cr.past_end && (fabsf(cr.distance) < horizontal_separation)) {
// direction of traffic in human-readable 0..360 degree in earth frame
int traffic_direction = math::degrees(tr.heading) + 180;
switch (_param_traffic_avoidance_mode.get()) {
case 0: {
/* ignore */
PX4_WARN("TRAFFIC %s, hdg: %d", tr.flags & transponder_report_s::PX4_ADSB_FLAGS_VALID_CALLSIGN ? tr.callsign :
"unknown",
traffic_direction);
break;
}
case 1: {
mavlink_log_critical(&_mavlink_log_pub, "WARNING TRAFFIC %s at heading %d, land immediately",
tr.flags & transponder_report_s::PX4_ADSB_FLAGS_VALID_CALLSIGN ? tr.callsign : "unknown",
traffic_direction);
break;
}
case 2: {
mavlink_log_critical(&_mavlink_log_pub, "AVOIDING TRAFFIC %s heading %d, returning home",
tr.flags & transponder_report_s::PX4_ADSB_FLAGS_VALID_CALLSIGN ? tr.callsign : "unknown",
traffic_direction);
// set the return altitude to minimum
_rtl.set_return_alt_min(true);
// ask the commander to execute an RTL
vehicle_command_s vcmd = {};
vcmd.command = vehicle_command_s::VEHICLE_CMD_NAV_RETURN_TO_LAUNCH;
publish_vehicle_cmd(&vcmd);
break;
}
}
}
}
}
orb_check(_traffic_sub, &changed);
}
}
