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Roy Vegard Ovesen:

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I've added a tracking bug to the gps. This is of course very similar to a
heading bug for a DG. I don't know if this is the common name, but I feel
that for a gps the name tracking bug is more accurate than heading bug. A
true bug error and a magnetic bug error is calculated and shifted into the
-180 to 180 range so that they can be used by autopilots.

I've also fixed a property name that crept in when I had to change back to
indicated-***. Back then I accidentally changed the desired course name to
"indicated-course". The property that is supposed to be the input for the
desired course should naturally be named something like "desired-course", and
definitely _not_ "indicated-course". If this name change breaks anything it
should be fixed in the other end.

I've also commented out a lot of #includes that I don't think is needed. I'm
on Suse 9.0 now, and it builds fine here, but this might be a problem for
different platforms    I guess we have to cross our fingers.
This commit is contained in:
curt 2004-04-16 22:12:26 +00:00
parent 994f4a16c4
commit 4a41f96631
2 changed files with 68 additions and 25 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

76
src/Instrumentation/gps.cxx
View file

@ -9,24 +9,10 @@
#include <simgear/compiler.h>
#include <string.h>
#include STL_STRING
#include <Aircraft/aircraft.hxx>
#include <FDM/flight.hxx>
#include <Controls/controls.hxx>
#include <Scenery/scenery.hxx>
#include <simgear/constants.h>
#include <simgear/sg_inlines.h>
#include <simgear/debug/logstream.hxx>
#include <simgear/math/sg_geodesy.hxx>
#include <simgear/misc/sg_path.hxx>
#include <simgear/route/route.hxx>
#include <Airports/simple.hxx>
#include <GUI/gui.h>
#include <Main/fg_init.hxx>
#include <Main/globals.hxx>
#include <Main/fg_props.hxx>
@ -70,11 +56,13 @@ GPS::init ()
_wp_name_node =
fgGetNode("/instrumentation/gps/wp-name", true);
_wp_course_node =
fgGetNode("/instrumentation/gps/indicated-course-deg", true);
fgGetNode("/instrumentation/gps/desired-course-deg", true);
_get_nearest_airport_node =
fgGetNode("/instrumentation/gps/get-nearest-airport", true);
fgGetNode("/instrumentation/gps/get-nearest-airport", true);
_waypoint_type_node =
fgGetNode("/instrumentation/gps/waypoint-type", true);
fgGetNode("/instrumentation/gps/waypoint-type", true);
_tracking_bug_node =
fgGetNode("/instrumentation/gps/tracking-bug", true);
_raim_node = fgGetNode("/instrumentation/gps/raim", true);
_indicated_longitude_node =
@ -95,6 +83,8 @@ GPS::init ()
fgGetNode("/instrumentation/gps/TTW",true);
_wp_bearing_node =
fgGetNode("/instrumentation/gps/wp-bearing-deg", true);
_wp_mag_bearing_node =
fgGetNode("/instrumentation/gps/wp-bearing-mag-deg", true);
_wp_course_deviation_node =
fgGetNode("/instrumentation/gps/course-deviation-deg", true);
_wp_course_error_nm_node =
@ -104,7 +94,12 @@ GPS::init ()
_odometer_node =
fgGetNode("/instrumentation/gps/odometer", true);
_trip_odometer_node =
fgGetNode("/instrumentation/gps/trip-odometer", true);
fgGetNode("/instrumentation/gps/trip-odometer", true);
_true_bug_error_node =
fgGetNode("/instrumentation/gps/true-bug-error-deg", true);
_magnetic_bug_error_node =
fgGetNode("/instrumentation/gps/magnetic-bug-error-deg", true);
}
void
@ -132,10 +127,14 @@ GPS::update (double delta_time_sec)
_wp_course_node->setDoubleValue(0);
_odometer_node->setDoubleValue(0);
_trip_odometer_node->setDoubleValue(0);
_tracking_bug_node->setDoubleValue(0);
_true_bug_error_node->setDoubleValue(0);
_magnetic_bug_error_node->setDoubleValue(0);
return;
}
// Get the aircraft position
// Get the aircraft position
// TODO: Add noise and other errors.
double longitude_deg = _longitude_node->getDoubleValue();
double latitude_deg = _latitude_node->getDoubleValue();
double altitude_m = _altitude_node->getDoubleValue() * SG_FEET_TO_METER;
@ -149,7 +148,7 @@ GPS::update (double delta_time_sec)
_indicated_altitude_node->setDoubleValue(altitude_m * SG_METER_TO_FEET);
if (_last_valid) {
double track1_deg, track2_deg, distance_m, odometer;
double track1_deg, track2_deg, distance_m, odometer, mag_track_bearing;
geo_inverse_wgs_84(altitude_m,
_last_latitude_deg, _last_longitude_deg,
latitude_deg, longitude_deg,
@ -157,7 +156,8 @@ GPS::update (double delta_time_sec)
speed_kt = ((distance_m * SG_METER_TO_NM) *
((1 / delta_time_sec) * 3600.0));
_true_track_node->setDoubleValue(track1_deg);
_magnetic_track_node->setDoubleValue(track1_deg - magvar_deg);
mag_track_bearing = deg360(track1_deg - magvar_deg);
_magnetic_track_node->setDoubleValue(mag_track_bearing);
speed_kt = fgGetLowPass(_last_speed_kts, speed_kt, delta_time_sec/20.0);
_last_speed_kts = speed_kt;
_speed_node->setDoubleValue(speed_kt);
@ -174,7 +174,6 @@ GPS::update (double delta_time_sec)
_wp_course_node->getDoubleValue();
double wp_distance, wp_bearing_deg, wp_course_deviation_deg,
wp_course_error_m, wp_TTW;
// double wp_actual_radial_deg;
string wp_ID = _wp_ID_node->getStringValue();
// If the get-nearest-airport-node is true.
@ -237,6 +236,7 @@ GPS::update (double delta_time_sec)
_wp_latitude_node->setDoubleValue(wp_latitude_deg);
_wp_distance_node->setDoubleValue(wp_distance * SG_METER_TO_NM);
_wp_bearing_node->setDoubleValue(wp_bearing_deg);
_wp_mag_bearing_node->setDoubleValue(deg360(wp_bearing_deg - magvar_deg));
// Estimate time to waypoint.
// The estimation does not take track into consideration,
@ -302,6 +302,25 @@ GPS::update (double delta_time_sec)
_wp_course_error_nm_node->setDoubleValue(wp_course_error_m
* SG_METER_TO_NM);
// Tracking bug.
double tracking_bug = _tracking_bug_node->getDoubleValue();
double true_bug_error = tracking_bug - track1_deg;
double magnetic_bug_error = tracking_bug - mag_track_bearing;
// Get the errors into the (-180,180) range.
while (true_bug_error < -180.0)
true_bug_error += 360.0;
while (true_bug_error > 180.0)
true_bug_error -= 360.0;
while (magnetic_bug_error < -180.0)
magnetic_bug_error += 360.0;
while (magnetic_bug_error > 180.0)
magnetic_bug_error -= 360.0;
_true_bug_error_node->setDoubleValue(true_bug_error);
_magnetic_bug_error_node->setDoubleValue(magnetic_bug_error);
} else {
_true_track_node->setDoubleValue(0.0);
_magnetic_track_node->setDoubleValue(0.0);
@ -314,4 +333,17 @@ GPS::update (double delta_time_sec)
_last_altitude_m = altitude_m;
}
double GPS::deg360 (double deg)
{
while (deg <= 0.0) {
deg += 360.0; }
while (deg > 360.0) {
deg -= 360.0; }
return deg;
}
// end of gps.cxx

17
src/Instrumentation/gps.hxx
View file

@ -31,9 +31,10 @@
* /instrumentation/gps/wp-latitude-deg
* /instrumentation/gps/wp-ID
* /instrumentation/gps/wp-name
* /instrumentation/gps/course-deg
* /instrumentation/gps/desired-course-deg
* /instrumentation/gps/get-nearest-airport
* /instrumentation/gps/waypoint-type
* /instrumentation/gps/tracking-bug
*
* Output properties:
*
@ -44,15 +45,17 @@
* /instrumentation/gps/indicated-track-magnetic-deg
* /instrumentation/gps/indicated-ground-speed-kt
*
* /instrumentation/gps/wp-distance-m
* /instrumentation/gps/wp-distance-nm
* /instrumentation/gps/wp-bearing-deg
* /instrumentation/gps/wp-bearing-mag-deg
* /instrumentation/gps/TTW
* /instrumentation/gps/radials/actual-deg
* /instrumentation/gps/course-deviation-deg
* /instrumentation/gps/course-error-nm
* /instrumentation/gps/to-flag
* /instrumentation/gps/odometer
* /instrumentation/gps/trip-odometer
* /instrumentation/gps/true-bug-error-deg
* /instrumentation/gps/magnetic-bug-error-deg
*/
class GPS : public SGSubsystem
{
@ -70,6 +73,10 @@ private:
void search (double frequency, double longitude_rad,
double latitude_rad, double altitude_m);
double deg360 (double deg);
double deg180 (double deg);
double deg90 (double deg);
SGPropertyNode_ptr _longitude_node;
SGPropertyNode_ptr _latitude_node;
SGPropertyNode_ptr _altitude_node;
@ -83,6 +90,7 @@ private:
SGPropertyNode_ptr _wp_course_node;
SGPropertyNode_ptr _get_nearest_airport_node;
SGPropertyNode_ptr _waypoint_type_node;
SGPropertyNode_ptr _tracking_bug_node;
SGPropertyNode_ptr _raim_node;
SGPropertyNode_ptr _indicated_longitude_node;
@ -94,11 +102,14 @@ private:
SGPropertyNode_ptr _wp_distance_node;
SGPropertyNode_ptr _wp_ttw_node;
SGPropertyNode_ptr _wp_bearing_node;
SGPropertyNode_ptr _wp_mag_bearing_node;
SGPropertyNode_ptr _wp_course_deviation_node;
SGPropertyNode_ptr _wp_course_error_nm_node;
SGPropertyNode_ptr _wp_to_flag_node;
SGPropertyNode_ptr _odometer_node;
SGPropertyNode_ptr _trip_odometer_node;
SGPropertyNode_ptr _true_bug_error_node;
SGPropertyNode_ptr _magnetic_bug_error_node;
bool _last_valid;
double _last_longitude_deg;